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  Subjects -> ENGINEERING (Total: 2118 journals)
    - CHEMICAL ENGINEERING (179 journals)
    - CIVIL ENGINEERING (159 journals)
    - ELECTRICAL ENGINEERING (89 journals)
    - ENGINEERING (1163 journals)
    - ENGINEERING MECHANICS AND MATERIALS (341 journals)
    - HYDRAULIC ENGINEERING (54 journals)
    - INDUSTRIAL ENGINEERING (54 journals)
    - MECHANICAL ENGINEERING (79 journals)

ENGINEERING (1163 journals)            First | 4 5 6 7 8 9 10 11 | Last

Journal of Inverse and Ill-posed Problems     Full-text available via subscription   (Followers: 1)
Journal of Irrigation and Drainage Engineering     Full-text available via subscription   (Followers: 13)
Journal of K-Theory     Full-text available via subscription   (Followers: 1)
Journal of King Saud University - Engineering Sciences     Open Access  
Journal of Konbin     Open Access  
Journal of Liquid Chromatography & Related Technologies     Hybrid Journal   (Followers: 9)
Journal of Management in Engineering     Full-text available via subscription   (Followers: 10)
Journal of Manufacturing Science and Engineering     Full-text available via subscription   (Followers: 11)
Journal of Manufacturing Systems     Full-text available via subscription   (Followers: 6)
Journal of Manufacturing Technology Management     Hybrid Journal   (Followers: 4)
Journal of Mathematical Modelling and Algorithms     Hybrid Journal   (Followers: 2)
Journal of Mechatronics     Full-text available via subscription  
Journal of Membrane and Separation Technology     Hybrid Journal  
Journal of Metallurgy     Open Access   (Followers: 2)
Journal of Middle European Construction and Design of Cars     Open Access   (Followers: 1)
Journal of Molecular Catalysis B: Enzymatic     Hybrid Journal   (Followers: 1)
Journal of Motor Behavior     Hybrid Journal   (Followers: 8)
Journal of Multivariate Analysis     Hybrid Journal   (Followers: 6)
Journal of Nanoengineering and Nanomanufacturing     Full-text available via subscription   (Followers: 1)
Journal of Nanoparticle Research     Hybrid Journal   (Followers: 3)
Journal of Nanoscience     Open Access  
Journal of Nanoscience and Nanotechnology     Full-text available via subscription   (Followers: 12)
Journal of NanoScience, NanoEngineering & Applications     Full-text available via subscription  
Journal of Nanotechnology     Open Access   (Followers: 2)
Journal of Nanotechnology in Engineering and Medicine     Full-text available via subscription   (Followers: 6)
Journal of Natural Gas Science and Engineering     Hybrid Journal   (Followers: 3)
Journal of Near Infrared Spectroscopy     Full-text available via subscription   (Followers: 7)
Journal of Networks     Open Access   (Followers: 4)
Journal of Nonlinear Dynamics     Open Access  
Journal of Ocean Engineering and Marine Energy     Hybrid Journal  
Journal of Oceanography and Marine Science     Open Access   (Followers: 2)
Journal of Operations Management     Hybrid Journal   (Followers: 19)
Journal of Optics     Hybrid Journal   (Followers: 2)
Journal of Optimization     Open Access  
Journal of Optoelectronics Engineering     Open Access  
Journal of Organizational Behavior     Hybrid Journal   (Followers: 31)
Journal of Petroleum Science Research     Open Access   (Followers: 1)
Journal of Phase Equilibria and Diffusion     Hybrid Journal   (Followers: 5)
Journal of Power Sources     Partially Free   (Followers: 29)
Journal of Pre-College Engineering Education Research     Open Access  
Journal of Pressure Vessel Technology     Full-text available via subscription   (Followers: 11)
Journal of Professional Issues in Engineering Education and Practice     Full-text available via subscription   (Followers: 6)
Journal of Quality and Reliability Engineering     Open Access   (Followers: 1)
Journal of Quality in Maintenance Engineering     Hybrid Journal   (Followers: 4)
Journal of Radiation Research and Applied Sciences     Open Access   (Followers: 1)
Journal of Rare Earths     Full-text available via subscription   (Followers: 2)
Journal of Real-Time Image Processing     Hybrid Journal   (Followers: 7)
Journal of Regional Science     Hybrid Journal   (Followers: 10)
Journal of Reinforced Plastics and Composites     Hybrid Journal   (Followers: 5)
Journal of Research of NIST     Open Access   (Followers: 1)
Journal of Research Updates in Polymer Science     Hybrid Journal  
Journal of Rock Mechanics and Geotechnical Engineering     Open Access   (Followers: 2)
Journal of Russian Laser Research     Hybrid Journal  
Journal of Safety Engineering     Open Access   (Followers: 5)
Journal of Safety Research     Hybrid Journal   (Followers: 18)
Journal of Science and Technology     Open Access  
Journal of Science and Technology (Ghana)     Open Access   (Followers: 2)
Journal of Science and Technology Policy Management     Hybrid Journal   (Followers: 2)
Journal of Scientific Computing     Hybrid Journal   (Followers: 3)
Journal of Scientific Innovations for Development     Open Access   (Followers: 2)
Journal of Semiconductors     Full-text available via subscription   (Followers: 2)
Journal of Sensor Technology     Open Access   (Followers: 3)
Journal of Shanghai Jiaotong University (Science)     Hybrid Journal  
Journal of Sol-Gel Science and Technology     Hybrid Journal   (Followers: 2)
Journal of Solar Energy     Open Access   (Followers: 5)
Journal of Solar Energy Engineering     Full-text available via subscription   (Followers: 16)
Journal of Superconductivity and Novel Magnetism     Partially Free   (Followers: 1)
Journal of Surface Investigation. X-ray, Synchrotron and Neutron Techniques     Hybrid Journal   (Followers: 1)
Journal of Surveying Engineering     Full-text available via subscription   (Followers: 7)
Journal of Technology Management & Innovation     Open Access   (Followers: 3)
Journal of Telecommunications Management     Full-text available via subscription   (Followers: 3)
Journal of Testing and Evaluation     Full-text available via subscription   (Followers: 11)
Journal of the Air & Waste Management Association     Hybrid Journal   (Followers: 3)
Journal of the Chinese Institute of Engineers     Hybrid Journal  
Journal of the Chinese Institute of Industrial Engineers     Hybrid Journal   (Followers: 1)
Journal of the Franklin Institute     Full-text available via subscription   (Followers: 2)
Journal of the Institution of Engineers (India ): Series D     Hybrid Journal  
Journal of the Institution of Engineers (India) : Series B     Hybrid Journal   (Followers: 1)
Journal of The Institution of Engineers (India) : Series E     Hybrid Journal   (Followers: 1)
Journal of the Institution of Engineers (India): Series A     Hybrid Journal  
Journal of the Institution of Engineers (India): Series C     Hybrid Journal   (Followers: 1)
Journal of the National Science Foundation of Sri Lanka     Open Access   (Followers: 1)
Journal of the University of Ruhuna     Open Access  
Journal of Thermal Science and Engineering Applications     Full-text available via subscription   (Followers: 3)
Journal of Thermal Stresses     Hybrid Journal   (Followers: 3)
Journal of Transplantation     Open Access   (Followers: 3)
Journal of Transport and Supply Chain Management     Open Access   (Followers: 6)
Journal of Transportation Engineering     Full-text available via subscription   (Followers: 14)
Journal of Transportation Systems Engineering and Information Technology     Full-text available via subscription   (Followers: 14)
Journal of Tribology     Full-text available via subscription   (Followers: 27)
Journal of Turbomachinery     Full-text available via subscription   (Followers: 9)
Journal of Turbulence     Hybrid Journal  
Journal of Unmanned Vehicle Systems     Full-text available via subscription   (Followers: 2)
Journal of Urban and Environmental Engineering     Open Access  
Journal of Urban Planning and Development     Full-text available via subscription   (Followers: 32)
Journal of Urban Regeneration & Renewal     Full-text available via subscription   (Followers: 17)
Journal of Vibration and Acoustics     Full-text available via subscription   (Followers: 27)
Journal of Visualization     Hybrid Journal   (Followers: 2)
Journal of Volcanology and Seismology     Hybrid Journal   (Followers: 3)
Journal of Wuhan University of Technology-Mater. Sci. Ed.     Hybrid Journal  

  First | 4 5 6 7 8 9 10 11 | Last

Journal Cover   Pest Management Science
  [SJR: 1.262]   [H-I: 72]   [7 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1526-498X - ISSN (Online) 1526-4998
   Published by John Wiley and Sons Homepage  [1607 journals]
  • VKOR‐variant and sex are the main influencing factors on
           bromadiolone tolerance of house mouse (Mus musculus L.)
    • Authors: Tanja Šćepović; Goran Jokić, Alexandra Esther, Dragan Kataranovski, Petar Vukša, Suzana Đedović, Marina Vukša
      Abstract: Background After reports of management problems in practice, a survey was conducted to determine the presence of bromadiolone resistant animals in different house mouse (Mus musculus L.) populations in Serbia. A 21‐day no‐choice feeding test was carried out to examine the resistance of house mice to bromadiolone. Eighty house mice collected from 4 locations (10 males and 10 females per location) were tested for bromadiolone tolerance. Surviving animals and their F1 offspring were screened for mutations. The influence of VKOR‐variant, zygosity and sex on bromadiolone tolerance were analysed. Results Bait intake and changes in body weight revealed different animal responses regarding susceptibility or resistance. Leu128Ser, Tyr139Cys and a new Ala21Thr polymorphism were detected in wild‐born survivors and their F1 generation. However, not every individual with the polymorphism Leu128Ser and Tyr139Cys survived the feeding test. VKOR‐variants and sex caused variations in bromadiolone tolerance. Conclusion For the first time it was shown that the VKOR‐variant, along with sex, is responsible for bromadiolone tolerance in house mice. Other factors, including sex specific ones, influencing bromadiolone tolerance cannot be excluded. The tolerance levels of VKOR variants should be determined in further studies in order to evaluate the effectivness of bromadiolone in sustainable management.
      PubDate: 2015-04-22T04:12:15.996363-05:
      DOI: 10.1002/ps.4027
       
  • A pyrosequencing‐based method to quantify genetic substitutions
           associated with resistance to SDHI‐fungicides in Botrytis spp.
           populations
    • Authors: Mélanie Gobeil‐Richard; David‐Mathieu Tremblay, Carole Beaulieu, Hervé Van der Heyden, Odile Carisse
      Abstract: BACKGROUND The genetic underlying resistance mechanisms in the population of the phytopathogenic fungus Botrytis cinerea are well documented. Specifically, several genetic substitutions associated with SDHIs‐based fungicide resistance were identified in the succinate dehydrogenase gene. The objective of this work was to develop a molecular tool for accurate quantification of these genetic substitutions within Botrytis populations. A test using the PyroMark Q24 instrument was designed to detect and quantify five genetic substitutions associated with SDHIs resistance. RESULTS The technique is based on sequencing by synthesis and generated quantitative and accurate data with a limit of quantification of a minimum of 500 spores. There was a linear relationship between known and estimated percent of spore with the targeted genetic substitutions and wild‐type strains at ratios of 0%–100%, with 20% increment. CONCLUSION With the pyrosequencing assay developed in this study, a large number of Botrytis spp. individuals can be characterized in a timely fashion with greater accuracy than commonly used methods. Hence, pyrosequencing‐based methods will be useful to improve our understanding of fungicide resistance, detect arrival of new genetic substitutions, monitor shifts in fungal populations, assess the effectiveness of anti‐resistance strategies and for routine monitoring of fungicide resistance.
      PubDate: 2015-04-21T00:48:08.920301-05:
      DOI: 10.1002/ps.4026
       
  • Pesticides and reduced‐risk insecticides, native bees and
           Pantropical stingless bees: pitfalls and perspectives
    • Authors: Wagner F Barbosa; Guy Smagghe, Raul Narciso C Guedes
      Abstract: Although invertebrates generally have a low public profile, the honey bee, Apis mellifera L., is a flagship species whose popularity likely derives from the products it provides and its perceived ecological services. Therefore, the raging debate regarding honey bee decline has surpassed the realm of beekeepers, academia, industry and regulatory agencies and now also encompasses non‐governmental agencies, media, fiction writers and the general public. The early interest and concern about honey bee colony collapse disorder (CCD) soon shifted to the bigger issue of pollinator decline, with a focus on the potential involvement of pesticides in such a phenomenon. Pesticides were previously recognized as the potential culprits of the reported declines, particularly the neonicotinoid insecticides due to their widespread and peculiar use in agriculture. However, the evidence for the potential pivotal role of these neonicotinoids in the honey bee decline remains a matter of debate, with an increased recognition of the multifactorial nature of the problem and the lack of a direct association between the noted decline and neonicotinoid use. The focus on the decline of honey bee populations subsequently spread to other species, and bumble bees became another matter of concern, particularly in Europe and the US. Other bee species, ones that are particularly important in other regions of the world, remain the object of little concern (unjustifiably so). Furthermore, the continuous focus on neonicotinoids is also in need of revision, as the current evidence suggests that a broad spectrum of compounds deserve attention. Here we address both shortcomings.
      PubDate: 2015-04-17T04:32:21.341529-05:
      DOI: 10.1002/ps.4025
       
  • The degradation rate of thiamethoxam in European field studies
    • Authors: Martin J. Hilton; Tim D. Jarvis, Dean C. Ricketts
      Abstract: Background Thiamethoxam is a systemic and contact pesticidal active substance in the neonicotinoid class of insecticides, used world‐wide to control a range of insects. Recently, concerns have been expressed regarding possible effects of neonicotinoids to bees and other wildlife. The DT50 of thiamethoxam in soil may be crucial to assessing the potential long‐term exposure of non‐target organisms to thiamethoxam. There are currently no detailed publicly available data for the field soil degradation of thiamethoxam under European conditions. We publish field soil DT50 values of thiamethoxam from studies conducted in several European locations, under a range of realistic agronomic conditions. Results Field soil DT50 values normalized to 20 °C ranged between 7.1 – 92.3 days (geomean = 31.2 days; n = 18). Conclusion The degradation rate of thiamethoxam was not significantly affected by application type, cropped fields vs. bare soil, soil pH, organic matter content, or repeated annual applications. Soil photolysis and leaching were negligible; therefore calculated DT50 values were concluded to represent microbial degradation. The field degradation rates of thiamethoxam are faster than those previously reported from laboratory degradation studies. They demonstrate that thiamethoxam will degrade to concentrations
      PubDate: 2015-04-17T04:26:03.744961-05:
      DOI: 10.1002/ps.4024
       
  • Inheritance of field‐relevant resistance to the Bacillus
           thuringiensis protein Cry1Ac in Pectinophora gossypiella (Lepidoptera:
           Gelechiidae) collected from India
    • Authors: Rupa Nair; Subray P Kamath, Komarlingam S Mohan, Graham Head, Douglas V. Sumerford
      Abstract: BACKGROUND The inheritance and phenotypic expression of resistance to Bacillus thuringiensis Cry1Ac‐insecticidal protein were studied in selected populations of pink bollworm, Pectinophora gossypiella (Saunders), that were collected from Bollgard cotton in India. The individual populations in the pool were Cry1Ac‐resistant and sourced from Cry1Ac‐containing Bt cotton (Bollgard) hybrids in 2010. RESULTS Laboratory selection on diet with 1.0 µg/ mL of Cry1Ac protein increased the percentage reaching ≥ third instars from 7% in the F3 generation to 94% in the F15 generation, a 257‐fold increase in median lethal concentration relative to the susceptible strain. The analysis of reciprocal genetic crosses between the Cry1Ac‐resistant strain NKJ and a susceptible laboratory strain MRC showed dominance (h) of 0.22 indicating that the inheritance of Cry1Ac‐resistance is partially recessive at Cry1Ac concentrations comparable to those in Bollgard. Analyses of backcrosses of F1 hybrid moths with NKJ and MRC indicated that resistance is autosomal. The Cry1Ac‐resistant strain exhibited little or no cross‐resistance to the Cry2Ab2 protein. CONCLUSION This is the first study of the dominance of Cry1Ac field‐resistance in P. gossypiella. The results provide the basis for refining resistance management strategies for Bt cotton.
      PubDate: 2015-04-13T01:57:18.94754-05:0
      DOI: 10.1002/ps.4023
       
  • Effect of Solution and Leaf Surface Polarity on Droplet Spread Area and
           Contact Angle
    • Authors: Justin J Nairn; W Alison Forster, Rebecca M van Leeuwen
      Abstract: BACKGROUND How much an agrochemical spray droplet spreads on a leaf surface can significantly influence efficacy. This study investigates the effect solution polarity has on droplet spreading on leaf surfaces and whether the relative leaf surface polarity, as quantified using the wetting tension dielectric (WTD) technique, influences the final spread area. Contact angles and spread areas were measured using four probe solutions on 17 species. RESULTS Probe solution polarity was found to affect the measured spread area and the contact angle of the droplets on non hairy leaves. Leaf hairs skewed the spread area measurement preventing investigation of the influence of surface polarity on hairy leaves. WTD measured leaf surface polarity of non‐hairy leaves was found to strongly correlate with the effect of solution polarity on spread area. CONCLUSIONS For non‐polar leaf surfaces the spread area decreases with increasing solution polarity, for neutral surfaces polarity has no effect on spread area, and for polar leaf surfaces the spread area increase with increasing solution polarity. These results attest to the use of the WTD technique as a means to quantify leaf surface polarity.
      PubDate: 2015-04-10T03:17:20.595564-05:
      DOI: 10.1002/ps.4022
       
  • Evidence of a target resistance to antivitamin K rodenticides in the roof
           rat Rattus rattus: Identification and characterization of a novel Y25F
           mutation in the Vkorc1 gene
    • Authors: Joffrey Goulois; Audrey Chapuzet, Véronique Lambert, Nolan Chatron, Luba Tchertanov, Lionel Legros, Etienne Benoît, Virginie Lattard
      Abstract: BACKGROUND Despite intensive use of Bromadiolone, rodent control was inefficient in a farm in Zaragoza (Spain) infested by rats. While metabolic resistance was previously described in this rodent species, the observation of a target resistance to vitamin K rodenticides had been poorly documented in Rattus rattus. RESULTS From rats trapped in the farm, cytochrome b and Vkorc1 gene were amplified by PCR and sequenced in order to identify species and detect potential Vkorc1 mutations. VKORC1 deduced amino acids sequences were thus expressed in Pichia pastoris and inhibition constants towards various rodenticides were determined. The 10 rats trapped in the farm were all identified as Rattus rattus. They were found to be homozygous for the g.74A>T nucleotide replacement in exon 1 of the Vkorc1 gene leading to p.Y25F mutation. This mutation led to increase in Ki towards various rodenticides probably caused by a partial loss of helical structure of TM4. CONCLUSION The p.Y25F mutation detected in Vkorc1 gene in Rattus rattus trapped in the Spanish farm is associated to the resistance phenotype to bromadiolone that has been observed. It is the first evidence of target resistance to AVKs in Rattus rattus.
      PubDate: 2015-04-07T02:15:35.679398-05:
      DOI: 10.1002/ps.4020
       
