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  Subjects -> BIOLOGY (Total: 2992 journals)
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BIOLOGY (1423 journals)                  1 2 3 4 5 6 7 8 | Last

Showing 1 - 200 of 1720 Journals sorted alphabetically
AAPS Journal     Hybrid Journal   (Followers: 20)
Achievements in the Life Sciences     Open Access   (Followers: 4)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 21)
Acta Biologica Colombiana     Open Access   (Followers: 7)
Acta Biologica Hungarica     Full-text available via subscription   (Followers: 4)
Acta Biologica Sibirica     Open Access  
Acta Biomaterialia     Hybrid Journal   (Followers: 25)
Acta Biotheoretica     Hybrid Journal   (Followers: 5)
Acta Chiropterologica     Full-text available via subscription   (Followers: 6)
acta ethologica     Hybrid Journal   (Followers: 4)
Acta Limnologica Brasiliensia     Open Access   (Followers: 3)
Acta Médica Costarricense     Open Access   (Followers: 2)
Acta Musei Silesiae, Scientiae Naturales : The Journal of Silesian Museum in Opava     Open Access  
Acta Parasitologica     Hybrid Journal   (Followers: 9)
Acta Scientiarum. Biological Sciences     Open Access   (Followers: 2)
Acta Scientifica Naturalis     Open Access   (Followers: 2)
Actualidades Biológicas     Open Access   (Followers: 1)
Advanced Health Care Technologies     Open Access   (Followers: 4)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 3)
Advances in Bioinformatics     Open Access   (Followers: 18)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4)
Advances in Biology     Open Access   (Followers: 8)
Advances in Biosensors and Bioelectronics     Open Access   (Followers: 6)
Advances in Cell Biology     Open Access   (Followers: 23)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 12)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 11)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 5)
Advances in Ecological Research     Full-text available via subscription   (Followers: 41)
Advances in Ecology     Open Access   (Followers: 16)
Advances in Environmental Sciences - International Journal of the Bioflux Society     Open Access   (Followers: 20)
Advances in Enzyme Research     Open Access   (Followers: 9)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 7)
Advances in Genome Biology     Full-text available via subscription   (Followers: 11)
Advances in High Energy Physics     Open Access   (Followers: 19)
Advances in Human Biology     Open Access   (Followers: 1)
Advances in Life Science and Technology     Open Access   (Followers: 14)
Advances in Life Sciences     Open Access   (Followers: 4)
Advances in Marine Biology     Full-text available via subscription   (Followers: 16)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 22)
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3)
Advances in Regenerative Biology     Open Access   (Followers: 1)
Advances in Structural Biology     Full-text available via subscription   (Followers: 8)
Advances in Virus Research     Full-text available via subscription   (Followers: 5)
African Journal of Range & Forage Science     Hybrid Journal   (Followers: 6)
AFRREV STECH : An International Journal of Science and Technology     Open Access   (Followers: 1)
Ageing Research Reviews     Hybrid Journal   (Followers: 8)
Aging Cell     Open Access   (Followers: 10)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Agrokreatif Jurnal Ilmiah Pengabdian kepada Masyarakat     Open Access  
AJP Cell Physiology     Full-text available via subscription   (Followers: 13)
AJP Endocrinology and Metabolism     Full-text available via subscription   (Followers: 22)
AJP Lung Cellular and Molecular Physiology     Full-text available via subscription   (Followers: 3)
Al-Kauniyah : Jurnal Biologi     Open Access  
Alasbimn Journal     Open Access   (Followers: 1)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Biology Teacher     Full-text available via subscription   (Followers: 12)
American Fern Journal     Full-text available via subscription   (Followers: 1)
American Journal of Agricultural and Biological Sciences     Open Access   (Followers: 10)
American Journal of Bioethics     Hybrid Journal   (Followers: 10)
American Journal of Biostatistics     Open Access   (Followers: 9)
American Journal of Human Biology     Hybrid Journal   (Followers: 12)