  • EPSPS gene amplification in glyphosate‐resistant Bromus diandrus
    • Authors: Jenna M Malone; Sarah Morran, Neil Shirley, Peter Boutsalis, Christopher Preston
      Abstract: BACKGROUND Glyphosate is the most widely used herbicide in the World and has been intensively used to control B. diandrus, a problematic weed of crops and pastures in southern Australia. RESULTS Resistance to glyphosate was identified in two populations of B. diandrus that were nearly 5‐fold more resistant to glyphosate than wild type plants. Both populations contained EPSPS gene amplification, with resistant plants having an average of around 20 fold the number of copies of EPSPS compared with susceptible plants. EPSPS expression was also increased in resistant plants of both populations; however, expression levels were not correlated with the number of EPSPS copies. Amplification of only one of the four EPSPS genes present in B. diandus was detected. Investigation into the inheritance of glyphosate resistance found no segregation in the F2 generation. Every individual in the F2 populations contained between three and 30 copies of EPSPS; however, on average they contained fewer copies compared with the parent resistant population. CONCLUSIONS Glyphosate resistance in B. diandrus is due to EPSPS gene amplification. Resistance is heritable, but complex.
      PubDate: 2015-04-06T07:55:56.031411-05:
      DOI: 10.1002/ps.4019
       
  • Design, Synthesis, Antiviral Activity and 3D‐QSAR Study of Novel
           1,4‐Pentadien‐3‐one Derivatives Containing the
           1,3,4‐Oxadiazole Moiety
    • Authors: Xiuhai Gan; Deyu Hu, Pei Li, Jian Wu, Xuewen Chen, Wei Xue, Baoan Song
      Abstract: BACKGROUND 1,4‐Pentadien‐3‐one and 1,3,4‐oxadiazole derivatives possess good antiviral activities, their substructure units are usually used in antiviral agent design. In order to discover novel molecules with high antiviral activities, a series of 1,4‐pentadien‐3‐one derivatives containing the 1,3,4‐oxadiazole moiety were designed and synthesized. RESULTS Bioassays showed that most of the title compounds exhibited good inhibitory activities against tobacco mosaic virus (TMV) in vivo. In particular, compound 8f possessed the best protective activity against TMV, with EC50 value of 135.56 mg L−1, which were superior to ribavirin (435.99 mg L−1). The comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) of 3D‐QSAR with respect to the protective activities were studied with the values of q2 and r2 for CoMFA and CoMSIA model were 0.751, 0.775 and 0.936, 0.925 respectively. Compound 8 k was designed and synthesized based on the 3D‐QSAR model, and bioassay showed better protective activity (EC50, 123.53 mg L−1) than 8 f. CONCLUSION Some of the title compounds displayed good antiviral activities. 3D‐QSAR models revealed that the appropriate compact electron‐withdrawing and hydrophobic group at the benzene ring could enhance antiviral activity. These results could provide important structural insights for the design of highly active 1,4‐pentadien‐3‐one derivatives.
      PubDate: 2015-04-06T07:54:53.847995-05:
      DOI: 10.1002/ps.4018
       
  • Dual effects of Metarhizium spp. and Clonostachys rosea against an insect
           and a seed borne pathogen in wheat
    • Authors: Chad A. Keyser; Birgit Jensen, Nicolai V. Meyling
      Abstract: BACKGROUND Crops are often prone to both insect herbivory and disease which necessitate multiple control measures. Ideally an efficacious biological control agent must adequately control the target organism and not be inhibited by other biological control agents when applied simultaneously. Wheat seeds infected with the plant pathogen Fusarium culmorum were treated with Metarhizium brunneum or M. flavoviride and Clonostachys rosea individually and in combination with the expectation to control both root‐feeding insects and the pathogen. Emerging roots were evaluated for disease and then placed with Tenebrio molitor larvae which were monitored for infection. RESULTS Plant‐disease symptoms were nearly absent for seeds treated with C. rosea, both individually and in combination with Metarhizium spp. Furthermore, roots grown from seeds treated with Metarhizium spp. caused significant levels of fungal infection in larvae when used individually or combined with C. rosea. However, co‐treated seeds showed reduced virulence towards T. molitor as compared to treatments with Metarhizium spp. only. CONCLUSIONS This study clearly shows that seed treatments with both the entomopathogenic fungus M. brunneum and the mycoparasitic fungus C. rosea can protect plant roots from insects and disease. The dual‐treatment approach to biological control presented here harmonizes well with the ideals of IPM strategies.
      PubDate: 2015-04-01T04:21:09.422338-05:
      DOI: 10.1002/ps.4015
       
  • Spray distribution evaluation of different setting of a hand‐held
           trolley sprayer used in greenhouse tomato crops
    • Authors: Jordi Llop; Emilio Gi1, Montserrat Gallart, Felipe Contador, Mireia Ercilla
      Abstract: Background Hand‐held trolley sprayers have been recently promoted to improve techniques of spray application on greenhouses in south‐eastern Spain. However, certain aspects remain to be improved. A modified hand‐held trolley sprayer was evaluated under two different canopy conditions (high and low canopy density) and with several sprayer settings (nozzle type, air assistance, and spray volume). In this study, the deposition, coverage, and uniformity of distribution of the spray on the canopy have been assessed. Results The deposition on leaves was significantly higher when flat fan nozzles and air assistance were used at both high and low spray volumes. No differences were detected between the reference system at a high spray volume and the modified trolley at a low spray volume. Flat fan nozzles with air assistance increased penetrability into the canopy. Conclusions Air assistance and flat fan nozzles allow volume rates to be reduced while maintaining or improving spray quality distribution. The working parameters of hand‐held sprayers must be considered to reduce environmental risk and increase the efficacy of the spraying process.
      PubDate: 2015-04-01T04:20:58.435208-05:
      DOI: 10.1002/ps.4014
       
  • Efficacy and Environmental Fate of Imazapyr from Directed Helicopter
           Applications Targeting Tamarix Species Infestations in Colorado, USA
    • Authors: Cameron H Douglass; Scott J Nissen, Andrew R Kniss
      Abstract: Background Aerial imazapyr applications are the most common and cost effective method for controlling invasive tamarisk, but few studies have investigated whether or how infestation and site characteristics influence control and non‐target impacts. This study used vertical stands with filter papers, plus soil and tree canopy sampling to investigate how tamarisk canopies affected retention of applied imazapyr, soil herbicide residues and tree mortality. Results Tamarisk canopies captured 71% of aerially‐applied imazapyr, resulting in significantly lower soil residues beneath the tree canopy. Although initial imazapyr soil residue levels outside the tree canopy were four times greater than those inside, soil degradation occurred 2.4x faster outside the tamarisk canopy and resulted in lower herbicide residues. Tamarisk mortality within three years was 70%, but variability in control appeared to be affected by non‐linear stand boundaries and tall site obstructions. These same factors also increased variability in the actual quantity of herbicide applied, exacerbating collateral impacts on desirable understory species. Conclusion While aerial imazapyr applications are highly effective in controlling tamarisk, our study provides evidence for the importance of evaluating overall site suitability for this management strategy so the probability of unintended ecological effects can be minimized.
      PubDate: 2015-04-01T04:20:54.867494-05:
      DOI: 10.1002/ps.4016
       
  • High resolution melt and morphological analyses of mealybugs (Hemiptera:
           Pseudococcidae) from cacao: tools for the control of Cacao Swollen Shoot
           Virus spread
    • Authors: Andy Wetten; Colin Campbell, Joël Allainguillaume
      Abstract: BACKGROUND Mealybugs (Hemiptera: Coccoidea: Pseudococcidae) are key vectors of badnaviruses, including Cacao Swollen Shoot Virus (CSSV) the most damaging virus affecting cacao (Theobroma cacao L.). The effectiveness of mealybugs as virus vectors is species dependent and it is therefore vital that CSSV resistance breeding programmes in cacao incorporate accurate mealybug identification. In this work the efficacy of a CO1‐based DNA barcoding approach to species identification was evaluated by screening a range of mealybugs collected from cacao in seven countries. RESULTS Morphologically similar adult females were characterised by scanning electron microscopy and then, following DNA extraction, were screened with CO1 barcoding markers. A high degree of CO1 sequence homology was observed for all 11 individual haplotypes including those accessions from distinct geographical regions. This has allowed for the design of a High Resolution Melt (HRM) assay capable of rapid identification of the commonly encountered mealybug pests of cacao. CONCLUSIONS HRM Analysis (HRMA) readily differentiated between mealybug pests of cacao that can not necessarily be identified by conventional morphological analysis. This new approach, therefore, has potential to facilitate breeding for resistance to CSSV and other mealybug transmitted diseases.
      PubDate: 2015-04-01T04:20:51.241202-05:
      DOI: 10.1002/ps.4017
       
  • Development of selectable marker‐free transgenic potato plants
           expressing cry3A against the Colorado potato beetle (Leptinotarsa
           decemlineata Say)
    • Authors: Wen‐chao Guo; Zhi‐an Wang, Xiao‐li Luo, Xin Jin, Jing Chang, Jiang He, Er‐xun Tu, Ying‐chuan Tian, Huai‐jun Si, Jia‐he Wu
      Abstract: BACKGROUND Elimination of selectable marker genes (SMGs) is important for the safe assessment and commercial use of transgenic plants. The destructive and invasive Colorado potato beetle (CPB) poses a serious threat to potato production. In response to this need, selectable marker‐free transgenic potato lines expressing cry3A were developed to control the damage and spread of CPB. RESULTS We simultaneously introduced cry3A and npt II genes harboured in different plasmids into the potato genome using the Agrobacterium‐mediated co‐transformation method. Four selectable marker‐free transgenic potato (CT) lines expressing cry3A were developed by self‐crossing segregation and molecular analyses, including Southern blot, Western blot and enzyme‐linked immunosorbent assay (ELISA) assays. CT lines were used in a resistance bioassay against CPB in the laboratory and field. In the laboratory, CT lines exhibited high resistance to CPB and 100% mortality of 1st instar larvae occurred 6 days after infestation. In the field, untransformed plant leaves were almost entirely consumed with an average of 155 larvae present per plant 25 days after inoculation. However, CT lines showed no damage symptoms with approximately 2.5 larvae surviving per plant. CONCLUSION We successfully eliminated the SMG from the transgenic potato lines expressing cry3A, which can decrease CPB damage, control the spread of this pest eastwards and alleviate the concern regarding the safe assessment of regulatory requirements.
      PubDate: 2015-03-26T03:17:16.826399-05:
      DOI: 10.1002/ps.4013
       
  • Lactones 47. Synthesis, antifeedant and antibacterial activity of
           γ‐lactones with p‐methoxyphenyl substituent
    • Authors: Marcelina Mazur; Andrzej Skrobiszewski, Witold Gładkowski, Magdalena Podkowik, Jacek Bania, Jan Nawrot, Tomasz Klejdysz, Czesław Wawrzeńczyk
      Abstract: BACKGROUND Lactones are well known because of their biological activity. The grosheimin and repin are potent deterrents against storage pests. The unsaturated lactones exhibited wide spectrum of antibacterial activity. In our study we focused on synthesis and evaluation of biological activity of anisaldehyde derivatives containing lactone function. RESULTS Four new lactones were synthesized in one‐step reductive dehalogenation or dehydrohalogenation reactions. These compounds together with halolactones synthesized earlier (1, 3, 7, 8) were tested for their antifeedant activity toward the Sitophilus granaries, Trogoderma granarium and Tribolium confusum. The results of the tests proved that the highest activity, comparable with azadirachtin, towards all tested pests (T in the range 143.3‐183.9) was observed for lactone with vinyl substituent (6). Antibacterial activity of those compounds was also evaluated. The most potent lactone (2) was active towards Gram‐positive bacteria strains. CONCLUSIONS The results of biological tests proved that removing of halogen atom significantly increased the antifeedant properties of γ‐lactones with p‐methoxyphenyl substituent. The unsaturated lactones 5, 6 are the most promising ones in the context of possible industrial application of these compounds as the crops protecting agents. Further structural modifications of lactones with aromatic ring are needed to find important structural factors increasing the antibacterial activity.
      PubDate: 2015-03-25T01:27:38.130576-05:
      DOI: 10.1002/ps.4012
       
  • Insecticide resistance alleles in wetland and residential populations of
           the West Nile virus vector Culex pipiens in New Jersey, USA
    • Authors: Brian J. Johnson; Dina M. Fonseca
      Abstract: BACKGROUND Despite the extensive use of insecticides to control Culex pipiens in the aftermath of West Nile virus, knowledge of the spatial distribution and frequency of insecticide resistance in this species is poorly understood in the United States. This paper reports on the occurrence of upregulated esterases that detoxify organophosphates (OP) and mutations conferring resistance to pyrethroid insecticides in natural and developed areas of New Jersey (USA). RESULTS We report the first observations of the OP resistance alleles, EsterB1 and Ester2, and the classical knockdown resistance (kdr) mutation, L1014F, in New Jersey Cx. pipiens. Upregulated EsterB1 peaked at 23% (Mean±SE=12 ± 2.3%) and Ester2 at 14% (8 ± 1.8%) and both were widely distributed. L1014F, which confers strong resistance to pyrethroids when homozygous, was also widely distributed and ranged in frequency from 2‐19% (5.1% heterozygous individuals and 1.4% homozygous). CONCLUSION We demonstrate that OP resistance is common and broadly distributed in New Jersey Cx. pipiens and that homozygous individuals resistant to pyrethroids are present. Further, we detected double mutants at Ester and kdr, a condition that may annul the purging effects of insecticide rotations. Our results therefore indicate the need for continued monitoring of insecticide resistance in order to achieve effective mosquito control.
      PubDate: 2015-03-25T01:27:26.998089-05:
      DOI: 10.1002/ps.4011
       
  • Design, Synthesis, Antiviral Activity and Mode of Action of
           Phenanthrene–Containing N‐Heterocyclic Compounds Inspired from
           Phenanthroindolizidine Alkaloid Antofine
    • Authors: Xiuling Yu; Peng Wei, Ziwen Wang, Yuxiu Liu, Lizhong Wang, Qingmin Wang
      Abstract: BACKGROUND Phenanthroindolizidine alkaloid antofine and its analogues have excellent antiviral activity against tobacco mosaic virus (TMV). To simplify the structure and the synthesis hardness of phenanthroindolizidine alkaloid, a series of phenanthrene–containing N‐heterocyclic compounds 1–33 were designed and synthesized based on the intermolecular interaction of antofine and TMV RNA and systematically evaluated for their anti‐TMV activity. RESULT Most of these compounds exhibited good to reasonable anti‐TMV activity. The optimum compounds 5, 12 and 21 displayed higher activity than the lead compound antofine and commercial ribavirin. Compound 12 was chosen for the field trials of antiviral efficacy against TMV, and found to exhibit better activity than control plant virus inhibitors. Compounds 5 and 12 were chosen for mode of action studies. The changes of fluorescence intensity of 5 and 12 on separated TMV RNA showed that these small molecules can also bind to TMV RNA, but the mode is much different from that of antofine. CONCLUSION The compounds combining phenanthrene and N‐heterocyclic ring could maintain the anti‐TMV activity of phenanthroindolizidines, but their modes of action are different from that of antofine. Present study lays a good foundation for us to find more efficient anti‐plant virus reagents.
      PubDate: 2015-03-24T03:39:23.252475-05:
      DOI: 10.1002/ps.4008
       
  • Managing the evolution of herbicide resistance
    • Authors: Jeffrey A. Evans; Patrick J. Tranel, Aaron G. Hager, Brian Schutte, Chenxi Wu, Laura A. Chatham, Adam S. Davis
      Abstract: BACKGROUND Understanding and managing the evolutionary responses of pests and pathogens to control efforts is essential to human health and survival. Herbicide‐resistant (HR) weeds undermine agricultural sustainability, productivity, and profitability, yet the epidemiology of resistance evolution – particularly at landscape scales – is poorly understood. We studied glyphosate‐resistance (GR) in a major agricultural weed, Amaranthus tuberculatus (common waterhemp) using landscape, weed, and management data from 105 central Illinois grain farms, including over 500 site‐years of herbicide application records. RESULTS GR A. tuberculatus occurrence was greatest in fields with frequent glyphosate applications, high annual rates of herbicide mechanisms of action (MOA) turnover, and few MOAs field−1 year−1. Combining herbicide MOAs at the time of application by herbicide mixing reduced the likelihood of GR A. tuberculatus. CONCLUSIONS These findings illustrate the importance of examining large scale evolutionary processes at relevant spatial scales. Although measures such as herbicide mixing may delay GR or other HR weed traits, they are unlikely to prevent them. Long‐term weed management will require truly diversified management practices that that minimize selection for HR traits.
      PubDate: 2015-03-24T03:35:34.304571-05:
      DOI: 10.1002/ps.4009
       
  • Comparative and synergistic activity of Rosmarinus officinalis L.
           essential oil constituents against the larvae and an ovarian cell line of
           the cabbage looper, Trichoplusia ni (Lep., Noctuidae)
    • Authors: Jun‐Hyung Tak; Eduardo Jovel, Murray B. Isman
      Abstract: BACKGROUND Plant essential oils are usually complex mixtures, and many factors can affect their chemical composition. To identify relationships between composition and bioactivity of the constituents, comparative and synergistic interactions of the major constituents of rosemary essential oil were evaluated against third instar larvae and an ovarian cell line of the cabbage looper, Trichoplusia ni via different methods of application. RESULTS The major constituents of the rosemary oil we used were 1,8‐cineole, (±)‐camphor, (+)‐α‐pinene and camphene. Via topical application to larvae, 1,8‐cineole was identified as the major active compound, whereas via fumigation, 1,8‐cineole and (±)‐camphor, and in a cytotoxicity assay, (+)‐α‐pinene, were determined to be the major active principles. Several combinations of these constituents exhibited synergistic insecticidal activities when topically applied, particularly among combinations of three major constituents, (±)‐camphor, (+)‐α‐pinene, and camphene. A binary mixture of 1,8‐cineole and (±)‐camphor showed enhanced activity, with a synergy ratio of 1.72. CONCLUSION Based on our results, the insecticidal activity of rosemary oil appears to be a consequence of the synergistic interaction between 1,8‐cineole and (±)‐camphor, and (±)‐camphor should be considered a promising synergizing agent.
      PubDate: 2015-03-24T03:35:18.008443-05:
      DOI: 10.1002/ps.4010
       
  • Development of a regulatory testing procedure to study the metabolism of
           pesticides in farmed fish
    • Authors: Christian Schlechtriem; Ina Goeritz, Cornelia Atorf, Elena Bergendahl, Paul Seymour, Paul Whalley
      Abstract: Background Diets used in commercial fish farming use significant proportions of crop derived commodities and it is important to understand the potential for transfer of any pesticide residues on the crop into edible tissues in fish. It is a current requirement in the EU that fish metabolism studies must be performed when a pesticide is used in crops where commodities or processed fractions are fed to farmed fish. Fish metabolism studies in both rainbow trout and common carp have been carried out, following the new working document on nature of pesticed residues in fish using 14C labelled pesticide. Results The ingestion of the experimental diets by rainbow trout and common carp resulted in the uptake and metabolism of the test item as shown by liquid scintillation counting (LSC) analysis in combination with radio‐TLC analysis. Species specific differences in the chromatographic profile of pesticide metabolites were observed regarding the proportional distribution of metabolites rather than their general pattern. Conclusions Metabolism studies for regulatory purposes can be carried out with both fish species under laboratory conditions. The experimental design reported is suitable to quantify the transfer of residues to edible tissues and to enable characterisation of the chemical nature of residues.
      PubDate: 2015-03-20T05:52:24.481287-05:
      DOI: 10.1002/ps.4007
       
  • Broad resistance to AHAS‐inhibiting herbicides in feral radish
           (Raphanus sativus L.) populations from Argentina
    • Authors: Claudio E Pandolfo; Alejandro Presotto, Florencia Moreno, Ida Dossou, Juan P Migasso, Ernesto Sakima, Miguel Cantamutto
      Abstract: BACKGROUND Soon after the commercial release of sunflower cultivars resistant to imidazolinone herbicides (IMI), several uncontrolled feral radish (Raphanus sativus L.) populations were found in southeastern Buenos Aires, Argentina. These populations were studied in field, glasshouse and laboratory experiments aiming to characterize their resistant profile and to develop management tools. RESULTS Three feral radish accessions were highly resistant to ten active ingredients of five families of acetohydroxyacid synthase (AHAS) inhibiting herbicides. Sequence analysis of the AHAS gene detected a Trp574Leu mutation in all resistant accessions. One accession with an intermediate level of resistance was heterozygous for this mutation, probably due to gene exchange with a susceptible sub‐population located in the field margin. Herbicide resistant and susceptible radish could be controlled in sunflower by alternative herbicides. CONCLUSION This is the first report of feral radish with resistance to herbicides belonging to all the AHAS‐inhibiting herbicide families, conferred by Trp574Leu mutation in the AHAS gene. An appropriate herbicide rotation with alternative herbicides such as fluorochloridone or aclonifen, and an increase in the diversity of cropping systems is important to minimize the prevalence of these biotypes.
      PubDate: 2015-03-19T12:17:59.964993-05:
      DOI: 10.1002/ps.4006
       
  • Glyphosate resistance in Echinochloa colona: phenotypic characterization
           and quantification of selection intensity
    • Authors: Goh Sou Sheng; Martin M Vila‐Aiub, Roberto Busi, Stephen B Powles
      Abstract: BACKGROUND A population of Echinochloa colona infesting agricultural fields in the northern region of Western Australia evolved glyphosate resistance after 10 years of glyphosate selection. This study identified two phenotypic (susceptibility ‘S’ vs resistance ‘R’) lines from within a segregating glyphosate‐resistant population. Estimation of survival, growth and reproductive rates of the phenotypes in response to glyphosate selection helped characterize the level of resistance, fitness and the selection intensity for glyphosate in this species. RESULTS Estimations of LD50 (lethal dose) and GR50 (growth rate) have shown a 8‐fold glyphosate resistance in this population. The resistant index based on the estimation of seed number (SYn50) shows a 13‐fold resistance. As a result of linear combination of plant survival and fecundity rates, plant fitness of 0.2 and 0.8 was estimated for the S and R phenotypes when exposed to the low dose of 270 g glyphosate ha−1. At the recommended dose of 540 g glyphosate ha−1 fitness significantly decreased 5‐fold in S plants but remained markedly similar (0.7) in plants of the R phenotype. Thus, the calculated selection intensity (SI) at 540 g glyphosate ha−1 was much greater (SI = 17) than at 270 g glyphosate ha−1 (SI = 4). CONCLUSIONS The assessment of plant survival and fecundity in response to glyphosate selection in the S and R phenotypes allowed a greater accuracy in the estimation of population fitness of both phenotypes and thus the glyphosate selection intensity in E. colona. The estimation of seed number or mass of phenotypes under herbicide selection is a true ecological measure of resistance with implications for herbicide resistance evolution.
      PubDate: 2015-03-17T01:46:15.500606-05:
      DOI: 10.1002/ps.4005
       
  • Effects of CO2 dissolution on phase distribution and degradation of
           dimethyl disulfide (DMDS) in soils under grape production
    • Authors: Jeremy L. Conkle; J. Alfonso Cabrera, John Thomas, Dong Wang, Jay Gan
      Abstract: Background Dimethyl disulfide (DMDS) is a fumigant recently registered in parts of U.S. The fumigant has high pesticidal activity, but does not disperse in soils as well as other fumigants. This study assessed the use of CO2 as a propellant to improve soil dispersion and diffusion by evaluating the partitioning and degradation of DMDS after carbonation in four vineyard soils collected in California. Results The soil with the highest organic carbon content (Clarksburg) had highest soil‐water partition coefficient (Kd) (p 
      PubDate: 2015-03-13T02:16:21.251902-05:
      DOI: 10.1002/ps.4004
       
  • Using satellite multispectral imagery for damage mapping of armyworm
           (Spodoptera frugiperda) in maize at a regional scale
    • Authors: Jingcheng Zhang; Yanbo Huang, Lin Yuan, Guijun Yang, Liping Chen, Chunjiang Zhao
      Abstract: BACKGROUND Armyworm, as a destructive insect for maize, causes wide range of damage to both China and U.S. in recent years. To obtain the spatial distribution of damage area and access the damage severity, a fast and accurate loss assessment method is of great importance for effective administration. The objective of this study was to determine suitable spectral features for armyworm detecting and to develop a mapping method at regional scale based on satellite remote sensing image data. RESULTS The armyworm infestation could cause significant change in plant's leaf area index, which serves as a basis of infestation monitoring. Within a number of vegetation indices (VIs) that were examined for their sensitivity to the insect damage, the Modified Soil‐Adjusted Vegetation Index (MSAVI) was identified as the optimal VI for detecting armyworm. The univariate model that relies on two‐date satellite images significantly outperformed the multivariate model, with the overall accuracy increased from 0.50 to 0.79. CONCLUSION A mapping method for monitoring the armyworm infestation at a regional scale was developed based on univariate model and two‐date multispectral satellite images. The successful application of this method in a typical armyworm outbreak event in Tangshan, Hebei Province, China demonstrated the feasibility of the method and showed its promising potential to be implemented in practice.
      PubDate: 2015-03-11T10:28:04.512979-05:
      DOI: 10.1002/ps.4003
       
  • Supplemental food for Amblyseius swirskii in the control of thrips:
           feeding friend or foe?
    • Authors: Dominiek Vangansbeke; Duc Tung Nguyen, Joachim Audenaert, Ruth Verhoeven, Bruno Gobin, Luc Tirry, Patrick De Clercq
      Abstract: Background In IPM systems in greenhouse crops, the predatory mite Amblyseius swirskii is becoming increasingly important as a biological control agent of various pests, especially thrips and whiteflies. An emerging strategy to promote the predator's establishment and retention in the crop consists of providing food supplements. However, when faced with omnivorous pests, such as the western flower thrips, Frankliniella occidentalis, food supplements need to be applied with extreme care, in order not to boost population growth of the pest. This laboratory study was conducted to evaluate the impact of commercial products of Typha angustifolia pollen and decapsulated brine shrimp cysts (Artemia sp.) on populations of both pest and predator and on predator–prey interactions. Results Pollen was highly supportive for both F. occidentalis and A. swirskii, whereas Artemia cysts supported thrips populations to a lesser extent than those of the predator. Furthermore, a less pronounced reduction in thrips consumption by A. swirskii was observed in the presence of Artemia cysts as compared with T. angustifolia pollen. Conclusion Artemia might be a valuable alternative to pollen for supporting populations of A. swirskii in order to improve thrips management, as they are less beneficial for the pest but do support population growth of A. swirskii.
      PubDate: 2015-03-05T06:22:21.732527-05:
      DOI: 10.1002/ps.4000
       
  • Nematicidal activity of allyl bromide and dibromo(nitro)methane under
           laboratory conditions
    • Authors: Yuji Oka; Shimshon Shuker, Nadia Tkachi
      Abstract: BACKGROUND Restrictions on soil fumigants are prompting the development of new compounds for controlling nematodes, other soilborne pathogens and weeds. We evaluated nematicidal activity of five bromine compounds against Meloidogyne javanica in vitro, and tested the two most effective ones against Pratylenchus penetrans and Xiphinema index in vitro and in soil. RESULTS Only allyl bromide and dibromo(nitro)methane showed nematicidal activity against M. javanica juveniles in vitro at
      PubDate: 2015-03-05T06:22:06.705865-05:
      DOI: 10.1002/ps.4001
       
  • Evaluation of entomopathogenic nematodes and the supernatants of the
           in‐vitro culture medium of their mutualistic bacteria for the
           control of the root‐knot nematodes Meloidogyne incognita and M.
           arenaria
    • Authors: Ilker Kepenekci; Selcuk Hazir, Edwin E. Lewis
      Abstract: BACKGROUND The suppressive effect of various formulations of four entomopathogenic nematode (EPN) species and the supernatants of their symbiotic bacteria on the root‐knot nematodes (RKN), Meloidogyne incognita and M. arenaria in tomato roots were evaluated. The EPNs Steinernema carpocapsae, S. feltiae, S. glaseri and Heterorhabditis bacteriophora were applied as either live infective juveniles (IJs) or infected insect cadavers. Spent medium from culturing the bacterial symbionts Xenorhabdus bovienii and Photorhabdus luminescens kayaii with the cells removed was also applied without their nematode partners. RESULTS The aqueous suspensions of IJs, infected cadaver applications of EPNs, and especially treatments of X. bovienii supernatant suppressed the negative impact of RKN on tomatoes. Specific responses to treatment were reduced RKN egg masses, increased plant height, and increased fresh and dry weights compared with the control where only RKNs were applied. CONCLUSION Among the treatments tested, the plant‐dipping method of X. bovienii into bacterial culture fluid may be the most practical and effective method for M. incognita and M. arenaria control.
      PubDate: 2015-02-27T01:51:58.912456-05:
      DOI: 10.1002/ps.3998
       
  • Transgenic cabbage plants with a synthetic cry1Ia8 gene from Bacillus
           thuringiensis were highly resistant against two Lepidopteran species under
           field conditions
    • Authors: Dengxia Yi; Weijie Yang, Jun Tang, Li Wang, Zhiyuan Fang, Yumei Liu, Mu Zhuang, Yangyong Zhang, Limei Yang
      Abstract: Background Plutella xylostella (Linnaeus) has become the most destructive pests in cabbage throughout the world. Cry1Ia8 cabbage has been developed to reduce the pests attacks. To better understand the efficacy of Cry1Ia8 cabbage, a homozygous Cry1Ia8 cabbage line A14‐5 was produced, and its resistance to P. xylostella, Pieris rapae (Linnaeus), and other lepidopteran pests was evaluated in the field in 2011, 2012, and 2013. Results Under natural infestation conditions, the homozygous transgenic line was highly resistant against the P. xylostella and P. rapae as compared to the untransformed control and susceptible to Mamestra brassicae (Linnaeus) and Spodoptera exigua (Hübner). The homozygous transgenic plants showed slight symptoms of damaged leaves by lepidopteran species, while the untransformed plants exhibited serious damage symptoms throughout the entire cabbage growing season. Conclusion Compared with the control, the homozygous transgenic cabbage line showed great potential for protecting cabbage from attack by P. xylostella and P. rapae in the field.
      PubDate: 2015-02-27T00:29:02.885298-05:
      DOI: 10.1002/ps.3994
       
  • Basic Substances: an opportunity for approval of low concern substances
           under EU pesticide regulation
    • Authors: Patrice A. Marchand
      Abstract: Background Plant extracts and by‐products furnish various alternative products for crop protection and are traditionally used by farmers. But the cost and timeframe for their registration as active substances are prohibitive for small companies and farmers’ associations with the new Plant Protection Products (PPP) Regulation (EC) No 1107/2009. However, there is now a possibility to register light compounds as “Basic Substances”, a new category described in article 23 and in the “whereas/ recital (18)”. Results We developed a regulatory expertise on the approval of such products in the framework of the PPP regulation. A Draft Assessment Report in one volume was established, later transformed by EC Directorate into a Basic Substance Application Template, and subsequently used by the EC as a matrix for the corresponding Guidelines for applicants (SANCO 10363/2012 rev. 9). Here we provide further tools, consisting in methodological, linguistic and strategic recommendations in order to constitute a Basic Substance Application (BSA) and proceed to its registration. Conclusion While the use of alternative agents for crop protection is increasing both in organic and conventional agriculture, these usages are still considered as “minor uses”. Our approach and tools are valuable to non‐PPP specialized applicants for simplifying and facilitating their submission of the BSA.
      PubDate: 2015-02-26T02:27:53.033168-05:
      DOI: 10.1002/ps.3997
       
  • Potential and actual uses of zeolites in crop protection
    • Authors: Caroline De Smedt; Edward Someus, Pieter Spanoghe
      Abstract: In this review, it is illustrated that zeolites have a potential to be used as crop protection agents. Similar to kaolin, zeolites can be applied as particle films against pests and diseases. Their honeycomb framework, together with their carbon dioxide sorption capacity and their heat stress reduction capacity, make them suitable as a leaf coating product. Furthermore, their water sorption capacity and their smaller particle sizes make them effective against fungal diseases and insect pests. Finally, these properties also ensure that zeolites can act as carriers of different active substances, which makes it possible to use zeolites for slow‐release applications. Based on literature, a general overview is provided of the different basic properties of zeolites as promising products in crop protection.
      PubDate: 2015-02-26T02:27:18.68575-05:0
      DOI: 10.1002/ps.3999
       
  • Increased frequency and changed methods in the treatment of sea lice
           (Lepeophtherius salmonis) in Scottish salmon farms 2005‐2011
    • Authors: Alexander G Murray
      Abstract: BACKGROUND Sea lice are the most economically and environmentally serious ectoparasite of marine salmonids. Sea lice have been largely controlled by treating with a variety of medicines. In order to understand sustainability of medicine usage an analysis of sea lice treatment data has been carried out for all Scottish salmon farms from 2005 to 2011. RESULTS Overall, there was an increase from 0.156 to 0.282 treatments month‐1; treatments could involve one or multiple agents. This increase was mostly in bath treatments (cypermethrin in 2007 largely replaced by deltamethrin and azamethiphos in 2008). Treatments using in‐feed treatments (emamectin benzoate and teflubenzuron) increased only slowly. Treatments involving more than one medicine in a single month also increased, as did the probability of follow‐up treatments. Treatments were seasonal with peaks of in‐feed treatments in March and August and bath treatments more frequent between August and December. CONCLUSION Frequency of sea lice treatment increased substantially, with an increase in multi‐agent and follow‐up treatments. This increase in treatment activity is expensive to industry and increases exposure of the neighbouring environment. This indicates earlier lice control practices were not sustainable.
      PubDate: 2015-02-24T03:16:59.167878-05:
      DOI: 10.1002/ps.3996
       
  • Widespread occurrence of both metabolic and target‐site herbicide
           resistance mechanisms in Lolium rigidum populations
    • Authors: Heping Han; Qin Yu, Mechelle J Owen, Gregory R Cawthray, Stephen B Powles
      Abstract: Background Lolium rigidum populations in Australia and globally have demonstrated rapid and widespread evolution of resistance to acetyl coenzyme A carboxylase (ACCase)‐ and acetolactate synthase (ALS)‐inhibiting herbicides. Thirty‐three resistant L. rigidum populations, randomly collected from crop fields in a most recent resistance survey, were analysed for non‐target‐site diclofop metabolism and all known target‐site ACCase gene resistance‐endowing mutations. Results The HPLC profile of [14C]‐diclofop‐methyl in vivo metabolism revealed that 79% of these resistant L. rigidum populations showed enhanced capacity for diclofop acid metabolism (metabolic resistance). ACCase gene sequencing identified that 91% of the populations contains plants with ACCase resistance mutation(s). Importantly, 70% of the populations exhibit both non‐target‐site metabolic resistance and target‐site ACCase mutations. Conclusions This work demonstrates that metabolic herbicide resistance is commonly occurring in L. rigidum and co‐evolution of both metabolic resistance and target‐site resistance is an evolutionary reality. Metabolic herbicide resistance can potentially endow resistance to many herbicides and poses a threat to herbicide sustainability and thus crop production, calling for major research and management efforts.
      PubDate: 2015-02-23T02:15:26.391989-05:
      DOI: 10.1002/ps.3995
       
  • Study on long‐distance migration of small brown planthoppers
           Laodelphax striatellus in China using next‐generation
           sequencing
    • Authors: Wenjing Zheng; Zhiqiang Li, Jiaming Zhao, Yanzhi Zhang, Changhua Wang, Xiaochun Lu, Fuyu Sun
      Abstract: Background The small brown planthopper (L. striatellus) is a wide‐spread insect pest of rice in East Asia. Previous studies have shown the long‐distance migrations undertaken by L. striatellus, but did not provide molecular evidence to support this. Results Long‐distance immigration occurred in the northeast coastal rice growing region of China. Using the SALF‐seq technique, sequence data for 2.7Gb of an abruptly increased population and 13 L. striatellus local populations from a range of regions in China that have serious rice stripe disease were obtained. A total of 2572 SNPs and 37 Indels were detected and the genotypes of many polymorphism sites were heterozygous in every sample, which indicated that there were rich genetic differences among the populations and the migration of insect pests accelerated the gene flow and increased the heterozygosity of L. striatellus populations. The genetic distance and the polymorphism markers among different populations showed that the abruptly increased population in Liaoning Province is close to several populations that from Jiangsu Province and Shandong Province. Conclusion The vector that caused rice stripe disease in the northeast of China was an immigrant population; however the population may be formed from several groups from different areas, such as Jiangsu and Shandong Provinces.
      PubDate: 2015-02-13T03:32:00.898739-05:
      DOI: 10.1002/ps.3992
       