American Journal of Medical and Biological Research     Open Access   (Followers: 5)
American Journal of Plant Sciences     Open Access   (Followers: 19)
American Journal of Primatology     Hybrid Journal   (Followers: 15)
American Malacological Bulletin     Full-text available via subscription   (Followers: 3)
American Naturalist     Full-text available via subscription   (Followers: 65)
Amphibia-Reptilia     Hybrid Journal   (Followers: 6)
Anaerobe     Hybrid Journal   (Followers: 4)
Analytical Methods     Full-text available via subscription   (Followers: 7)
Anatomical Science International     Hybrid Journal   (Followers: 2)
Animal Cells and Systems     Hybrid Journal   (Followers: 4)
Annales de Limnologie - International Journal of Limnology     Hybrid Journal   (Followers: 1)
Annales françaises d'Oto-rhino-laryngologie et de Pathologie Cervico-faciale     Full-text available via subscription   (Followers: 3)
Annales Henri Poincaré     Hybrid Journal   (Followers: 3)
Annales UMCS, Biologia     Open Access   (Followers: 1)
Annals of Applied Biology     Hybrid Journal   (Followers: 8)
Annals of Biomedical Engineering     Hybrid Journal   (Followers: 18)
Annals of Human Biology     Hybrid Journal   (Followers: 4)
Annual Review of Biomedical Engineering     Full-text available via subscription   (Followers: 17)
Annual Review of Biophysics     Full-text available via subscription   (Followers: 25)
Annual Review of Cancer Biology     Full-text available via subscription  
Annual Review of Cell and Developmental Biology     Full-text available via subscription   (Followers: 38)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 14)
Annual Review of Genomics and Human Genetics     Full-text available via subscription   (Followers: 19)
Annual Review of Phytopathology     Full-text available via subscription   (Followers: 10)
Anthropological Review     Open Access   (Followers: 25)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antibiotics     Open Access   (Followers: 8)
Antioxidants     Open Access   (Followers: 4)
Antioxidants & Redox Signaling     Hybrid Journal   (Followers: 8)
Antonie van Leeuwenhoek     Hybrid Journal   (Followers: 5)
Anzeiger für Schädlingskunde     Hybrid Journal   (Followers: 1)
Apidologie     Hybrid Journal   (Followers: 4)
Apmis     Hybrid Journal   (Followers: 1)
APOPTOSIS     Hybrid Journal   (Followers: 8)
Applied Bionics and Biomechanics     Open Access   (Followers: 8)
Applied Vegetation Science     Full-text available via subscription   (Followers: 9)
Aquaculture Environment Interactions     Open Access   (Followers: 2)
Aquaculture International     Hybrid Journal   (Followers: 22)
Aquaculture Reports     Open Access   (Followers: 3)
Aquaculture, Aquarium, Conservation & Legislation - International Journal of the Bioflux Society     Open Access   (Followers: 6)
Aquatic Biology     Open Access   (Followers: 4)
Aquatic Ecology     Hybrid Journal   (Followers: 30)
Aquatic Ecosystem Health & Management     Hybrid Journal   (Followers: 13)
Aquatic Science and Technology     Open Access   (Followers: 3)
Aquatic Toxicology     Hybrid Journal   (Followers: 19)
Archaea     Open Access   (Followers: 3)
Archiv für Molluskenkunde: International Journal of Malacology     Full-text available via subscription   (Followers: 3)
Archives of Biomedical Sciences     Open Access   (Followers: 7)
Archives of Microbiology     Hybrid Journal   (Followers: 8)
Archives of Natural History     Hybrid Journal   (Followers: 7)
Archives of Oral Biology     Hybrid Journal   (Followers: 2)
Archives of Virology     Hybrid Journal   (Followers: 5)
Archivum Immunologiae et Therapiae Experimentalis     Hybrid Journal   (Followers: 2)
Arid Ecosystems     Hybrid Journal   (Followers: 3)
Arquivos do Instituto Biológico     Open Access   (Followers: 1)
Arquivos do Museu Dinâmico Interdisciplinar     Open Access  
Arthropod Structure & Development     Hybrid Journal   (Followers: 2)
Arthropods     Open Access   (Followers: 1)
Artificial DNA: PNA & XNA     Hybrid Journal   (Followers: 2)
Artificial Photosynthesis     Open Access   (Followers: 1)
Asian Bioethics Review     Full-text available via subscription   (Followers: 1)
Asian Journal of Biodiversity     Open Access   (Followers: 5)
Asian Journal of Biological Sciences     Open Access   (Followers: 3)