  • Fumigation efficacy and emission reduction using low permeability film in
           orchard soil fumigation
    • Authors: Suduan Gao; Lynn M Sosnoskie, J Alfonso Cabrera, Ruijun Qin, Bradley D Hanson, James Gerik, Dong Wang, Greg T Browne, John E Thomas
      Abstract: Background Many orchards use fumigation to control soil borne pests prior to replanting. Controlling emissions is mandatory to reduce air pollution in California, USA. This research evaluated the effects of plastic film type [polyethylene (PE) or totally impermeable film (TIF)], application rate of Telone C35 [full (610 kg/ha), 2/3, or 1/3 rates], and carbonation at 207 kPa on fumigant transport (emission and in soil) and efficacy. Results While increasing fumigant concentrations under the tarp, TIF reduced emissions >95% (~2% and
      PubDate: 2015-02-13T03:31:59.797948-05:
      DOI: 10.1002/ps.3993
       
  • Lack of fitness costs and inheritance of resistance to Bacillus
           thuringiensis Cry1Ac toxin in a near‐isogenic strain of Plutella
           xylostella (Lepidoptera:Plutellidae)
    • Authors: Xun Zhu; Yanjv Yang, Qingjun Wu, Shaoli Wang, Wen Xie, Zhaojiang Guo, Shi Kang, Jixing Xia, Youjun Zhang
      Abstract: BACKGROUND Resistance to Bt formulations in insects may be associated with fitness costs. A lack of cost enable resistance alleles to persist, which may contribute to the rapid develop and spread of resistance in populations. RESULTS To assess the fitness costs associated with Bt Cry1Ac resistance in Plutella xylostella, life tables were constructed for near‐isogenic resistant strain (NIL‐R) and susceptible strain in this study. No fitness costs associated with Cry1Ac resistance in NIL‐R were detected based on duration of egg and larval stages, survival of eggs and larvae, adult longevity, fecundity, net reproductive rate, gross reproduction rate, finite rate of increase, or mean generation time. Based on log dose–probit lines, resistance in NIL‐R is incompletely recessive and results from a single, autosomal, recessive locus; the degree of dominance was estimated to be −0.74 and −0.71 for F1 (resistant ♀ × susceptible ♂) and F1’ (susceptible ♀ × resistant ♂) progeny, respectively. CONCLUSION Assessment of near‐isogenic Cry1Ac‐resistant and ‐susceptible strains of P. xylostella indicated that resistance is not accompanied by fitness costs and that resistance is incompletely recessive. These finding should be useful for managing the development of Bt Cry1Ac resistance.
      PubDate: 2015-02-12T03:30:33.803156-05:
      DOI: 10.1002/ps.3991
       
  • Establishment of an RTA‐Bddsx hybrid system for
           female‐specific splicing that can affect the sex ratio of Bactrocera
           dorsalis (Hendel) after embryonic injection
    • Authors: Chun‐Yen Huang; Chia Chia Huang, Shu‐Mei Dai, Cheng Chang
      Abstract: Background The oriental fruit fly, Bactrocera dorsalis (Hendel), a very destructive insect pest in many areas of Asia, including Taiwan, can cause significant damages by ovipositing in and larval feeding of many kinds of fruits. A female lethal system, combining the splicing property of doublesex (dsx) with the toxicity of ricin A chain (RTA), has been developed. In this system, a modified RTA is separated by Bddsx intron 3; the expressed RNA can only be spliced in females, with toxic effects, whereas the immature RTA in males is harmless. Results Two RTA‐Bddsx constructs, clone BE 24–7 and clone CF 26–21, containing Bddsx intron 3 and its flanking exonic sequences, with 4 nucleotides at 5’ end and 5 nucleotides at 3’ end, correctly spliced in a sex‐specific manner. Wild‐type and modified RTAs expressed in E. coli system retained their ability to suppress protein synthesis: 90.4% for Ricin‐WT, 71.3% for Ricin‐LERQ, and 58.0% for Ricin‐FEGQ. Embryonic injection of Acp‐CF26‐21, the RTA‐Bddsx gene driven by the actin 5C promoter, resulted in a significant increase of male percentage in the eclosed adults. Conclusion Our results indicate the RTA‐Bddsx hybrid system offers a novel and promising approach for oriental fruit fly control.
      PubDate: 2015-02-05T05:17:18.090763-05:
      DOI: 10.1002/ps.3990
       
  • Insight into the Meligethes aeneus voltage‐sensitive sodium channel
           structure and attempt to select the best pyrethroid ligands
    • Authors: Aleksandra Obrępalska‐Stęplowska; Anna Czerwoniec, Przemysęaw Wieczorek, Barbara Wrzesińska
      Abstract: Background Voltage‐sensitive sodium channel (VSSC) is a target for a pharmacological action of pyrethroids which are used in controlling pests including those of agricultural importance. Among them is the pollen beetle (Meligethes aeneus F.) – the most serious pest of Brassica napus. Due to the heavy use of pyrethroids a widespread build‐up of resistance has arisen. The main cause of pyrethroid insensitivity in M. aeneus is considered an increased oxidative metabolism, however, the additional mechanism of resistance associated with mutations in the VSSC might contribute to this phenomenon. Results We generated VSSC’s 3D model to study the docking affinities of pyrethroids to their target site within the channel. Our goal was to identify the pyrethroids which docking affinity scores are high and not affected by the potential mutations in the VSSC. We found out that the docking scores of cypermethrin are hardly influenced by appearing of point mutations. Additionally, tau‐fluvalinate, deltamethrin, bifenthrin constitute VSSC ligands with high affinity scores. Conclusions Our docking models provide information that point mutations in VSSC binding pocket might affect stability of ligands interactions and change tendencies of the ligands docking locations which might have potential effect on VSSC gating properties.
      PubDate: 2015-02-05T03:11:44.044496-05:
      DOI: 10.1002/ps.3984
       
  • Effects of Refuges on the Evolution of Resistance to Transgenic Corn by
           Western Corn Rootworm, Diabrotica virgifera virgifera LeConte
    • Authors: Jennifer Deitloff; Mike W. Dunbar, David A. Ingber, Bruce E. Hibbard, Aaron J. Gassmann
      Abstract: Background Diabrotica virgifera virgifera LeConte is a major pest of corn and causes over a billion dollars of economic loss annually through yield reductions and management costs. Corn producing toxins derived from Bacillus thuringiensis (Bt) have been developed to help manage D. v. virgifera. However, previous studies have demonstrated the ability of this species to evolve resistance to Bt toxins in both laboratory and field settings. Results We used an experimental evolution approach to test the refuge strategies for delaying resistance of D. v. virgifera to corn producing Bt toxin Cry34/35Ab1. In the absence of refuges D. v. virgifera developed resistance to Bt corn after three generations of selection. In some cases, non‐Bt refuges reduced the level of resistance compared to the strain selected in the absence of refuges, but refuge strains did show reduced susceptibility to Bt corn compared to the unselected strain. Conclusions In this study, non‐Bt refuges delayed resistance to Bt corn by D. v. virgifera in some cases but not others. Combining the refuge strategy with pyramids of multiple Bt toxins and applying other pest management strategies will likely be necessary to delay resistance of D. v. virgifera to Bt corn.
      PubDate: 2015-02-05T02:28:07.343294-05:
      DOI: 10.1002/ps.3988
       
  • Products containing microorganisms as a tool in integrated pest
           managementand the rules of their market placement in the European Union
    • Authors: Ewa Matyjaszczyk
      Abstract: Products containing microorganisms (bacteria, fungi and viruses) can be used in plant production as an intervention as well as a prevention method for pest control. Their utilization is strictly in line with the principles of integrated pest management, provided that they are effective and safe. The rules of registration of microorganisms for crop production in the European Union differ depending on if they are placed on the market as plant protection products or not. For over 20 years uniform rules for registration of plant protection products have been in force. Currently, 36 microorganisms marked up to the strain are approved for use in pest control in the Community. The decision concerning market placement of plant protection products containing approved microorganisms is issued for each Member State separately. The approaches to market placement of other products with microorganisms differ within the EU, ranging from a complete lack of requirements to long and costly registration procedures.
      PubDate: 2015-02-04T12:26:35.873658-05:
      DOI: 10.1002/ps.3986
       
  • Interference of allelopathic wheat with different weeds
    • Authors: Song‐Zhu Zhang; Yong‐Hua Li, Chui‐Hua Kong, Xiao‐Hua Xu
      Abstract: Background Interference of allelopathic wheat with weeds involves in a broad spectrum species either independently or synergistically with competitive factors. This study examined interference of allelopathic wheat with 38 weeds in relation to the production of allelochemical 2,4‐dihydroxy‐7‐methoxy‐1,4‐benzoxazin‐3‐one (DIMBOA) in wheat with and without root‐root interactions. Results There were substantial differences in weed biomass and DIMBOA concentration in wheat‐weed coexisting systems. Among 38 weeds, 9 weeds were inhibited significantly by allelopathic wheat but other 29 weeds were not. DIMBOA levels in wheat varied greatly with weed species. There was not a significant relationship between DIMBOA levels and weed‐suppressive effects. Root segregation led to great changes in weed inhibition and DIMBOA level. Compared with root contact, the inhibition of 8 weeds was lowered significantly while significant increased inhibition occurred in 11 weeds with an increased DIMBOA concentration under root segregation. Furthermore, the production of DIMBOA in wheat was induced by the root exudates from the weeds. Conclusion Interference of allelopathic wheat with weeds not only is defined as the specificity of weeds but also depends on root‐root interactions. In particular, allelopathic wheat may detect certain weeds through the root exudates and respond by increased the allelochemical, resulting in weed identity recognition.
      PubDate: 2015-02-02T02:26:34.766408-05:
      DOI: 10.1002/ps.3985
       
  • Neo‐nicotinoid induced resurgence of rice leaffolder, Cnaphalocrocis
           medinalis (Guénee)
    • Authors: Padmavathi Chintalapati; Gururaj Katti, P Raghuveer Rao, NV Krishnaiah
      Abstract: Background Among the neo‐nicotinoids, imidacloprid and thiamethoxam have been frequently used in planthopper endemic areas. Wherever leaffolder incidence occurs along with planthoppers in the rice fields, use of neo‐nicotinoids has resulted in increase in leaffolder population. The present study was carried out to verify and confirm the resurgence as well as to identify factors contributing for resurgence. Results In imidacloprid and thiamethoxam applied plots, 17.5 to 217.5 % increase in leaffolder population over untreated control was observed. Neo‐nicotinoids showed moderate toxicity to eggs with  60% survival while 37 – 60 % larvae reached adult stage. The larval duration was also reduced. There was stimulated fecundity of 6.2 to 37.21% increase over untreated control. A significant positive correlation was observed between larval population and total soluble sugars in thiamethoxam treatment (r = 0.9984, p 
      PubDate: 2015-02-02T02:11:32.303962-05:
      DOI: 10.1002/ps.3983
       
  • A floatable formulation and laboratory bioassay of Pandora delphacis
           (Entomophthoromycota: Entomophthorales) for the control of rice pest
           Nilaparvata lugens Stål (Hemiptera: Delphacidae)
    • Authors: Xiang Zhou; Xiu Su, Hongbo Liu
      Abstract: Background Brown planthoppers (BPH) Nilaparvata lugens (Stål) (Hemiptera: Delphacidae) are serious rice pests that easily develop resistance to chemical insecticides and resistant rice varieties. This study evaluated the infectivity of the BPH fungal pathogen, Pandora delphacis, and developed a novel formulation as an alternative means of BPH control. Results In the multi‐conidial concentration bioassay, P. delphacis‐infected BPH cadavers were observed on day 4, but most occurred between days 5 and 8. BPH mortality depended on the inoculated conidial concentration. The cumulative mortality of adult BPH reached 81.7% at 192 conidia mm−2 in 8 days. And inoculation with 40.9 conidia mm−2 was sufficient to induce 50% BPH death, based on the analysis of time‐concentration‐mortality model. A floatable P. delphacis‐based formulation was made for use in paddy fields; mycelium‐containing pellets mimicking mycosed cadavers could produce infectious conidia of 7–15.7 × 104 conidia pellet−1 at 11–28 °C. In the laboratory bioassay, three floating pellets in a BPH‐rearing jar caused 75.5% BPH mortality within 8 days, similar with mortality level caused by direct conidial inoculation. Conclusion P. delphacis is a potential biocontrol agent of BPH for further research, and the novel floatable formulation holds promising as a method for BPH control.
      PubDate: 2015-02-02T02:11:29.967584-05:
      DOI: 10.1002/ps.3981
       
  • Naturally occurring bioactive compounds from four repellent essential oils
           against Bemisia tabaci whiteflies
    • Authors: Emilie Deletre; Fabrice Chandre, Barbara Barkman, Chantal Menut, Thibaud Martin
      Abstract: Background In tropical countries, netting is an effective sustainable tool for protecting horticultural crops against Lepidoptera, though not against small pests like Bemisia tabaci, while smaller mesh netting can be used in temperate regions. A solution is to combine a net with a repellent. Previously we identified repellent essential oils: lemongrass (Cymbopogon citratus), cinnamon (Cinnamomum zeylanicum), cumin (Cuminum cyminum) and citronella (Cymbopogon winternarius). The present study was designed to identify the active compounds of these essential oils, characterize their biological activity, and examine their potential for coating nets. We investigated the efficiency and toxicity of nets dipped in different solutions. We then studied the repellent effect with an olfactometer and the irritant effect by videotracking. Results Geraniol and citronellol were the most promising net coatings due to their repellent effect. The repellency, irritancy or toxicity varied with the product and concentration and these features were independent, indicating that the repellent and the irritant/toxic mechanisms were not the same. The combined effects of these different compounds account for the bioactivity of the mixture, suggesting interactions between the compounds. Conclusion This new sustainable strategy for protecting vegetable crops against whiteflies is discussed, in addition to the use of companion plants that could produce such bioactive compounds.
      PubDate: 2015-02-02T02:10:58.748534-05:
      DOI: 10.1002/ps.3987
       
  • Evaluation of a model community‐wide bed bug management programin
           affordable housing
    • Authors: Richard Alan Cooper; Changlu Wang, Narinderpal Singh
      Abstract: Background Low income apartment communities in the U.S. are suffering from disproportionally high bed bug, Cimex lectularius L., infestations due to lack of effective monitoring and treatment. Studies examining the effectiveness of integrated pest management (IPM) for the control of bed bugs in affordable housing have been limited to small subsets of bed bug infested apartments, rather than at the apartment community‐level. We developed, implemented, and evaluated a complex‐wide IPM program for bed bugs in an affordable housing community. Proactive inspections and biweekly treatments using a combination of nonchemical and chemical methods until bed bugs were not detected for three biweekly monitoring visits were key elements of the IPM program. Results A total of 55 bed bug infested apartments were identified during the initial inspection. Property management was unaware of 71% of these infestations. Over the next 12 mo, 14 additional infested apartments were identified. The IPM program resulted in a 98% reduction in bed bug counts among treated apartments and reduced infestation rates from 15% to 2.2% after 12 mo. Conclusions Adopting a complex‐wide bed bug IPM program, incorporating proactive monitoring, and biweekly treatments of infested apartments utilizing nonchemical and chemical methods can successfully reduce infestation rates to very low levels.
      PubDate: 2015-01-31T04:43:46.330079-05:
      DOI: 10.1002/ps.3982
       
  • Understanding trophic interactions of Orius spp. (Hemiptera: Anthocoridae)
           in lettuce crops by molecular methods
    • Authors: Priscila Gomez‐Polo; Oscar Alomar, Cristina Castañé, Thaïs Aznar‐Fernández, Jonathan G Lundgren, Josep Piñol, u Agustí
      Abstract: Background The aphid Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) and the thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) are common pests in Mediterranean lettuce crops, where Orius spp. are common generalist predators. Predation by Orius spp. was studied in a lettuce plot by conventional PCR and real‐time PCR analyses using specific primers of both main pests. Also high‐throughput sequencing was used to have a wider approach of the diet of these predators in natural field conditions. Results Molecular analyses indicated a higher predation on N. ribisnigri in spring and on F. occidentalis in summer. Predation on alternative prey, like Collembola, was also found in both seasons. Real‐time PCR was more sensitive than conventional PCR in showing the target trophic links, whereas high‐throughput sequencing revealed predation on other natural enemies (Intraguild Predation (IGP)), showing other trophic interactions of Orius majusculus within the studied ecosystem. Conclusions This study gives important information about the trophic relationships present in Mediterranean lettuce crops in different periods of the year. The detected predation by Orius spp. on alternative prey, as well as on other natural enemies should be further investigated to clarify whether it adds or detracts to the biological control of N. ribisnigri and F. occidentalis.
      PubDate: 2015-01-31T04:31:15.207861-05:
      DOI: 10.1002/ps.3989
       
  • Acaricidal activity of compounds from Cinnamomum camphora (L.) Presl
           against the carmine spider mite, Tetranychus cinnabarinus
    • Authors: Yijuan Chen; Guanghui Dai
      Abstract: BACKGROUND Tetranychus cinnabarinus (Boisduval) is one of the most important, highly polyphagous pests of a wide range of field and greenhouse crops throughout the world. The control of this mite is still based primarily on the use of synthetic chemical pesticides. In this study, we screened eight plant extracts from China and evaluated the natural compounds showing acaricidal properties from the plant extract, considering their potential use as an alternative to synthetic pesticides. RESULTS In bioassay screening assays, the Cinnamomum camphora (L.) Presl extract showed significantly greater acaricidal activity against T. cinnabarinus than the other seven plant extracts tested. Five compounds were identified from the C. camphora extract via repeated column chromatography and gas chromatography–mass spectrometry analysis. All the compounds presented acaricidal activity, with 2,4‐di‐tert‐butylphenol and ethyl oleate exhibiting the greatest activity. At 7 days after treatment in a potted seedling experiment, the LC50 values of 2,4‐di‐tert‐butylphenol and ethyl oleate were found to be 1850.94 and 2481.65 mg kg−1 respectively. Microscopic observations showed that the mites displayed the symptomology of poisoning. CONCLUSION These results demonstrated that the C. camphora extract and its two active components show the potential to be developed as new natural acaricides for controlling carmine spider mites. © 2014 Society of Chemical Industry
      PubDate: 2015-01-22T06:37:12.171106-05:
      DOI: 10.1002/ps.3961
       
  • Field‐evolved resistance to imidacloprid and ethiprole in
           populations of brown planthopper Nilaparvata lugens collected from across
           South and East Asia
    • Authors: William T. Garrood; Christoph T. Zimmer, Kevin J. Gorman, Ralf Nauen, Chris Bass, T.G. Emyr Davies
      Abstract: Background We report on the status of imidacloprid and ethiprole resistance in Nilaparvata lugens Stål collected from across South and East Asia over the period 2005–2012. Results A resistance survey found that field populations had developed up to 220‐fold resistance to imidacloprid and 223‐fold resistance to ethiprole, and that many of the strains collected showed high levels of resistance to both insecticides. We also found that the cytochrome P450 CYP6ER1 was significantly overexpressed in 12 imidacloprid resistant populations tested when compared to a laboratory susceptible strain, with fold changes ranging from 10‐90‐fold. In contrast another cytochrome P450 CYP6AY1, also implicated in imidacloprid resistance, was under expressed in 10 of the populations and only significantly overexpressed (3.5‐fold) in a single population from India compared to the same susceptible strain. Further selection of two of the imidacloprid resistant field strains correlated with an approximate 3‐fold increase in expression of CYP6ER1. Conclusions We conclude that overexpression of CYP6ER1 is associated with field evolved resistance to imidacloprid in brown planthopper populations in five countries in South and East Asia.
      PubDate: 2015-01-22T02:04:09.512654-05:
      DOI: 10.1002/ps.3980
       
  • Spatial separation of semiochemical Lurem‐TR and entomopathogenic
           fungi to enhance their compatibility and infectivity in an autoinoculation
           system for thrips management
    • Authors: D.K. Mfuti; S. Subramanian, R.W.H.M. Tol, G.L. Wiegers, W.J. Kogel, S. Niassy, H. Plessis, S. Ekesi, N.K. Maniania
      Abstract: Background The effect of spatial separation of the semiochemical Lurem‐TR, which has been found to inhibit conidia of entomopathogenic fungi when put together, on the persistence of conidia of Metarhizium brunneum and M. anisopliae was evaluated in the greenhouse and field in order to develop an autodissemination strategy for the management of Megalurothrips sjostedti on cowpea crop. Influence of spatial separation of the semiochemical on thrips attraction and conidial acquisition by thrips from the autoinoculation device was also investigated in the field. Results Persistence of conidia of M. brunneum and M. anisopliae increased with distance of separation of Lurem‐TR. Direct exposure of fungus without separation from Lurem‐TR recorded the lowest conidial germination as compared to the other treatments. Attraction of thrips to the device also varied significantly according to distance between device and semiochemical, with a higher number of thrips attracted when Lurem‐TR was placed in a container below the device and at 10 cm distance. There was no significant difference in conidial acquisition between spatial separation treatments of conidia and Lurem‐TR. Attraction of other insect pests to the device did not significantly vary between treatments. Positive correlations were found between conidial acquisition and thrips attraction. Conclusion This study suggests that spatial separation of fungal conidia from Lurem‐TR in an autoinoculation device could provide a low‐cost strategy for effective management of thrips in grain legume cropping systems.
      PubDate: 2015-01-21T04:32:12.635337-05:
      DOI: 10.1002/ps.3979
       
  • Nematicidal activity of acetophenones and chalcones against Meloidogyne
           incognita and structure‐activity considerations
    • Authors: Pierluigi Caboni; Nadhem Aissani, Monica Demurtas, Nikoletta Ntalli, Valentina Onnis
      Abstract: Background With the ultimate goal of identifying new compounds active against root‐knot nematodes, a set of 14 substituted chalcones were synthesised starting from acetophenones. These chalcones and various acetophenones were tested in vitro against Meloidogyne incognita. Results The most potent acetophenones were 4‐nitroacetophenone and 4‐iodoacetophenone with EC50/24h values of 12 ± 5 and 15 ± 4 mg/L, respectively, somewhat weaker than that of the chemical control fosthiazate in our previous experiments (EC50/24h 0.4 ± 0.3 mg/L). When we converted the acetophenones to chalcones, the nematicidal activity differed based on their substitution pattern. The condensation of 4‐nitroacetophenone with 2,4,6‐trihydroxybenzaldehyde to give the corresponding chalcone (E)‐1‐(4‐nitrophenyl)‐3‐(2,4,6‐trihydroxyphenyl)prop‐2‐en‐1‐one (11) led to a slight reduction in activity (EC50/24h value 25 ± 17 mg/L). Moreover, (E)‐3‐(2‐hydroxy‐5‐iodophenyl)‐1‐(4‐methoxyphenyl)prop‐2‐en‐1‐one (26) showed better activity (EC50/24h value 26 ± 15 mg/L) when compared to 4‐methoxyacetophenone cphEC50/24h value 43 ± 10 mg/L). Conclusions Acetophenones and chalcones may represent good leads in the discovery of new nematicidal compounds and may have potential use in crop management as active ingredients.
      PubDate: 2015-01-16T03:03:04.308617-05:
      DOI: 10.1002/ps.3978
       
  • A qPCR‐based method for detecting parasitism of Fopius arisanus
           (Sonan) in oriental fruit flies, Bactrocera dorsalis (Hendel)
    • Authors: Guanghong Liang; Eric B Jang, Wade C. Heller, Chiou Ling Chang, Jiahua Chen, Feiping Zhang, Scott M. Geib
      Abstract: Background Parasitism detection and species identification are necessary in fruit fly biological control. Currently release of mass‐reared Fopius arisanus is occurring world‐wide, as which is effective in controlling Bactrocera dorsalis and Ceratitis capitata. To detect and assess parasitism in parasitoid mass‐rearing colonies and parasitism levels in field populations across all life stages of hosts, the development of a rapid, specific and sensitive method is important. Results A species‐specific probe was designed for F. arisanus, as well as one universal Tephritid probe. Utilizing rapid DNA extraction techniques coupled with quantitative‐PCR, a simple and fast assay has been developed to detect parasitism of F. arisanus that is sensitive enough to detect the parasitoid across all developmental stages including a single egg per host egg or 0.25 ng/40 ng (parasitoid/host DNA). The qPCR methods also detect a higher parasitism rate when compared to rearing‐based methods where parasitism rate is based off of wasp emergence, where un‐emerged wasps are not included. Conclusion This method is a rapid, sensitive, and specific technique to determine the parasitism rate of F. arisanus across all life stages of B.dorsalis, which will be useful to predict parasitoid output from mass‐rearing and evaluate the outcome of pest suppression after mass‐releasing in the fields.
      PubDate: 2015-01-14T01:21:23.025688-05:
      DOI: 10.1002/ps.3976
       
  • Evaluation of alternative Plutella xylostella control by two Isaria
           fumosorosea conidia formulations, oil‐based formulation and wettable
           powder combined with Bacillus thuringiensis
    • Authors: Xiao‐ge Nian; Yu‐rong He, Li‐hua Lu, Rui Zhao
      Abstract: Background Entomopathogenic fungi are potential candidates for controlling Plutella xylostella. The control efficacy of two I. fumosorosea conidia formulations, wettable powder and oil‐based formulation, combined with B. thuringiensis against P. xylostella, was tested. Results In the laboratory, the combined application of two pathogens increased larval mortality either in an additive or a synergistic way. P. xylostella larvae treated with oil‐based formulation died sooner than larvae infected with wettable powder. For pot and field experiments, each formulation was applied alone or combined with B. thuringiensis 668 µg mL−1, then larval mortality, pupation rate, adult emergence rate, female longevity and fecundity were recorded. In pot experiment, there was no evidence of any antagonistic effects between the two pathogens. The combined treatments of B. thuringiensis with high concentration of two I. fumosorosea formulations resulted in higher mortality (84.4 % and 86.2 %) with minimum pupation (15.6 % and 11.9 %) and adult emergency rates (8.7 % and 7.0 %). Female longevity and fecundity were significantly decreased by two formulations at high concentration compared to the control. Similar results were also observed in field experiment. Conclusion The combined application of I. fumosorosea and B. thuringiensis is a promising alternative strategy for P. xylostella control.
      PubDate: 2015-01-14T01:21:06.88927-05:0
      DOI: 10.1002/ps.3977
       
  • Should I fight or should I flight? How studying insect aggression can
           help Integrated Pest Management
    • Authors: Giovanni Benelli
      Abstract: Aggression plays a key role all across the Animal Kingdom, as it allows the acquisition and/or defence of limited resources (food, mates and territories) in a huge number of species. A large part of our knowledge on aggressive behaviour has been developed on insects of economic importance. How can this knowledge be exploited to enhance Integrated Pest Management? Here, I highlight how knowledge on intra‐specific aggression can help IPM both in terms of insect pests (with a focus on the enhancement of the Sterile Insect Technique), and biological control agents (with a focus on mass‐rearing optimisation). Then, I examine what implications for IPM can be outlined from knowledge about inter‐specific aggressive behaviour. Besides predator‐pest aggressive interactions predicted by classic biological control, I focus on what IPM can learn from (i) inter‐specific aggression among pest species (with special reference to competitive displacement), (ii) defensive behaviour exhibited by prey against predaceous insects, and (iii) conflicts among predaceous arthropods sharing the same trophic niche (with special reference to learning/sensitisation practices and artificial manipulation of chemically‐mediated interactions).
      PubDate: 2015-01-13T01:45:59.855255-05:
      DOI: 10.1002/ps.3974
       
  • Effects of methoprene, a juvenile hormone analog, on survival of various
           developmental stages, adult emergence, reproduction, and behavior of Asian
           citrus psyllid, Diaphorina citri Kuwayama
    • Authors: Gurpreet S. Brar; Wendy Meyer, Lukasz L. Stelinski
      Abstract: Background The Asian citrus citrus psyllid, Diaphorina citri Kuwayama, transmits a bacterium that causes huanglongbing in citrus. Frequent and repeated use of neurotoxic insecticides against D. citri has resulted in development of insecticide resistance. We evaluated the effects of the juvenile hormone analog, methoprene, on egg hatch, nymphal development, adult emergence, reproduction, and behavior of D. citri. Results Methoprene significantly reduced viability of eggs that were between 0–4 days old. Egg hatch of 0–48 h and 49–96 h old eggs was 8% and 9% respectively, when treated with 320 µg ml −1 of methoprene. Methoprene caused significant mortality of first, third and fifth instar D. citri nymphs and reduced adult emergence as compared with controls. Methoprene caused less than 5% adult emergence when first and third instar stages were treated, respectively, and less than 40% adult emergence when fifth instars were treated. Reduced fertility of females was observed when they emerged from methoprene‐treated fifth instars. Conclusion Methoprene was effective in reducing egg hatch, suppressing nymphal development, and decreasing adult emergence of D. citri under laboratory conditions. Treatment of fifth instars reduced fertility of females. Methoprene might be a possible tool for integrated management of D. citri.
      PubDate: 2015-01-13T01:45:57.570156-05:
      DOI: 10.1002/ps.3975
       
  • Evaluation of diamide insecticides co‐applied with other
           agrochemicals at various times to manage Ostrinia nubilalis in processing
           snap bean
    • Authors: Anders S. Huseth; Russell L. Groves, Scott A. Chapman, Brian A. Nault
      Abstract: Background Multiple applications of pyrethroid insecticides are used to manage European corn borer, Ostrinia nubilalis Hübner, in snap bean, but new diamide insecticides may reduce application frequency. In a 2‐year, small‐plot study, O. nubilalis control was evaluated by applying cyantraniliprole (diamide) and bifenthrin (pyrethroid) insecticides at one of three phenological stages (bud, bloom, pod formation) of snap bean development. Co‐application of these insecticides with either herbicides or fungicides was also examined as a way to reduce the total number of sprays during a season. Results Cyantraniliprole applications timed either during bloom or pod formation controlled O. nubilalis better than similar timings of bifenthrin. Co‐applications of insecticides with fungicides controlled O. nubilalis as well as insecticide applications alone. Insecticides applied either alone or with herbicides during bud stage did not control this pest. Conclusion Diamides are an alternative to pyrethroids for the management of O. nubilalis in snap bean. Adoption of diamides by snap bean growers could improve the efficiency of production by reducing the number of sprays required each season.
      PubDate: 2015-01-13T01:45:43.110295-05:
      DOI: 10.1002/ps.3973
       
  • Lethal and behavioral effects of selected novel pesticides on adults of
           Trichogramma pretiosum (Trichogrammatidae: Hymenoptera)
    • Authors: Muhammad Ashraf Khan; Hizbullah Khan, John R. Ruberson
      Abstract: Background Growing demand for reduced chemical inputs in agricultural systems requires more effective integration of biological control with pesticides. The egg parasitoid Trichogramma pretiosum Riley is an important natural enemy of lepidopteran pests, used in biological control. We studied interaction of T. pretiosum and pesticides: 1) acute toxicity of 19 pesticides (insecticides, miticides, fungicides, herbicides) to adult parasitoids, and 2) behavioral effects of 11 pesticides on foraging parasitoid females, including host antennation, stinging, and host feeding. Results At recommended field doses, fipronil, dinotefuran, spinetoram, tolfenpyrad, and abamectin induced nearly 100% adult mortality within 24 hour of exposure to treated cotton leaves compared to controls. Acetamiprid was also toxic, but significantly less than the former materials. The other pesticides had no significant toxic effects. Only glufosinate ammonium exhibited increased toxicity among the non‐toxic materials when increased 2‐ or 4‐fold over recommended rates. Foraging behavior of parasitoids was affected only by tolfenpyrad among materials tested. Conclusion Most novel pesticides, except several insecticides, exhibited little to no acute toxicity to the parasitoid. Parasitoid foraging behavior was only affected by tolfenpyrad, indicating that parasitoids could successfully forage on eggs treated with most evaluated. Therefore, many of these pesticides may have good compatibility with Trichogramma.
      PubDate: 2015-01-07T23:55:03.767725-05:
      DOI: 10.1002/ps.3972
       
  • Inheritance, fitness costs, incomplete resistance and feeding preferences
           in a laboratory‐selected MON810‐resistant strain of the true
           armyworm Mythimna unipuncta
    • Authors: M. García; F. Ortego, P. Hernández‐Crespo, G. P. Farinós, P. Castañera
      Abstract: BACKGROUND The low efficacy of MON810 maize against Mythimna unipuncta represents a scenario of not compliance with the “high‐dose” strategy, raising concerns on the potential resistance development and outbreaks of this secondary pest. The present study offers insight into the different components related to resistance in the laboratory‐selected MON810‐resistant (MR) strain of M. unipuncta. RESULTS The resistance in the MR strain is autosomal and inherited as a partially dominant trait. We have found a lack of fitness costs in this strain for essential life history traits, reproductive potential and on most of the population growth parameters analyzed, with the only exception of an increment in the mean generation time. Larvae of the MR strain reared on Bt maize took longer to develop, presented a high adult cumulative emergence time and had lower growth rate than those reared on non‐Bt maize, suggesting the existence of incomplete resistance. Feeding preferences assays reveal a low discrimination between Bt and conventional maize. CONCLUSION Both resistant and heterozygous larvae of M. unipuncta survive to the Cry1Ab toxin expressed on Bt maize, with a weak fitness‐cost for the homozygous, indicating the potential risk for field‐evolved resistance and its relevance for resistance monitoring.
      PubDate: 2015-01-07T02:22:01.927061-05:
      DOI: 10.1002/ps.3971
       
  • Isolation and characterization of a Sphingomonas strain able to degrade
           the fungicide ortho‐phenylphenol
    • Authors: Chiara Perruchon; Vasiliki Patsioura, Sotirios Vasileiadis, Dimitrios G. Karpouzas
      Abstract: Background Ortho‐phenylphenol (OPP) is a fungicide used in fruit‐packaging plants for the control of fungal infestations during storage. Its application leads to the production of large wastewater volumes which according to the European legislation should be treated on site. Despite this, no efficient treatment systems are currently available and the development of biological systems based on tailored‐made pesticide‐degrading inocula for the treatment of those wastewaters is an appealing solution. Results Enrichment cultures from a soil collected from a wastewater disposal site resulted in the isolation of a pure Sphingomonas haloaromaticamans strain P3 able to rapidly degrade OPP and use it as an energy source. Its degrading capacity was dependent on the external supply of amino acids or on the presence of other bacteria which did not contribute to fungicide degradation. The isolated S. haloaromaticamans strain was able to metabolize up to 150 mg L−1 OPP within 7 days, in a wide range of pH (4.5‐9) and temperatures (4‐37°C), and in the presence of other pesticides (thiabendazole and diphenylamine) co‐used in the fruit‐packaging industry. Conclusion Overall, the OPP‐degrading bacterium isolated showed high potential for use in future biodepuration treatment systems and bioremediation strategies.
      PubDate: 2015-01-02T01:47:58.621174-05:
      DOI: 10.1002/ps.3970
       
  • Current and future status of the use of transgenes for pest management
    • Authors: Stephen O. Duke
      Pages: 643 - 644
      PubDate: 2015-04-02T08:06:53.996477-05:
      DOI: 10.1002/ps.4002
       
  • Efficacy of an alphabaculovirus‐based biological insecticide for
           control of Chrysodeixis chalcites (Lepidoptera: Noctuidae) on tomato and
           banana crops
    • Authors: Oihane Simón; Alexandra Bernal, Trevor Williams, Aurelio Carnero, Estrella Hernández‐Suárez, Delia Muñoz, Primitivo Caballero
      Abstract: Background Chrysodeixis chalcites (Esper) is a major pest of tomato in Mediterranean countries and attacks banana in the Canary Islands (Spain). The efficacy of Chrysodeixis chalcites single nucleopolyhedrovirus (ChchSNPV‐TF1) was evaluated in plant growth‐chambers and greenhouse trials performed on tomato and banana plants, respectively. Treatments were applied using a compressed air sprayer. Results Mean (±SE) lethal infection varied from 77 ± 10 to 94 ± 3% in second instar larvae fed for two days on tomato plants treated with 2x106 to 5x107 virus occlusion bodies (OBs)/L; increasing to ~100% infection after 7 days. Mortality of larvae collected from banana at different intervals post‐application varied from 54 ± 10 to 96 ± 4% in treatments involving 1x108‐1x109 OBs/L, whereas indoxacarb (Steward 30% WG) and Bacillus thuringiensis var. kurstaki (Biobit 16% WP) treatments produced between 22 ± 6 and 32 ± 5% pest mortality. All treatments significantly reduced plant defoliation compared with untreated controls. Application of 1x109 OBs/L was 3 to 4‐fold more effective than chemical or B. thuringiensis treatments. Larvae acquired lethal infection more rapidly when feeding on tomato than banana plants, but this difference disappeared following >60 minutes of feeding. Conclusion This information should prove useful in the registration of ChchSNPV‐TF1 as a bioinsecticide in the Canary Islands and Europe.
      PubDate: 2014-12-23T03:42:33.538579-05:
      DOI: 10.1002/ps.3969
       