Asian Journal of Cell Biology     Open Access   (Followers: 5)
Asian Journal of Developmental Biology     Open Access   (Followers: 2)
Asian Journal of Medical and Biological Research     Open Access   (Followers: 2)
Asian Journal of Nematology     Open Access   (Followers: 3)
Asian Journal of Poultry Science     Open Access   (Followers: 4)
Australian Life Scientist     Full-text available via subscription   (Followers: 2)
Australian Mammalogy     Hybrid Journal   (Followers: 5)
Autophagy     Hybrid Journal   (Followers: 2)
Avian Biology Research     Full-text available via subscription   (Followers: 4)
Avian Conservation and Ecology     Open Access   (Followers: 10)
Bacteriology Journal     Open Access   (Followers: 2)
Bacteriophage     Full-text available via subscription   (Followers: 3)
Bangladesh Journal of Bioethics     Open Access  
Bangladesh Journal of Plant Taxonomy     Open Access  
Bangladesh Journal of Scientific Research     Open Access   (Followers: 1)
Berita Biologi     Open Access   (Followers: 1)
Between the Species     Open Access   (Followers: 1)
Bio Tribune Magazine     Hybrid Journal  
BIO Web of Conferences     Open Access  
BIO-Complexity     Open Access  
Bio-Grafía. Escritos sobre la Biología y su enseñanza     Open Access  
Bioanalytical Reviews     Hybrid Journal   (Followers: 2)
Biocatalysis and Biotransformation     Hybrid Journal   (Followers: 6)
Biochemistry and Cell Biology     Hybrid Journal   (Followers: 14)
Biochimie     Hybrid Journal   (Followers: 7)
BioControl     Hybrid Journal   (Followers: 5)
Biocontrol Science and Technology     Hybrid Journal   (Followers: 5)
Biodemography and Social Biology     Hybrid Journal   (Followers: 1)
Biodiversidad Colombia     Open Access  
Biodiversity : Research and Conservation     Open Access   (Followers: 26)
Biodiversity and Natural History     Open Access   (Followers: 5)
Biodiversity Data Journal     Open Access   (Followers: 3)
Biodiversity Informatics     Open Access  
Bioedukasi : Jurnal Pendidikan Biologi FKIP UM Metro     Open Access  
Bioeksperimen : Jurnal Penelitian Biologi     Open Access  
Bioelectrochemistry     Hybrid Journal   (Followers: 2)
Bioelectromagnetics     Hybrid Journal   (Followers: 1)
Bioenergy Research     Hybrid Journal   (Followers: 2)
Bioengineering and Bioscience     Open Access   (Followers: 1)
BioEssays     Hybrid Journal   (Followers: 10)
Bioethics     Hybrid Journal   (Followers: 14)
BioéthiqueOnline     Open Access  
Biofabrication     Hybrid Journal   (Followers: 3)
Biogeosciences (BG)     Open Access   (Followers: 10)
Biogeosciences Discussions (BGD)     Open Access   (Followers: 1)
Bioinformatics     Hybrid Journal   (Followers: 293)
Bioinformatics and Biology Insights     Open Access   (Followers: 15)
Bioinspiration & Biomimetics     Hybrid Journal   (Followers: 6)
Biointerphases     Open Access   (Followers: 1)
Biojournal of Science and Technology     Open Access  
Biologia     Hybrid Journal  
Biologia on-line : Revista de divulgació de la Facultat de Biologia     Open Access  
Biological Bulletin     Partially Free   (Followers: 4)
Biological Control     Hybrid Journal   (Followers: 5)
Biological Invasions     Hybrid Journal   (Followers: 16)
Biological Journal of the Linnean Society     Hybrid Journal   (Followers: 15)
Biological Letters     Open Access   (Followers: 4)
Biological Procedures Online     Open Access  
Biological Psychiatry     Hybrid Journal   (Followers: 42)
Biological Psychology     Hybrid Journal   (Followers: 6)
Biological Research     Open Access  
Biological Rhythm Research     Hybrid Journal   (Followers: 2)
Biological Theory     Hybrid Journal   (Followers: 1)
Biological Trace Element Research     Hybrid Journal  
Biologicals     Full-text available via subscription   (Followers: 9)
Biologics: Targets & Therapy     Open Access   (Followers: 1)
Biologie Aujourd'hui     Full-text available via subscription  
Biologie in Unserer Zeit (Biuz)     Hybrid Journal   (Followers: 42)
Biologija     Open Access  
Biology     Open Access   (Followers: 5)
Biology and Philosophy     Hybrid Journal   (Followers: 16)
Biology Bulletin     Hybrid Journal   (Followers: 1)
Biology Bulletin Reviews     Hybrid Journal  
Biology Direct     Open Access   (Followers: 7)
Biology Letters     Full-text available via subscription   (Followers: 35)

        1 2 3 4 5 6 7 8 | Last

Journal Cover Annals of Applied Biology
  [SJR: 0.816]   [H-I: 56]   [8 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0003-4746 - ISSN (Online) 1744-7348
   Published by John Wiley and Sons Homepage  [1576 journals]
  • The role of invertebrates in seedling establishment in a heterocarpic
           plant, Atriplex sagittata
    • Authors: A. Honek; Z. Martinkova, S. Koprdova, P. Saska
      Abstract: Seed heteromorphism is a marked character of many Chenopodioideae (Amaranthaceae). Seed morphs differ in dormancy, germination and seedling biology, but differences in their predation have not yet been studied. Atriplex sagittata produces small black dormant and large brown non-dormant seeds. In this study, the timing of seed release and seedling establishment were ascertained, and their consumption by invertebrates (carabids, isopods and slugs) was studied. Seeds dispersed in the autumn passed the winter on the ground surface, protected from invertebrate predation by low temperatures. In the following vegetative season, ungerminated black seeds exposed to predation on ground surface were preferred by a large carabid species, Pseudoophonus rufipes. Some black and all brown seeds escaped predation by germinating in early spring. The seedlings were little endangered by carabids and isopods but were preferred by an invasive slug, Arion vulgaris, the feeding of which can exterminate seedlings at places in which slugs are abundant. Invertebrate predation is important factor of seed and seedling mortality of A. sagittata and seed heteromorphism modifies its intensity and timing.
      PubDate: 2017-07-10T21:35:46.702817-05:
      DOI: 10.1111/aab.12372
       
  • Recent advances and prospects in Prunus virology
    • Authors: M. Rubio; P. Martínez-Gómez, A. Marais, J.A. Sánchez-Navarro, V. Pallás, T. Candresse
      Abstract: The stone fruit genus Prunus, within the family Rosaceae, comprises more than 230 species, some of which have great importance or value as ornamental or fruit crops. Prunus are affected by numerous viruses and viroids linked to the vegetative propagation practices in many of the cultivated species. To date, 44 viruses and three viroids have been described in the 9 main cultivated Prunus species. Seven of these viruses and one viroid have been identified in Prunus hosts within the last 5 years. This work addresses recent advances and prospects in the study of viruses and viroids affecting Prunus species, mostly concerning the detection and characterisation of the agents involved, pathogenesis analysis and the search for new control tools. New sequencing technologies are quickly reshaping the way we can identify and characterise new plant viruses and isolates. Specific efforts aimed at virus identification or data mining of high-throughput sequencing data generated for plant genomics-oriented purposes can efficiently reveal the presence of known or novel viruses. These technologies have also been used to gain a deeper knowledge of the pathogenesis mechanisms at the gene and miRNA expression level that underlie the interactions between Prunus spp. and their main viruses and viroids. New biotechnological control tools include the transfer of resistance by grafting, the use of new sources of resistance and the development of gene silencing strategies using genetic transformation. In addition, the application of next generation sequencing and genome editing techniques will contribute to improving our knowledge of virus–host interactions and the mechanisms of resistance. This should be of great interest in the search to obtain new Prunus cultivars capable of dealing both with known viruses and viroids and with those that are yet to be discovered in the uncertain scenario of climate change.
      PubDate: 2017-06-30T00:55:58.015283-05:
      DOI: 10.1111/aab.12371
       
  • Brazilian melon landraces resistant to Podosphaera xanthii are unique
           germplasm resources
    • Authors: E.W.L.P. Nunes; C. Esteras, A.O. Ricarte, E.M. Martínez, M.L. Gómez-Guillamón, G.H.S. Nunes, M.B. Picó
      Abstract: Podosphaera xanthii is the most important causal agent of powdery mildew in melon, a crop ranked within the most economically important species worldwide. The best strategy to face this fungus disease, which causes important production losses, is the development of genetically resistant cultivars. Genetic breeding programmes require sources of resistance, and a few ones have been reported in melon, mostly in Momordica and Acidulus horticultural groups. However, the existence of many races that reduces the durability of the resistance makes necessary to find new resistant genotypes with different genetic backgrounds.In this work, Brazilian germplasm, together with a set of Indian landraces, and the COMAV's (Institute for the Conservation and Breeding of Agricultural Biodiversity) melon core collection, representing the whole variability of the species, were assessed for resistance against some common races in Spain and Brazil and genotyped with a 123-SNP (single nucleotide polymorphisms) genotyping platform to study the molecular relationships of the resistant accessions. In the first experiment, carried out in Valencia (Spain) in 2013, seventy-nine melon accessions were evaluated using artificial inoculation. Five accessions selected as resistant were also evaluated against races 1, 3, and 5 in Mossoró (Brazil, 2015) and against race 3.5 in Valencia (2016) under greenhouse conditions, and under four field conditions in Brazil. The accessions, AL-1, BA-3, CE-3, and RN-2, within the Brazilian collection, presented resistance against all the races of P. xanthii assayed in all conditions tested. AL-1, CE-3 and RN-2 were molecularly more similar to wild agrestis and Acidulus melons from Asia and Africa, while BA-3 grouped with Momordica types. Molecular analysis also confirmed that these new Brazilian sources of resistance differ from those previously reported, constituting interesting materials to encourage genetic breeding programmes, especially in Brazil and Spain.
      PubDate: 2017-06-30T00:55:24.093169-05:
      DOI: 10.1111/aab.12370
       