  • Mechanisms of glyphosate resistance in two perennial ryegrass (Lolium
           perenne) populations
    • Authors: Hossein Ghanizadeh; Kerry C. Harrington, Trevor K. James, David J. Woolley, Nicholas W. Ellison
      Abstract: Background Perennial ryegrass (Lolium perenne) has developed resistance to glyphosate within New Zealand vineyards following many years of herbicide application. The objectives of this work were to confirm resistance within two populations obtained from affected vineyards and to determine the mechanism of resistance to glyphosate. Results Population O was confirmed to have a 25‐fold resistance to glyphosate whereas Population J had a 7‐fold resistance. Results of genotyping assays demonstrated a single nucleotide substitution at Codon 106 of EPSPS in Population O but not Population J. Glyphosate resistant and susceptible populations did not differ in glyphosate absorption. However, in both resistant populations, much more of the absorbed 14C‐glyphosate remained in the treated leaf than occurred in the susceptible population. Significantly more glyphosate was found in the pseudostem region of susceptible plants than resistant plants. Conclusion Both target site and non‐target site mechanisms of glyphosate resistance were found in the perennial ryegrass population with 25‐fold resistance, whereas only the non‐target site mechanism of resistance was found in the population with 7‐fold resistance. This is first study of the mechanism of glyphosate resistance in perennial ryegrass.
      PubDate: 2014-12-23T03:06:01.818101-05:
      DOI: 10.1002/ps.3968
       
  • Behavior-modifying compounds for management of the red palm weevil
           (Rhynchophorus ferrugineus Oliver)
    • Authors: Salvatore Guarino; Stefano Colazza, Ezio Peri, Paolo Lo Bue, Tatiana Kuznetsova, Galina Gindin, Victoria Soroker
      Abstract: Background Populations of red palm weevil (RPW), a severe pest of palms in Mediterranean countries, might be limited by semiochemical-based behavior-disrupting methods. We evaluated the effects of electroantennogram (EAG)-active plant volatiles on the behavior of RPWs from Italy and Israel. In field experiments, α-pinene, citronellol, geraniol, citral and 1-octen-3-ol were tested for their ability to disrupt attraction to pheromone–kairomone traps. Those that were found disruptive in the field were evaluated in a laboratory choice bioassay in individual cages for their effect on RPW female feeding and oviposition. Results Field experiments showed reduced captures in traps loaded with geraniol (−57%), 1-octen-3-ol (−50%) or α-pinene (−45% to −60%); captures in citronellol- or citral-loaded traps did not differ from controls. In laboratory experiments, 1-octen-3-ol was the most potent behavior-modifying compound, eliciting a significant/marginally significant reduction in both feeding and oviposition at the lowest dose tested in both populations. Geraniol generally caused a strong reduction of feeding and oviposition at each dose tested (Israel), or at the highest dose (Italy). α-pinene caused some reduction of feeding activity at the highest dose tested (Italy), but no consistent repellency (Israel). Conclusion Field and laboratory data suggest the potential for the use of 1-octen-3-ol, geraniol and α-pinene for RPW population management.
      PubDate: 2014-12-18T15:37:50.124033-05:
      DOI: 10.1002/ps.3966
       
  • Stopped in its tracks: How λ-cyhalothrin can break the aphid
           transmission of a potato potyvirus
    • Authors: Brian Fenton; Thomas Salter, Gaynor Malloch, Graham Begg, Eric Anderson
      Abstract: Background Pyrethroids are one of the most widespread and commonly used classes of insecticide and they are used in multiple roles including protecting potato crops from virus vector aphids. Resistance in some genotypes of a few species is now widespread but most species remain susceptible. The rate of virus transmission by two genotypes of the peach potato aphid, Myzus persicae, fed on Potato Virus Y-infected leaves of potato treated with the pyrethroid, lambda-cyhalothrin, was evaluated. Results The susceptible genotype, type J, was significantly inhibited from transmitting virus to uninfected seedlings. A genotype containing the M918L super knock down resistance mutation conferring resistance to pyrethroids, type O, showed no inhibition of transmission. However, when survival of the aphids after exposure was compared, the pyrethroid had not killed the type J aphids. Conclusions λ-cyhalothrin in a commercial formulation disrupts PVY transmission by disorientating aphid vectors for a sufficient time that the virus loses its transmissibility. However, M. persicae genotypes carrying the M918L mutation are not prevented from transmitting.
      PubDate: 2014-12-18T15:08:35.152425-05:
      DOI: 10.1002/ps.3967
       
  • Larvicidal activity of the essential oil from Tetradium glabrifolium
           fruits and its constituents against Aedes albopictus
    • Authors: Xin Chao Liu; Qiyong Liu, Xu Bo Chen, Ligang Zhou, Zhi Long Liu
      Abstract: Background In our screening program for new agrochemicals from wild plants, the essential oil of Tetradium glabrifolium (Champ. ex Benth.) T.G. Hartley fruits was found to possess strong larvicidal activity against the Asian tiger mosquito, Aedes albopictus L. The essential oil was extracted via hydrodistillation and their constituents were determined by GC‐MS analysis. The active compounds were isolated and identified by bioassay‐directed fractionation. Results GC/MS analyses revealed the presence of 19 components with 2‐tridecanone (43.38%), 2‐undecanone (24.09%), d‐limonene (13.01%), caryophyllene (5.04%) and β‐elemene (4.07%) being the major constituents. Based bioactivity‐directed chromatographic separation of the oil led to the isolation of 2‐tridecanone, 2‐undecanone and d‐limonene as active compounds. The essential oil of T. glabrifolium exhibited larvicidal activity against the early fourth instar larvae of A. albopictus with an LC50 value of 8.20 µg/ml. The isolated constituent compounds, 2‐tridecanone, 2‐undecanone and d‐limonene possessed strong larvicidal activity against the early fourth instar larvae of A. albopictus with LC50 values of 2.86 µg/ml, 9.95 µg/ml and 41.75 µg/ml, respectively. Conclusion The findings indicated that the essential oil of T. glabrifolium fruits and the three constituents have an excellent potential for use in control of A. albopictus larvae and could be useful in search of newer, safer and more effective natural compounds as larvicides.
      PubDate: 2014-12-13T00:33:36.474818-05:
      DOI: 10.1002/ps.3964
       
  • Foraging activity of commensal Mus musculus in semicaptivity conditions.
           Effect of predator odours, previous experience and moonlight
    • Authors: María Busch; Nora E Burroni
      Abstract: Background Mus musculus is a pest in urban and rural habitats where it consumes and contaminates food and may transmit diseases to human and domestic animals. Its control by anticoagulants is partially effective because of aversive behaviours and resistance. In this context, we wanted to assess the potential of the use of predator odours as repellents in experimental feeding trials using urine and faeces of domestic cats and faeces of geoffroyi cat, a wild small felid that is one of the main rodent predators in the study area. We also assessed the effect of previous experience and moonlight on foraging activity. Results We did not find an aversive response to cat odours in Mus musculus individuals. There was a trend to consume food in the same feeding stations along time and the visit rate was lower in periods with high moonlight than in periods with low moonlight. Conclusions Predator odours did not seem to be useful as rodent repellents but maintaining illumination may lower rodent foraging activity. As rodents maintain their feeding sites along time toxic baits may be more efficiently placed at sites previously known to be used by rodents.
      PubDate: 2014-12-10T03:36:26.502245-05:
      DOI: 10.1002/ps.3962
       
  • Effect of formulation and repeated applications on the enantioselectivity
           of metalaxyl dissipation and leaching in soil
    • Authors: Rafael Celis; Beatriz Gámiz, María A Adelino, Juan Cornejo, María C Hermosín
      Abstract: Background Soil incubation and column leaching experiments were conducted to address the question of whether the type of formulation (unsupported vs clay‐supported) and repeated applications of the chiral fungicide (RS)‐metalaxyl affected the enantioselectivity of its dissipation and leaching in a slightly alkaline, loamy sand agricultural soil. Results Regardless of the type of formulation and the number of fungicide applications, the R‐enantiomer of metalaxyl was degraded faster than the S‐enantiomer, but the individual degradation rates of R‐ and S‐metalaxyl were highly affected by the different application regimes assayed (t1/2 = 2–104 days). Repeated applications accelerated the degradation of the biologically‐active R‐metalaxyl enantiomer, whereas they led to slower degradation of the non‐active S‐metalaxyl enantiomer. The type of formulation influenced less the dissipation rates of the enantiomers. For all formulations tested, soil column leachates became more and more enriched in S‐enantiomer as the number of fungicide applications was increased, and application of metalaxyl to soil columns as clay‐based formulations reduced the leaching of both enantiomers. Conclusion Pesticide application conditions can greatly influence the enantioselective dissipation of chiral pesticides in soil, and hence, are expected to exert a great impact on both the biological efficacy and the environmental chiral signatures of pesticides applied as mixtures of enantiomers or racemates to agricultural soils.
      PubDate: 2014-12-10T03:35:43.097083-05:
      DOI: 10.1002/ps.3963
       
  • Comparisons of antifeedancy and spatial repellency of three natural
           product repellents against horn flies, Haematobia irritans (Diptera:
           Muscidae)
    • Authors: Junwei J Zhu; Gary J Brewer, David J Boxler, Kristina Friesen, David B Taylor
      Abstract: Background Horn flies are among the most important biting fly pests of cattle in the United States. Horn fly management is largely dependent upon pesticides, which ultimately leads to the rapid development of insecticide resistance. Alternative control strategies, including repellents, have shown promising results in reducing fly biting. In the present study, we examined the efficacy and longevity of recently identified natural product repellents against horn flies. Results Catnip oil, geraniol and C8910 acids reduced horn fly feeding in a laboratory bioassay and also exhibited spatial repellency in the olfactometer. Residual activity was observed for up to 3 days in laboratory assays, however, 24 hours of residual effectiveness was observed from the two repellents when applied on cattle in the field. The limited residual effectiveness was correlated to the high volatility of the major active repellent compounds. Conclusion All three natural product repellents effectively repel biting horn flies, exhibiting both feeding deterrence and spatial repellency. They may be used for developing an effective Push‐Pull strategy with a slow release matrix that can prolong their effectiveness for horn fly management.
      PubDate: 2014-12-10T03:35:34.585849-05:
      DOI: 10.1002/ps.3960
       
  • Geographical distribution and frequencies of
           organophosphate‐resistant Ace alleles and morphometric variations in
           olive fruit fly populations
    • Authors: Ersin Doğaç; İrfan Kandemir, Vatan Taskin
      Abstract: BACKGROUND In the Mediterranean basin organophosphate (OP) insecticides have been used intensively to control olive fly populations. Acetylcholinesterase (Ace) is the molecular target of OP insecticides, and three resistance‐associated mutations that confer different levels of OP insensitivity have been identified. In this study, genotypes of olive fly Ace were determined in field‐collected populations from broad geographical areas in Turkey. In addition, the levels of asymmetry of wing and leg characters were compared in these populations. RESULTS Our study revealed the existence of a genetically smooth stratification pattern in OP resistance allele distribution in the olive fly populations of Turkey. In contrast to earlier findings, the frequency of Δ3Q was found to be lower in the Aegean region, where the populations have been subjected to high selection pressure. Results based on the morphological differences among the samples revealed a similar pattern for both sides and did not demonstrate a clear separation. CONCLUSION The frequencies and geographic range of resistance alleles indicate that they were selected in the Aegean coast of Turkey and then spread westward towards Europe. One possible explanation for the absence of morphological asymmetry in olive fly samples might be the presence of modifier allele(s) that compensates for the increase in asymmetry.
      PubDate: 2014-12-10T02:51:51.289633-05:
      DOI: 10.1002/ps.3958
       
  • Impact of the goldspotted oak borer, Agrilus auroguttatus, on the health
           of coast live oak before and after treatment with two systemic
           insecticides
    • Authors: Yigen Chen; Mary L. Flint, Tom W. Coleman, Joseph J. Doccola, Donald M. Grosman, David L. Wood, Steven J. Seybold
      Abstract: BACKGROUND The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego Co., CA, USA. From two sites in the core area of the infestation, we report a 2.5‐yr investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic insecticides, emamectin benzoate (EB) and imidacloprid (IC). RESULTS None of the 446 survey trees died during the study. The crown dieback rating of most trees at both study sites remained unchanged, regardless of insecticide treatment. A higher cumulative increase in the number of A. auroguttatus emergence holes was observed on trees that were previously infested and on trees with larger diameters. Over the 2.5‐yr, the new infestation rates of initially uninfested trees across the untreated and treated groups were 50% (EB) and 32% (IC), and neither EB nor IC treatment affected cumulative increases in the number of emergence holes. EB‐injected trees did not have significant annual increases in the number of A. auroguttatus emergence holes at either 1.5 or 2.5 yr compared to that at 0.5 yr, whereas untreated trees had significant annual increases. Although IC‐injected trees had a significantly greater annual increment in the number of emergence holes than untreated trees during the last year of the study, treated trees had significant reductions in annual increases in emergence holes at both 1.5 and 2.5 yr compared to that at 0.5 yr. Untreated trees had no significant reduction in the annual increase in emergence holes at 1.5 and 2.5 yr. CONCLUSIONS Agrilus auroguttatus preferentially attacked previously infested and larger (DHB > 30 cm) oak trees, but the attacks led to very gradual changes in the health of the trees. Both EB and IC provided minor suppressive effects on A. auroguttatus emergence.
      PubDate: 2014-12-09T10:39:08.479255-05:
      DOI: 10.1002/ps.3959
       
  • Chemical Control of the Asian Citrus Psyllid and of Huanglongbing Disease
           in Citrus
    • Authors: Dhana Raj Boina; Jeffrey R. Bloomquist
      Abstract: By 2014, Huanglongbing (HLB), the most destructive disease of citrus, and its insect vector, the Asian citrus psyllid (ACP), Diaphorina citri (Kuwayama), became established in all major citrus growing regions of the world including the United States of America (USA), with the exception of California. At present, application of insecticides is the most widely followed option for reducing ACP populations, while application of antibiotics for suppressing HLB disease/symptoms is being practiced in some citrus growing regions. Application of insecticides during the dormant winter season, along with cultivation of HLB‐free seedlings and early detection and removal of symptomatic and asymptomatic trees has been very effective in managing ACP. Area‐wide management of ACP by application of insecticides at low‐volume in large areas of citrus cultivation, has been shown to be effective in managing HLB and reducing management costs. Since insecticide resistance is a major problem in sustainable management of ACP, rotation/alternation of insecticides with different chemistries and modes of action needs to be followed. Besides control of the insect vector, use of antibiotics has temporarily suppressed the symptoms of HLB in diseased trees. Recent efforts to discover and screen existing as well as new compounds for their antibiotic and antimicrobial activities have identified some promising molecules for HLB control. There is an urgent need to find a sustainable solution to the HLB menace through chemical control of ACP populations and within HLB‐infected trees through the judicious use of labeled insecticides (existing and novel chemistries) and antibiotics in area‐wide management programs with due consideration to the insecticide resistance problem.
      PubDate: 2014-12-09T10:32:46.594044-05:
      DOI: 10.1002/ps.3957
       
  • Synthesis, Insecticidal Activities, and SAR Studies of Novel Anthranilic
           Diamides Containing Pyridylpyrazole‐4‐carboxamide
    • Authors: Kai Chen; Qi Liu, Jue‐Ping Ni, Hong‐Jun Zhu, Yu‐Feng Li, Qiang Wang
      Abstract: Background Anthranilic diamide insecticides containing pyridylpyrazole‐ 5‐carboxamide are extremely important in modern agriculture. New structurally modified compounds with high insecticidal activity were discovered by designing a series of novel pyridylpyrazole‐4‐carboxamides (9I‐9IV) and pyridylpyrazole‐4‐carboxamides (10I‐10IV), wherein the latter was designed by the cyclization of two amides. The structure‐activity relationship (SAR) between the two series was discussed in detail. Results Two series of novel anthranilic diamides containing pyridylpyrazole‐4‐carboxamide were synthesized and characterized via melting point, 1H NMR, 13C NMR, MS, and elemental analyses. The insecticidal activities of these compounds against Plutella xylostella were evaluated. At a concentration of 100 mg L−1, the compounds with unmodified amide moieties (9I‐9IV) exhibited much better larvicidal activities than the other derivative compounds (10I‐10IV). Most of the compounds 9I‐9IV showed over 90% larvicidal activity at 100 mg L−1. Furthermore, compounds 9IIIa, 9IIIc, 9IIId, and 9IVd displayed significant insecticidal activity at 10 mg L−1. DFT calculation was carried out to provide more information regarding SAR. Conclusion Thirty‐two new anthranlic diamides containing pyridylpyrazole‐4‐carboxamide were designed and obtained. SAR analysis and DFT calculation results revealed that the amide moiety had a very important effect on bioactivity. Thsi work provided information that could aid investigations on novel insecticides.
      PubDate: 2014-12-04T01:21:46.144354-05:
      DOI: 10.1002/ps.3954
       
  • Challenges in devising economic spray thresholds for a major pest of
           Australian canola, the redlegged earth mite (Halotydeus destructor)
    • Authors: Aston L. Arthur; Ary A. Hoffmann, Paul A. Umina
      Abstract: Background A key component for spray decision‐making in IPM programmes is the establishment of economic injury levels (EIL) and economic thresholds (ET). We aimed to establish an EIL for the redlegged earth mite (Halotydeus destructor Tucker) on canola. Results Complex interactions between mite numbers, feeding damage and plant recovery were found, highlighting the challenges in linking H. destructor numbers to yield. A guide of 10 mites per plant was established at the 1st true leaf stage; however simple relationships were not evident at other crop development stages, making it difficult to establish reliable EILs based on mite number. Yield was however strongly associated with plant damage and plant densities, reflecting the impact of mite feeding damage and indicating a plant‐based alternative for establishing thresholds for H. destructor. Drawing on data from multiple field trials, we show that plant densities below 30–40 per m2 could be used as a proxy for mite damage when reliable estimates of mite densities are not possible. Conclusion This plant‐based threshold provides a practical tool that avoids the difficulties of accurately estimating mite densities. The approach may be applicable to other situations where production conditions are unpredictable and interactions between pests and plant hosts are complex.
      PubDate: 2014-12-04T01:21:19.662236-05:
      DOI: 10.1002/ps.3952
       