  • Detection of Southern tomato virus by molecular hybridisation
    • Authors: A.V. Puchades; C. Carpino, A. Alfaro-Fernandez, M.I. Font-San-Ambrosio, S. Davino, J. Guerri, L. Rubio, L. Galipienso
      Abstract: Southern tomato virus (STV) is a double-stranded RNA (dsRNA) virus belonging to the genus Amalgavirus from the family Amalgamaviridae. STV has been detected in tomato plants showing symptoms of stunting, fruit discoloration and size reduction, although its role on symptom development is unclear. Also, little is known about the incidence and epidemiology of this virus and how it spreads in tomato crops. In this work, we developed a molecular hybridisation method by using a digoxigenin-labelled RNA probe based on the nucleotide sequence of the STV putative coat protein which was tested with different procedures for preparation of plant material. This technique was sensitive enough to detect STV from sap extracts (obtained just by grinding in buffer) from different plant tissues such as leaves, fruits, roots and seeds. This procedure is suitable for field surveys since it allows a cheap and quick processing of a high number of samples. Surveys performed in three important tomato production areas (Peninsular Spain, the Canary Islands and Sicily) showed that STV is widely spread, with incidences ranging from 18% to 74% in different local and commercial tomato varieties.
      PubDate: 2017-06-27T21:35:29.78246-05:0
      DOI: 10.1111/aab.12367
       
  • A chitinase from Euphorbia characias latex is a novel and powerful
           plant-based pesticide against Drosophila suzukii
    • Authors: S. Martos; D. Spanò, N. Agustí, C. Poschenrieder, F. Pintus, L. Moles, R. Medda
      Abstract: Drosophila suzukii attacks on developing soft fruits have recently caused important economic losses in Europe. This study explores the effectiveness of a new control strategy against this insect pest that is based on a plant chitinase extracted from the latex of the Mediterranean spurge, Euphorbia characias. The ability of the purified Euphorbia latex chitinase (ELC) to degrade the chitin exoskeleton of D. suzukii was assessed using confocal laser scanning microscopy. ELC treatment caused reduced larval growth, higher mortality and notable degradation of external insect structures. Therefore, the chitinase may induce a double effect on the D. suzukii larvae, a direct injury on the larval bodies and an action as antifeedant. The effects of the ELC treatment were also tested on leaves of the insect's host plants, Fragaria × ananassa and Rubus idaeus, using physiological parameters (chlorophyll concentration, chlorophyll fluorescence, leaf gas exchange and water potential) and defence gene expression (FaPGIP, FaChi2_1 and FaChi2_2) as stress indicators. ELC at concentrations effective against D. suzukii did not damage the host plants. Only plant defence gene expression was somewhat enhanced during the early hours after ELC application. In conclusion, ELC, a natural product, proved to be an effective tool for use in the development of an environmentally friendly integrated management strategy against D. suzukii, a pest whose control by conventional chemical insecticides is problematic.
      PubDate: 2017-06-26T20:33:01.624411-05:
      DOI: 10.1111/aab.12369
       