  • Direct determination of methyl parathion insecticide in rice samples by
           headspace‐solid phase microextraction‐gas
           chromatography–mass spectrometry
    • Authors: Darlan Ferreira da Silva; Francisco Eduardo Paiva Silva, Fernanda Gabrielle S. Silva, Gilvanda Silva Nunes, Mihaela Badea
      Abstract: Background The organophosphorus insecticides, especially those based on methyl parathion as active principle, have been used extensively in the protection of rice in the Maranhão State, in the North‐East of Brazil. This paper describes the optimization of a solid phase microextraction (SPME) procedure in confined atmosphere (headspace, HS) for the determination of methyl parathion in rice organic samples, by gas chromatography with mass spectrometry detection (GC‐MS). Results The proposed HS‐SPME‐GC/MS method has shown to be appropriate for direct analysis of the insecticide in polished rice, with satisfactory results for the following parameters: linearity (correlation coefficient: 0.9985); sensitivity (LOD and LOQ of 0.026 and 0.078 µg.Kg−1, respectively); precision (CVs between 6.1 and 22.4%) and accuracy (recoveries varying from 73.2 to 90,0%). Although the efficiency of the proposed GC/MS do not differ statistically (p
      PubDate: 2014-12-04T01:20:04.486237-05:
      DOI: 10.1002/ps.3953
       
  • Spatial analysis of mass trapping: How close is close enough ?
    • Authors: DM Suckling; LD Stringer, JM Kean, PL Lo, V Bell, JTS Walker, AM Twidle, A Jiménez‐Pérez, AM El‐Sayed
      Abstract: Background The identification of new attractants can present opportunities for developing mass trapping, but standard screening methods are needed to expedite this. We have developed a simple approach based on quantifying trap interference in 4 × 4 trap arrays with different spacings. We discuss results from sex pheromones in Lepidoptera (lightbrown apple moth, Epiphyas postvittana), Diptera (apple leafcurling midge, Dasineura mali), and Homoptera (citrophilous mealybug, Pseudococcus calceolariae), compared with a kairomone for New Zealand flower thrips (Thrips obscuratus). Results The 25:1 ratio of catch in corner to centre traps observed at 750 D. mali traps/ha was still evident as ~5:1 at 16 traps/ha, suggesting trap interference even at such low trap densities. Trap competition for sex pheromone lures at close spacing (
      PubDate: 2014-12-03T02:04:34.308198-05:
      DOI: 10.1002/ps.3950
       
  • Chilo suppressalis and Sesamia inferens display different susceptibility
           responses to Cry1A insecticidal proteins
    • Authors: Bo Li; Yangyang Xu, Cao Han, Lanzhi Han, Maolin Hou, Yufa Peng
      Abstract: Background Chilo suppressalis and Sesamia inferens are important lepidopteran rice pests that occur concurrently in rice‐growing areas of China. The development of transgenic rice expressing Cry1A insecticidal proteins has provided a useful strategy for controlling these pests. Results This study evaluated the baseline susceptibilities of C. suppressalis and S. inferens to Cry1A, as well as their responses to selection with Cry1A. Wide geographical variation in susceptibility was observed across all field populations. Within a given population, the LC50 of both Cry1Ab and Cry1Ac against S. inferens was drastically higher than that of C. suppressalis. Large LC50 differences were detected between the two species for Cry1Ab in Poyang (74.6‐fold) population, while small differences were detected for Cry1Ac in Changsha (3.6‐fold) population. The Cry1Ac LC50 of C. suppressalis and S. inferens increased 8.4‐ and 4.4‐fold after 21 and 8 selection generations, respectively. Additionally, the estimated realized heritabilities (h2) of Cry1Ac tolerance were 0.11 in C. suppressalis and 0.292 in S. inferens. Conclusions S. inferens exhibited a significantly lower susceptibility and more rapidly evolved resistance to Cry1A compared to C. suppressalis. Therefore, S. inferens is more likely to evolve increased resistance, which threatens the sustainability of rice expressing Cry1A protein.
      PubDate: 2014-12-03T01:59:08.613214-05:
      DOI: 10.1002/ps.3948
       
  • Temperature‐dependent fecundity of overwintered Scirtothrips
           dorsalis (Thysanoptera: Thripidae) and its oviposition model with field
           validation
    • Authors: Seong Hyuk Kang; Joon‐Ho Lee, Dong‐Soon Kim
      Abstract: Background A population model can be a useful tool to understand population dynamics under various environmental factors, and can be useful for evaluating the efficacy of new management practices. This study was conducted to construct an oviposition model of overwintered Scirtothrips dorsalis as a part of its whole population model. Results Adult longevity decreased with increasing temperature and ranged from 44.7 d at 13 °C to 9.9 d at 33.0 °C. S. dorsalis showed a maximum fecundity of 52.6 eggs per female at 21 °C, which declined to 13.9 eggs per female at 33 °C. Egg development time decreased from 28.41 d at 13 °C to 5.14 d at 29 °C and 5.5 d at 33 °C. A oviposition model was developed based on three temperature‐dependent sub‐models: total fecundity, age‐specific oviposition rate and age‐specific survival rate model. Conclusion The oviposition model outputs well pursued the field occurrence patterns of S. dorsalis egg populations with a peak time discrepancy of 3 to 4 days. Our model should be useful for a population modeling of S. dorsalis in agricultural corps. Furthermore, the current model can be independently used for the timing of spraying against S. dorsalis in IPM programs of various crops.
      PubDate: 2014-12-03T01:58:59.147398-05:
      DOI: 10.1002/ps.3949
       
  • Predicting codling moth (Cydia pomonella) phenology in North Carolina
           based on temperature and improved generation turnover estimates
    • Authors: Thomas M. Chappell; George G. Kennedy, James F. Walgenbach
      Abstract: Background The codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), is major world‐wide pest of apples, pears and walnuts. A temperature‐driven phenological model of codling moth developed in Michigan has been utilized in North Carolina (NC) and other states for decades. Systematic inaccuracy of this model in predicting moth emergence in NC suggests that the relationship between emergence and temperature differs between the American midwest and southeast, or that additional factors may influence the system. Results A method was developed to optimize the estimation of generation turnover intervals. Emergence was modeled as a function of heat unit accumulation. Significant differences between emergence predictions based on the resultant model, and an existing model developed in Michigan, were found. Conclusion A new model of codling moth emergence incorporating improved estimates for generation turnover for North Carolina offers predictive improvement with practical importance to management. Differences between the emergence of susceptible and resistant moth populations were also investigated, leading to the suggestion that resistance to insecticides should be considered in future studies of emergence phenology.
      PubDate: 2014-12-02T08:14:22.247219-05:
      DOI: 10.1002/ps.3947
       
  • Abiotic Partitioning of Clothianidin Under Simulated Rice Field Conditions
    • Authors: Rebecca A. Mulligan; Sanjai J. Parikh, Ronald S. Tjeerdema
      Abstract: Background Clothianidin is registered for pre‐ and post‐flood application in California rice fields for control of the rice seed midge, Cricotopus sylvestris, and rice water weevil, Lissorhoptrus oryzophilus. The objective was to characterize air‐ and soil‐water partitioning of clothianidin under simulated California rice field conditions. Results Clothianidin was confirmed to be non‐volatile (from water) via the gas‐purge method, as no loss from the aqueous phase was observed at 22 and 37 °C; an upper limit KH value was calculated at 2.9 × 10−11 Pa m3 mol−1 (20 °C). Soil‐water partitioning was determined by the batch equilibrium method using four soils collected from rice fields in the Sacramento Valley, and sorption affinity (Kd), sorbent capacity, desorption and organic carbon‐normalized distribution (Koc) were determined. Values for pH, cation exchange capacity, and organic matter content ranged between 4.5 to 6.6, 5.9 to 37.9, and 1.25 to 1.97%, respectively. Log Koc values (22 and 37 °C) ranged between 2.6 to 2.7, while sorption capacity was low at 22 °C and further decreased at 37 °C. Hysteresis was observed in soils at both temperatures, suggesting that bound residues do not readily desorb. Conclusions Soil‐ and air‐water partitioning will not significantly reduce offsite transport of clothianidin from flooded rice fields via drainage.
      PubDate: 2014-12-01T09:19:27.505256-05:
      DOI: 10.1002/ps.3946
       
  • Engineering for disease resistance: persistent obstacles clouding tangible
           opportunities
    • Authors: Ewen Mullins
      Abstract: The accelerating pace of gene discovery coupled with novel plant breeding technologies provides tangible opportunities with which to engineer disease resistance into agricultural and horticultural crops. This is especially the case in regards to potato, wheat, apple and banana, which are afflicted with fungal and bacterial diseases that impact significantly on each crop's economic viability. Yet, public scepticism coupled with burdensome regulatory systems remain the two primary obstacles preventing the translation of research discoveries into cultivars of agronomic value. In this perspective review, the potential to address these issues is explained while specific opportunities arising from recent genomics‐based initiatives are highlighted as clear examples of what can be achieved in regards to developing disease resistance in crop species. There is an urgent need to tackle the challenge of agri‐chemical dependency in current crop production systems and while engineering for disease resistance is possible, it is not the sole solution and should not be proclaimed as so. Instead, all systems must be given due consideration with none dismissed in the absence of science‐based support; thereby ensuring future cropping systems have the necessary advantage over those pathogens that continue to inflict losses year after year.
      PubDate: 2014-10-29T06:20:59.92984-05:0
      DOI: 10.1002/ps.3930
       
  • Perspectives on Transgenic, Herbicide‐Resistant Crops in the USA
           Almost 20 Years after Introduction
    • Authors: Stephen O. Duke
      Abstract: Herbicide‐resistant crops have had profound impacts on weed management. Most of the impact has been by glyphosate‐resistant maize, cotton, soybean, and canola. Significant economic savings, yield increases, and more efficacious and simplified weed management resulted in widespread adoption of the technology. Initially, glyphosate‐resistant crops enabled significantly reduced tillage and reduced the environmental impact of weed management. Continuous use of glyphosate with glyphosate‐resistant crops over broad areas facilitated the evolution of glyphosate‐resistant weeds, which have resulted in increases in the use of tillage and other herbicides with glyphosate, reducing some of the initial environmental benefits of glyphosate‐resistant crops. Transgenic crops with resistance to auxinic herbicides, as well as to herbicides that inhibit acetolactate synthase, acetyl‐CoA carboxylase, and hydroxyphenylpyruvate dioxygenase, stacked with glyphosate and/or glufosinate resistance, will become available in the next few years. These technologies will provide additional weed management options for farmers, but will not have all of the positive impacts (reduced cost, simplified weed management, lowered environmental impact, and reduced tillage) that glyphosate‐resistant crops had initially. In the more distant future, other herbicide‐resistant crops (including non‐transgenic ones), herbicides with new modes of action, and technologies that are currently in their infancy (e.g., bioherbicides, sprayable herbicidal RNAi, and/or robotic weeding) may impact the role of transgenic, herbicide‐resistant crops in weed management.
      PubDate: 2014-07-23T03:39:08.764241-05:
      DOI: 10.1002/ps.3863
       
  • Phosphine resistance in Australian Cryptolestes species (Coleoptera:
           Laemophloeidae): Perspectives from mitochondrial DNA Cytochrome Oxidase I
           analysis
    • Authors: Wee Tek Tay; Stephen J. Beckett, Paul J. De Barro
      Abstract: Background The flat grain beetles (FGB) species Cryptolestes ferrugineus, C. pusillus, C. pusilloides, and C. turcicus are major stored products pests worldwide, of which the first three are present in Australia. C. ferrugineus is also a species with high phosphine resistance status in various countries. Morphological identification of Cryptolestes species is difficult and represents an additional barrier to effectively manage phosphine resistance in FGB. Result Mitochondrial DNA cytochrome oxidase I (mtDNA COI) gene characterisation enabled differentiation of the four major FGB pest species through direct sequence comparison, and enabled the development of a PCR‐RFLP method for rapid species differentiation. We detected two mtDNA haplotypes (Cunk‐01, 02) present at low frequencies with an average nucleotide divergence rate of 0.079 ± 0.011 (s.e.) from C. pusillus. This nucleotide divergence rate is similar to that between C. ferrugineus and C. pusilloides (0.088 ± 0.012). Male and female genitalia morphologies of the Cunk‐02 individuals indicated they were consistent with C. pusillus yet DNA sequence analyses suggested species‐level divergence. The mtDNA COI gene of phosphine bioassayed (at 720ppm; 1mg/L) lab‐reared F1 generation survivors supported the presence of strong phosphine resistance in C. ferrugineus, but unexpectedly also in C. pusilloides and C. pusillus F1 survivors. Conclusion We demonstrated the utility of molecular DNA techniques for differentiating closely related insect species, and its usefulness in assisting the management of pest insect species. The likely presence of a cryptic C. pusillus species in Australia and the possible development of strong phosphine resistance in Australian FGB pest species require further investigation.
      PubDate: 2014-04-21T04:29:26.937952-05:
      DOI: 10.1002/ps.3805
       
  • Dealing with transgene flow of crop protection traits from crops to their
           relatives
    • Authors: Jonathan Gressel
      Pages: 658 - 667
      Abstract: Genes regularly move within species, to/from crops, as well as to their con‐ specific progenitors, feral and weedy forms (‘vertical’ gene flow). Genes occasionally move to/from crops and their distantly related, hardly sexually interbreeding relatives, within a genus or among closely related genera (diagonal gene flow). Regulators have singled out transgene flow as an issue, yet non‐transgenic herbicide resistance traits pose equal problems, which cannot be mitigated. The risks are quite different from genes flowing to natural (wild) ecosystems versus ruderal and agroecosystems. Transgenic herbicide resistance poses a major risk if introgressed into weedy relatives; disease and insect resistance less so. Technologies have been proposed to contain genes within crops (chloroplast transformation, male sterility) that imperfectly prevent gene flow by pollen to the wild. Containment does not prevent related weeds from pollinating crops. Repeated backcrossing with weeds as pollen parents results in gene establishment in the weeds. Transgenic mitigation relies on coupling crop protection traits in a tandem construct with traits that lower the fitness of the related weeds. Mitigation traits can be morphological (dwarfing, no seed shatter) or chemical (sensitivity to a chemical used later in a rotation). Tandem mitigation traits are genetically linked and will move together. Mitigation traits can also be spread by inserting them in multicopy transposons which disperse faster than the crop protection genes in related weeds. Thus, there are gene flow risks mainly to weeds from some crop protection traits; risks that can and should be dealt with. © 2014 Society of Chemical Industry
      PubDate: 2014-08-15T05:36:04.894193-05:
      DOI: 10.1002/ps.3850
       
  • Nitric‐oxide‐mediated cell death is triggered by chitosan in
           Fusarium eumartii spores
    • Authors: María Cecilia Terrile; Andrea Yamila Mansilla, Liliana Albertengo, María Susana Rodríguez, Claudia Anahí Casalongué
      Pages: 668 - 674
      Abstract: BACKGROUND The genus Fusarium comprises a heterogeneous group of fungi important for agriculture. Fusarium solani f. sp. eumartii (F. eumartii), historically considered to be a fungal pathogen of potato, has also been associated with tomato disease. Currently, chitosan and its derivatives have been receiving more attention as environmentally friendly antimicrobial compounds in sustainable practices. The aim of the present work was to characterize downstream events associated with the mode of action of chitosan, including nitrosative reactive species, in order to identify new biomarkers of its cytotoxic action. RESULTS Data indicated that chitosan‐mediated nitric oxide (NO) production might lead to conidial death, concomitant with the strong reduction in fungal pathogenicity in tomato plants. Following chitosan applications, a notably dose‐dependent reduction in conidial viability was demonstrated in F. eumartii. Thereafter, the infectivity of chitosan‐treated spores was tested by a bioassay using tomato seedlings. CONCLUSION All these data highlight NO valuable properties as a quantitative and qualitative biomarker of cytotoxic action of chitosan in conidial cells. In addition, these findings place the chitosan assayed here as a fungicide with a high potential of application in sustainable horticultural practices. © 2014 Society of Chemical Industry
      PubDate: 2014-05-27T09:44:48.885146-05:
      DOI: 10.1002/ps.3814
       
  • Using next‐generation sequencing to detect mutations endowing
           resistance to pesticides: application to acetolactate‐synthase
           (ALS)‐based resistance in barnyard grass, a polyploid grass weed
    • Authors: Christophe Délye; Romain Causse, Véronique Gautier, Charles Poncet, Séverine Michel
      Pages: 675 - 685
      Abstract: BACKGROUND Next‐generation sequencing (NGS) technologies offer tremendous possibilities for accurate detection of mutations endowing pesticide resistance, yet their use for this purpose has not emerged in crop protection. This study aims at promoting NGS use for pesticide resistance diagnosis. It describes a simple procedure accessible to virtually any scientist and implementing freely accessible programs for the analysis of NGS data. RESULTS Three PCR amplicons encompassing seven codons of the acetolactate‐synthase gene crucial for herbicide resistance were sequenced using non‐quantified pools of crude DNA extracts from 40 plants in each of 28 field populations of barnyard grass, a polyploid weed. A total of 63 959 quality NGS sequence runs were obtained using the 454 technology. Three herbicide‐resistance‐endowing mutations (Pro‐197‐Ser, Pro‐197‐Leu and/or Trp‐574‐Leu) were identified in seven populations. The NGS results were confirmed by individual plant Sanger sequencing. CONCLUSION This work demonstrated the feasibility of NGS‐based detection of pesticide resistance, and the advantages of NGS compared with other molecular biology techniques for analysing large numbers of individuals. NGS‐based resistance diagnosis has the potential to play a substantial role in monitoring resistance, maintaining pesticide efficacy and optimising pesticide applications. © 2014 Society of Chemical Industry
      PubDate: 2014-05-27T10:54:05.463609-05:
      DOI: 10.1002/ps.3818
       
  • Plant strengtheners enhance parasitoid attraction to
           herbivore‐damaged cotton via qualitative and quantitative changes in
           induced volatiles
    • Authors: Islam S Sobhy; Matthias Erb, Ted CJ Turlings
      Pages: 686 - 693
      Abstract: BACKGROUND Herbivore‐damaged plants release a blend of volatile organic compounds (VOCs) that differs from undamaged plants. These induced changes are known to attract the natural enemies of the herbivores and therefore are expected to be important determinants of the effectiveness of biological control in agriculture. One way of boosting this phenomenon is the application of plant strengtheners, which has been shown to enhance parasitoid attraction in maize. It is unclear whether this is also the case for other important crops. RESULTS The plant strengtheners BTH [benzo (1,2,3) thiadiazole‐7‐carbothioic acid S‐methyl ester] and laminarin were applied to cotton plants, and the effects on volatile releases and the attraction of three hymenopteran parasitoids, Cotesia marginiventris, Campoletis sonorensis and Microplitis rufiventris, were studied. After treated and untreated plants were induced by real or simulated caterpillar feeding, it was found that BTH treatment increased the attraction of the parasitoids, whereas laminarin had no significant effect. BTH treatment selectively increased the release of two homoterpenes and reduced the emission of indole, the latter of which had been shown to interfere with parasitoid attraction in earlier studies. Canonical variate analyses of the data show that the parasitoid responses were dependent on the quality rather than the quantity of volatile emission in this tritrophic interaction. CONCLUSION Overall, these results strengthen the emerging paradigm that induction of plant defences with chemical elicitors such as BTH could provide a sustainable and environmentally friendly strategy for biological control of pests by enhancing the attractiveness of cultivated plants to natural enemies of insect herbivores. © 2014 Society of Chemical Industry
      PubDate: 2014-06-03T09:45:20.920793-05:
      DOI: 10.1002/ps.3821
       