  • The role of domestication and maternal effects on seed traits of
           crop–wild sunflower hybrids (Helianthus annuus)
    • Authors: F. Hernández; L.I. Lindström, E. Parodi, M. Poverene, A. Presotto
      Abstract: Hybridisation between crops and their wild relatives may promote the evolution of weeds. Seed germination and dormancy are the earliest life-history traits and are highly influenced by the maternal parent. However, the ecological role of the maternal effect on seed traits in the evolution of crop–wild hybrids has received little attention. In this study, we test the relative importance of maternal and hybridisation effects on seed traits of the first generation of crop–wild sunflower hybrids (Helianthus annuus). Seed germination was tested in two wild populations with contrasting dormancy, two cultivated materials and their reciprocal crosses at four different times after harvest and three different temperatures. Seed germination at each of the four times, after ripening response and secondary dormancy were recorded along with four morphological traits. Additionally, the pericarp anatomy was analysed with light and scanning electron microscopy. We observed strong maternal effects on all seed traits. Seed germination, morphology and pericarp anatomy differed largely between the crop and wild seeds and these traits in the crop–wild hybrids resembled their female parent. Slight but significant hybridisation effects were observed in germination, mainly in seeds produced on wild plants. Crop hybridisation changed seed germination, the after ripening response and secondary dormancy in the crop direction. Morphological and anatomical traits associated with domestication strongly correlated with the observed differences in seed germination and dormancy in crop–wild sunflower hybrids. The large maternal effects along with the evolutionary divergence in seed traits were responsible for the large phenotypic differences observed in crop–wild hybrids with the same genetic composition. Wild-like seed traits of hybrids suggest that there are no barriers to crop gene introgression at the seed level whereas crop-like seed traits could be strongly selected against, conditioning the selection of traits expressed later in the life cycle and in the next generations.
      PubDate: 2017-06-15T00:35:35.230304-05:
      DOI: 10.1111/aab.12368
       
  • Seed treatment with selected plant growth-promoting rhizobacteria
           increases maize yield in the field
    • Authors: G. Breedt; N. Labuschagne, T.A. Coutinho
      Abstract: Maize, Zea mays is the most important grain crop in South Africa and is a staple food in many African countries. The beneficial effects of plant growth-promoting rhizobacteria on crop growth and yield have been well documented, but obtaining reproducible results under field conditions is often difficult. In the current study, five selected rhizobacterial strains that showed plant growth-promoting activities in pilot studies were evaluated for potential enhancement of maize yield under field conditions. The five strains together with a commercial standard were assessed as seed treatments of maize over three seasons in four different soil types. The strains were identified on the basis of 16S rRNA sequencing as Lysinibacillus sphaericus (T19), Paenibacillus alvei (T29), Bacillus safensis (S7) Bacillus pumilus (A26) and Brevundimonas vesicularis (A40). The best yield increases in maize were obtained during the 2011/2012 and 2012/2013 seasons in the Shortlands ecotope with the rhizobacterial strains T19, T29 and S7, resulting in yield increases ranging from 24% to 34%. Strain T19 rendered the most consistent yield increases during the three successive field trials amounting to 33% and 24% in Shortlands ecotope and 12% in Clovalley ecotope, respectively. During 2013/2014 a consortium of three strains, viz. T19, S7 and A26 gave a 32% yield increase in Clovalley ecotope. All the rhizobacterial strains solubilised phosphate in vitro except T19. Strain T29 showed the best nitrogen-fixing activity in vitro, proliferating on a nitrogen-free substrate and also producing ammonia. All the strains tested positive for indole acetic acid production. The current study demonstrates the ability of rhizobacterial strains T19, T29, S7 and A26 applied as seed treatments to significantly enhance maize yield in the field, making development and commercialisation of these strains a viable option.
      PubDate: 2017-06-15T00:35:21.83683-05:0
      DOI: 10.1111/aab.12366
       
  • A discussion on disease severity index values. Part I: warning on inherent
           errors and suggestions to maximise accuracy
    • Authors: K.S. Chiang; H.I. Liu, C.H. Bock
      Abstract: A special type of ordinal scale comprising a number of intervals of known numeric ranges can be used when estimating severity of a plant disease. The interval ranges are most often based on the percent area with symptoms [e.g. the Horsfall–Barratt (H–B) scale]. Studies in plant pathology and plant breeding often use this type of ordinal scale. The disease severity is estimated by a rater as a value on the scale and has been used to determine a disease severity index (DSI) on a percentage basis, where DSI (%) = [sum (class frequency × score of rating class)]/[(total number of plants) × (maximal disease index)] × 100. However, very few studies have investigated the effects of different scales on accuracy of the DSI. Therefore, the objectives of this study were to investigate the process of calculating a DSI on a percentage basis from ordinal scale data, and to use simulation approaches to explore the effect of using different methods for calculation of the interval range and the nature of the ordinal scales used on the DSI estimates (%). We found that the DSI is particularly prone to overestimation when using the above formula if the midpoint values of the rating class are not considered. Moreover, the results of the simulation studies show that, if rater estimates are unbiased, compared with other methods tested in this study, the most accurate method for estimation of a DSI is to use the midpoint of the severity range for each class with an amended 10% ordinal scale (an ordinal scale based on a 10% linear scale emphasising severities ≤50% disease, with additional grades at low severities). As for biased conditions, the accuracy for calculating DSI estimates (%) will depend mainly on the degree and direction of the rater bias relative to the actual mean value.
      PubDate: 2017-06-06T03:20:39.04349-05:0
      DOI: 10.1111/aab.12362
       
  • Persistence of transgenes in wild rice populations depends on the
           interaction between genetic background of recipients and environmental
           conditions
    • Authors: S.S. Dong; M.Q. Xiao, D.X. Ouyang, J. Rong, B.-R. Lu, J. Su, F. Wang, J.K. Chen, Z.-P. Song
      Abstract: The persistence of transgenes in wild populations may cause unintended ecological consequences, and the possibility of transgenes' persistence and introgression is dependent on fitness performance of transgenic crop–wild hybrids. To investigate the effects of transgene and genotype × environment on the fitness of crop–wild rice hybrids, a total of 11 cross-combination progenies between insect-resistant transgene (CpTI and Bt/CpTI) rice lines and wild rice (Oryza rufipogon) were evaluated at different sites with contrasting insect treatments. The results showed that fitness performance varied between transgenic hybrids having different wild parents and under different environmental conditions, indicating that fitness effects of transgenes on hybrid progenies depend heavily on the genetic background of recipient plants and growing environment. Significant fitness advantages conferred by transgenes were found only in some hybrids under high insect pressure condition, demonstrating that the level of target insects in the field environment influences the persistence and spread of insect-resistant transgenes in wild rice populations. These findings suggest that evolutionary fate of escaped transgenes is different in wild populations with diverse genetic backgrounds under various environmental conditions.
      PubDate: 2017-06-01T02:50:28.325977-05:
      DOI: 10.1111/aab.12365
       
  • Probability distributions for marketable pods and white mould on snap bean
    • Authors: D.A. Shah; H.R. Dillard, S.J. Pethybridge
      Abstract: White mould, caused by Sclerotinia sclerotiorum, is one of the most recalcitrant diseases of snap bean. Probability distributions suitable for describing the total number of marketable pods (hereafter simply referred to as pods) per plant, as well as for the number of pods and stems with white mould per plant, have not been identified. The total number of pods and the number of pods and stems with white mould were measured on a per plant basis in plots of processing snap bean (var. Hystyle) in New York. The total number of pods per plant ranged from 0 to 29, and was best described by the Pólya-Aeppli distribution. The number of pods and the number of stems with white mould per plant were well-described by the negative binomial (NB) distribution. A Sarmanov bivariate distribution with NB marginals was derived and fitted to the joint data on the number of pods and stems with white mould per plant, accounting for correlation between pods and stems with white mould on the same plant. The bivariate distribution was used to formulate an empirical equation for the incidence of plants with white mould as a function of the average number of pods and stems with white mould per plant. The results represented a more complete understanding of the distributional properties of white mould in snap bean.
      PubDate: 2017-05-23T04:11:24.960644-05:
      DOI: 10.1111/aab.12363
       
  • Ethylenediamine-N,N′-disuccinic acid mitigates salt-stress damages in
           strawberry by interfering with effects on the plant ionome
    • Authors: R. Aslantas; I. Angin, M. Kose, N. Bernstein
      Abstract: This study evaluated the hypothesis that the organic chelant ethylenediamine-N,N′-disuccinic acid (EDDS) mitigates plant damage under salinity, and that this is accomplished by EDDS-induced effects on cation uptake. Damaging effects of salinity on plants often involve inhibited uptake of nutritional cations, such as K and Ca, and excessive accumulation of Na. Therefore, mechanisms that improve uptake of K and Ca, or reduce Na uptake, have a potential for ameliorating salinity damages. Organic chelants increase heavy-metal cation availability at the site of uptake and increase their uptake by the roots or in planta transport. Although organic chelants are routinely used in agriculture to enhance uptake of heavy-metal cations into plants, and for soil bioremediation, their effect on uptake of cation-macronutrients is not known, and neither is their impact on plant function under salinity. In this study, we evaluated the response of strawberry plants to EDDS application (0, 1, 3 and 5 mmol kg soil−1), under six levels of NaCl (0, 3, 6, 9, 12 and 15 mmol L−1). EDDS application under salinity improved vegetative development, as well as reproductive growth and chlorophyll content, with statistically significant interaction between chelant dosage and level of salinity. The mitigation of salinity damage by EDDS occurred at high salinity treatments (from 9 mM NaCl). Application rates of 1–3 mmol EDDS kg−1 were optimal for mitigating salinity effects on reproductive development, but in accordance with the extent of chelant-induced accumulation of the macronutrients K, Ca and P in the leaves, higher application rates (3–5 mmol EDDS kg−1) were required for optimal improvement of vegetative development. These results suggest that EDDS improves plant function under mild salinities by interfering with salinity effects on the plant ionome.
      PubDate: 2017-05-23T03:40:29.654703-05:
      DOI: 10.1111/aab.12364
       