  • Design, synthesis and insecticidal activity of novel
           1,1‐dichloropropene derivatives
    • Authors: Jun Li; Zhen‐Yu Wang, Qiong‐You Wu, Guang‐Fu Yang
      Pages: 694 - 700
      Abstract: BACKGROUND Pyridalyl is a highly active insecticide against lepidopterous larvae, with a novel chemical structure not related to any other existing insecticide. To discover new pyridalyl analogues with high activity against resistant pests, a series of 1,1‐dichloropropene derivatives bearing structurally diverse substituted heterocycle rings in place of the pyridine ring of pyridalyl were designed and synthesised. RESULTS All of the title compounds were confirmed by 1H NMR, 13C NMR and high‐resolution mass spectra. Two representative compounds (Ic and IIa) were further characterised by X‐ray diffraction analysis. In addition, bioassays showed that most of the newly synthesised compounds displayed good insecticidal activity against Prodenia litura. Further determination of LD50 values and field trials identified compound IIa as the most promising candidate, which produced a much better 14 day control effect against diamondback moths and longer duration of efficacy than pyridalyl, indicating its potential for further development as a new insecticide for the control of lepidopteran insects. CONCLUSION Compound IIa has great potential for further development as a new insecticide for the control of lepidopteran insects. © 2014 Society of Chemical Industry
      PubDate: 2014-06-05T07:35:09.882866-05:
      DOI: 10.1002/ps.3827
       
  • Structure–activity relationship studies of the phytotoxic properties
           of the diterpenic moiety of breviones
    • Authors: Ceferino Carrera; Nuria Chinchilla, Frank R Fronczek, Juan CG Galindo, Francisco A Macías
      Pages: 701 - 711
      Abstract: BACKGROUND Brevianes are a family of bioactive meroterpenoids originally described in fungi of the family Penicillium. These compounds have attracted a great deal of interest not only because of their unusual skeleton, suggesting a mixed mevalonate and polyketide biogenetic pathway, and their unusual oxa‐spiro ring fused to an α‐pyrone, but also because of the bioactivities shown by many members of this family. RESULTS During the course of a project aimed at the total synthesis of natural breviones A to E, the authors were able to synthesise the diterpenic moiety of brevianes and abeo‐brevianes. As a result, a collection of 25 compounds were synthesised and tested for bioactivity by two different bioassays. The bioassays used were etiolated wheat coleoptiles (Triticum aestivum) and seedlings in petri dishes. The plant species tested in the seedling bioassay were the commercial dicots lettuce and cress and the monocot weeds Echinochloa crus‐galli and Lolium rigidum. CONCLUSIONS The results clearly show that expanded phenanthrene‐like compounds corresponding to the diterpenic moiety of abeo‐brevianes are more selective towards E. crus‐galli in comparison with L. rigidum. Such selectivity can reach up to one order of magnitude (200‐fold) and makes some of the compounds good candidates as leads for the development of more specific herbicides. [[ArtCopyrightmsg]]
      PubDate: 2014-06-11T08:06:24.328344-05:
      DOI: 10.1002/ps.3831
       
  • Insecticide resistance and cross‐resistance development in Colorado
           potato beetle Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae)
           populations in Canada 2008–2011
    • Authors: Ian M Scott; Jeff H Tolman, Dale C MacArthur
      Pages: 712 - 721
      Abstract: BACKGROUND A survey of insecticide resistance in over 150 Canadian populations of Colorado potato beetle was completed between 2008 and 2011. Three neonicotinoid and two anthranilic diamide insecticides were tested at a discriminating concentration (DC) with second‐instar larvae in a leaf‐disc bioassay. RESULTS The mean mortality for the imidacloprid (Admire) DC was 46–67% between 2008 and 2011 respectively. Over the 4 years, 10–46% and 26–40% of the populations were classified as resistant or showed reduced susceptibility to imidacloprid. The mean mortality for thiamethoxam (Actara) and clothianidin (Poncho/Titan) ranged from 56–76% in 2008 to 81–84% in 2010 for each insecticide respectively, indicating continuous susceptibility to clothianidin but reduced susceptibility to thiamethoxam. In 2008 and 2009, susceptibility to chlorantraniliprole (Coragen) was observed in 85% of populations. Similarly, cyantraniliprole (Cyazypyr) affected 93% of the 2009 and 74% of the 2010 populations. There was a significant (P < 0.05) and high positive correlation (R = 0.4–0.84) between the three neonicotinoids, indicating the potential for cross‐resistance. CONCLUSIONS The trend observed in decreasing susceptibility for thiamethoxam and clothianidin will continue unless resistance management practices are followed. © 2014 Her Majesty the Queen in Right of Canada Pest Management Science © 2014 Society of Chemical Industry
      PubDate: 2014-06-24T00:58:26.950133-05:
      DOI: 10.1002/ps.3833
       
  • Impact of Bacillus amyloliquefaciens S13‐3 on control of bacterial
           wilt and powdery mildew in tomato
    • Authors: Shoko Yamamoto; Soma Shiraishi, Yumi Kawagoe, Mai Mochizuki, Shunji Suzuki
      Pages: 722 - 727
      Abstract: BACKGROUND Biological control is a non‐hazardous technique to control plant diseases. Researchers have explored microorganisms that show high plant‐disease control efficiency for use as biological control agents. RESULTS A single soil application of Bacillus amyloliquefaciens strain S13‐3 suppressed tomato bacterial wilt caused by Ralstonia solanacearum, a soilborne bacterial pathogen, through production of antibiotics augmented possibly by induction of systemic acquired resistance. Soil application also controlled tomato powdery mildew disease through induction of systemic acquired resistance. CONCLUSION S13‐3 showing bifunctional activity with a single application to soil may be an innovative biological control agent against bacterial wilt and powdery mildew in tomato. © 2014 Society of Chemical Industry
      PubDate: 2014-06-27T07:35:09.577814-05:
      DOI: 10.1002/ps.3837
       
  • Polyenylcyclopropane carboxylic esters with high insecticidal activity
    • Authors: Claudia Ferroni; Lucio Bassetti, Valerio Borzatta, Elisa Capparella, Carlotta Gobbi, Alberto Guerrini, Greta Varchi
      Pages: 728 - 736
      Abstract: BACKGROUND Pyrethroids are synthetic derivatives of naturally occurring pyrethrum. These molecules are widely used in agriculture for ant, fly and mosquito control and for lawn and garden care. Pyrethroids are the optically active esters of 2,2‐dimethyl‐3‐(2‐methylpropenyl)‐cyclopropane carboxylic acid, also known as chrysanthemic acid. However, their intense use has resulted in the development of resistance in many insect species. Herein, specific structural modifications of the pyrethroid scaffold and their effect on insecticidal activity, especially on resistant pests strains, are reported. RESULTS The exposure to (1R)‐trans‐(E/Z)‐2,3,5,6‐tetrafluorobenzyl‐3‐(buta‐1,3‐dienyl)‐2,2‐dimethyl cyclopropanecarboxylate and its diastereomers produced 100% mortality in yellow fever mosquitoes (Aedes aegypti), house mosquitoes (Culex quinquefasciatus) and houseflies (Musca domestica). Moreover, this compound provided complete knockdown within 15 min of exposure against cockroaches (Blattella germanica) and maintained an excellent knockdown activity at 10 days after treatment. CONCLUSION Novel pyrethroid derivatives obtained from 2,2‐dimethyl‐3‐(2‐methylpropenyl)‐cyclopropanecarboxylic acid are described. These derivatives display high insecticidal activity, a wide spectrum of action and no toxicity towards mammalians. The proposed synthetic procedures are highly efficient and inexpensive, and therefore suitable for industrial scale‐up. © 2014 Society of Chemical Industry
      PubDate: 2014-07-03T03:39:42.736136-05:
      DOI: 10.1002/ps.3842
       
  • Toxicity of hiba oil constituents and spray formulations to American house
           dust mites and copra mites
    • Authors: Jun‐Ran Kim; Haribalan Perumalsamy, Min Jung Kwon, Se Um Chae, Young‐Joon Ahn
      Pages: 737 - 743
      Abstract: BACKGROUND Dermatophagoides farinae and Tyrophagus putrescentiae are recognised as an important source of allergens. An assessment was made of the toxicity of hiba, Thujopsis dolabrata var. hondai, oil and 13 organic compounds and the control efficacy of four experimental spray formulations containing the oil (5–30 g L−1 spray) against both mite species. RESULTS In a contact + fumigant mortality bioassay, (−)‐thujopsene was the most toxic constituent against D. farinae and T. putrescentiae (24 h LC50 9.82 and 10.92 µg cm−2), and the toxicity of the compound was nearly identical to that of benzyl benzoate (9.33 and 10.14 µg cm−2). The toxicity was more pronounced in carvacrol, (+)‐terpinen‐4‐ol, β‐thujaplicin, (−)‐terpinen‐4‐ol, cedrol and α‐terpineol (LC50 12.05–15.20 and 12.74–16.48 µg cm−2) than in N,N‐diethyl‐3‐methylbenzamide (LC50 35.53 and 38.42 µg cm−2) against both mite species. The hiba oil 30 g L−1 spray and commercial permethrin (cis:trans 25:75) 2.5 g L−1 spray treatment resulted in 100 and 11% mortality against the two mite species respectively. In vapour‐phase mortality tests, the two compounds were consistently more toxic in closed versus open containers, indicating that toxicity was achieved mainly through the action of vapour. CONCLUSION Reasonable mite control in indoor environments can be achieved by a spray formulation containing the 30 g L−1 hiba oil as a potential contact‐action fumigant. © 2014 Society of Chemical Industry
      PubDate: 2014-07-04T06:24:37.849803-05:
      DOI: 10.1002/ps.3843
       
  • Estimating the development of the fennel aphid, Hyadaphis foeniculi
           (Passerini) (Hemiptera: Aphiididae), using non‐linear models
    • Authors: José B Malaquias; Francisco S Ramalho, Aline CS Lira, Flávia Q Oliveira, Francisco S Fernandes, José C Zanuncio, Wesley AC Godoy
      Pages: 744 - 751
      Abstract: BACKGROUND Non‐linear models making it possible to predict agricultural pest outbreaks and optimise control tactics are of primary importance for integrated pest management. The development period for immature stages of the fennel aphid Hyadaphis foeniculi (Passerini) (Hemiptera: Aphididae) at constant temperatures was modelled in order to determine mathematical functions for simulating the aphid's development. Non‐linear models were used to describe the relationship between temperature and development rates of H. foeniculi subjected to constant temperatures. RESULTS The models used were found to be good fits for estimating H. foeniculi development rates as a function of temperature, with the exception of the Davidson model. The development time of H. foeniculi nymphs ranged from 2.73 days (first instar) to 6.18 days (fourth instar) at 15 °C, from 2.57 days (first instar) to 4.52 days (fourth instar) at 20 °C and from 1.53 days (first instar) to 2.05 days (fourth instar) at 28 °C. CONCLUSION These models provide important tools for better elucidation of the relationship between temperature and development rates in H. foeniculi. The results could be used for predicting the occurrence of the various immature stages of H. foeniculi in the fennel crop in Brazil, making it possible to predict more accurately the best periods for implementing pest control. © 2014 Society of Chemical Industry
      PubDate: 2014-07-10T06:00:22.685458-05:
      DOI: 10.1002/ps.3845
       
  • Laboratory and field assessment of cyantraniliprole relative to existing
           fly baits
    • Authors: Amy C Murillo; Alec C Gerry, Nicola T Gallagher, Nyles G Peterson, Bradley A Mullens
      Pages: 752 - 758
      Abstract: BACKGROUND Toxic fly baits are commonly used for fly control in California animal operations. However, resistance development has been a problem. Comprehensive laboratory and field studies were conducted to test commercial baits (imidacloprid, methomyl, dinotefuran, spinosad) and one novel cyantraniliprole bait. A susceptible Musca domestica strain was compared with wild‐type M. domestica and Fannia canicularis strains in the laboratory using choice/no‐choice tests. Field visitation to baits and both short‐ and longer‐term mortality were documented. RESULTS Susceptible Musca suffered high mortality with all baits after 3 days of choice and no‐choice tests. Wild‐type Musca mortality was more variable and higher in no‐choice relative to choice tests. Fannia were most susceptible to spinosad > dinotefuran = cyantraniliprole > methomyl = imidacloprid. Field Musca were most attracted to spinosad > cyantraniliprole > dinotefuran > sugar > methomyl > imidacloprid. Delayed mortality from bait‐fed field flies (captured and held with untreated food and water for 3 days) was ranked spinosad = cyantraniliprole > dinotefuran = methomyl > imidacloprid > sugar. CONCLUSION Behavioral resistance of M. domestica to imidacloprid and methomyl persists. Spinosad and cyantraniliprole baits (delayed mortality) performed best. Speed of action may be a factor in use and misuse of baits. © 2014 Society of Chemical Industry
      PubDate: 2014-07-15T10:22:23.135631-05:
      DOI: 10.1002/ps.3847
       
  • Biofumigation with Brassica juncea, Raphanus sativus and Eruca sativa for
           the management of field populations of the potato cyst nematode Globodera
           pallida
    • Authors: Bruno M Ngala; Patrick PJ Haydock, Simon Woods, Matthew A Back
      Pages: 759 - 769
      Abstract: BACKGROUND The viability of potato cyst nematode (PCN) populations (Globodera pallida) was evaluated in three field experiments using Brassica juncea, Raphanus sativus and Eruca sativa amendments. These species were summer cultivated and autumn incorporated in experiment 1; in experiment 2, overwintered brassicaceous cover crops were spring incorporated. Experiment 3 involved determination of effects of metconazole application on biomass/glucosinolate production by B. juncea and R. sativus and on PCN pre‐ and post‐incorporation. Glucosinolate contents were determined before incorporation. Following cover crop incorporation, field plots were planted with susceptible potatoes to evaluate the biofumigation effects on PCN reproduction. RESULTS In experiment 1, PCN population post‐potato harvest was reduced (P = 0.03) in B. juncea‐treated plots, while R. sativus prevented further multiplication, but in experiment 2 there were no significant effects on PCN reproduction. In experiment 3, B. juncea or R. sativus either untreated or treated with metconazole reduced PCN populations. Glucosinolate concentrations varied significantly between different plant regions and cultivation seasons. Metconazole application increased the sinigrin concentration in B. juncea tissues. Glucosinolate concentrations correlated positively with PCN mortality for summer‐cultivated brassicaceous plants. CONCLUSION The results demonstrated that B. juncea and R. sativus green manures can play an important role in PCN management, particularly if included in an integrated pest management scheme. © 2014 Society of Chemical Industry
      PubDate: 2014-07-23T08:41:19.800531-05:
      DOI: 10.1002/ps.3849
       
  • Induced resistance by oxidative shifts in pigeonpea (Cajanus cajan L.)
           following Helicoverpa armigera (Hübner) herbivory
    • Authors: Rimaljeet Kaur; Anil K Gupta, Gaurav K Taggar
      Pages: 770 - 782
      Abstract: BACKGROUND Oxidative responses in leaves, developing seeds and the pod wall of nine pigeonpea genotypes were investigated against Helicoverpa armigera feeding. Out of nine genotypes, four were moderately resistant, three were intermediate and two were moderately susceptible genotypes. RESULTS A significant shift in the oxidative status of pigeonpea following herbivory was depicted by the upregulation of diamine oxidase (DAO), polyamine oxidase (PAO) and lipoxygenase 2 (LOX 2) activities. Polyphenol oxidase (PPO) activity was significantly higher in the infested pod wall and leaves of moderately resistant genotypes than in those of moderately susceptible genotypes. H. armigera infestation markedly enhanced phenylalanine ammonia lyase (PAL) and tyrosine ammonia lyase (TAL) activities in wounded tissues. The decline in ascorbate peroxidase (APX) activity and ascorbate content was lower in moderately resistant genotypes than in moderately susceptible genotypes. A significant decrease in LOX 3 activity was also observed in the infested pod wall of moderately resistant and intermediate genotypes. A lower malondialdehyde (MDA) content and higher proline content of the infested pod wall and developing seeds was observed. Higher activities of PPO, PAL and proline content in leaves of uninfested moderately resistant genotypes could either be an unrelated observation or alternatively could help in identifying H. armigera‐resistant genotypes. CONCLUSION The increase in activities of PPO, DAO, PAO, PAL and TAL and higher proline and lower MDA content upon herbivory suggested their integrated contribution in providing resistance to pigeonpea against H. armigera. © 2014 Society of Chemical Industry
      PubDate: 2014-07-25T08:47:20.138845-05:
      DOI: 10.1002/ps.3851
       
  • Protection of winter wheat against orange wheat blossom midge,
           Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae): efficacy of
           insecticides and cultivar resistance
    • Authors: Sandrine Chavalle; Florence Censier, Gilles San Martin y Gomez, Michel De Proft
      Pages: 783 - 790
      Abstract: BACKGROUND In 2012 and 2013, Sitodiplosis mosellana (Géhin) flights occurred during the susceptible phase of wheat development in Belgium. The protection against this midge afforded by various insecticides was assessed in infested fields on four winter wheat cultivars (susceptible or resistant, and early or late heading). RESULTS The insecticides sprayed at the right time reduced the number of larvae in the ears by 44–96%, depending on the product. For Julius, the cultivar (cv.) most exposed to S. mosellana in 2013, the mean yield gain resulting from insecticide use was 1558 kg ha−1 (18%). In the same year, insecticide use resulted in a yield gain of 780 kg ha−1 (8%) for the cv. Lear, in spite of its resistance to this pest. The link between yield and number of larvae counted in the ears was a logarithmic relationship, suggesting an important reduction in yield, caused either by the damage inflicted by young larvae that died at the start of their development or by the activation of costly reactions in plants. CONCLUSION The study showed that, in cases of severe attack, the timely application of insecticide treatments can protect wheat against S. mosellana, and that even resistant cultivars can benefit from these treatments. © 2014 Society of Chemical Industry
      PubDate: 2014-08-06T08:57:45.284253-05:
      DOI: 10.1002/ps.3855
       
 
 
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