  • Effects of Grapevine leafroll-associated virus 3 on the physiology in
           asymptomatic plants of Vitis vinifera
    • Authors: R. Montero; H. El aou ouad, D. Pacifico, C. Marzachì, N. Castillo, E. García, N.F. Del Saz, I. Florez-Sarasa, J. Flexas, J. Bota
      Abstract: Grapevine leafroll disease is one of the most important viral diseases of grapevine (Vitis vinifera) worldwide. Grapevine leafroll-associated virus 3 (GLRaV-3) is the most predominant virus species causing this disease. Therefore, it is important to identify GLRaV-3 effects, especially in plants which do not systematically show visual symptoms. In this study, effects of GLRaV-3 on grapevine physiology were evaluated in asymptomatic plants of Malvasía de Banyalbufar and Cabernet Sauvignon cvs. Absolute virus quantification was performed in order to determine the level of infection of the treatment. The net carbon dioxide (CO2) assimilation (AN) and electron transport rate (Jflux) were the main parameters affected by the virus. The AN reduction in infected plants was attributed to restrictions in CO2 diffusion caused by anatomical leaf changes and a reduction of Rubisco activity. Those effects were more evident in Malvasia de Banyalbufar plants. The reduction of AN leads to a decrease in the total oxygen uptake rate by the activity of the cytochrome oxidase pathway, producing slight differences in plant growth. Therefore, even though no symptoms were expressed in the plants, the effects of the virus compromised the plant vital processes, showing the importance of early detection of the virus in order to fight against the infection.
      PubDate: 2017-05-17T03:41:11.103456-05:
      DOI: 10.1111/aab.12356
       
  • Lessons learned from the virus indexing of Musa germplasm: insights from a
           multiyear collaboration
    • Authors: C. De Clerck; K. Crew, I. Van den houwe, L. McMichael, C. Berhal, L. Lassois, M. Haissam Jijakli, N. Roux, J. Thomas, S. Massart
      Abstract: The Bioversity International Transit Center (ITC) for banana hosts more than 1500 accessions largely covering the genetic diversity of the genus Musa. Its objective is to conserve this genetic diversity and to supply plant materials to users worldwide. All the Musa accessions must be tested for virus presence and, if infected, virus elimination must be attempted, to enable the supply of virus-free plant material. An international collaborative effort launched under the auspices of Bioversity International (2007–2013) finally led to the implementation of a two-step process to test the accessions. The first step, called pre-indexing, involved only molecular tests and was designed as a pre-screen of new germplasm lines or existing accessions to reduce the need for post-entry virus therapy and repeated virus indexing. The second step, called full indexing, was performed on either older existing accessions or newer accessions which tested negative during pre-indexing, and involved molecular tests, transmission electron microscopy (TEM) and symptom observation. In total, 270 germplasm lines (434 samples) were pre-indexed; while full indexing was carried out on 243 accessions (68 of which had been pre-indexed). A significant proportion of the samples tested during pre-indexing was infected with at least one virus (68%), showing the utility of this early pre-screening step. Banana streak OL virus and Banana mild mosaic virus were the most commonly detected viruses during both pre- and full indexing. For 22 accessions, viral particles were observed by TEM in full indexing while the molecular tests were negative, underlining the importance of combining various detection techniques. After full indexing, viruses were not detected in 166 accessions, which were then released for international distribution from the ITC. This publication exemplifies how the practical application of diagnostic protocols can raise fundamental questions related to their appropriate use in routine practice and the need for their continuous monitoring and improvement after their first publication.
      PubDate: 2017-04-20T04:51:31.242832-05:
      DOI: 10.1111/aab.12353
       
  • Allometric equations for yield predictions of enset (Ensete ventricosum)
           and khat (Catha edulis) grown in home gardens of southern Ethiopia
    • Authors: B.T. Mellisse; K. Descheemaeker, M.J. Mourik, G.W.J. Ven
      Abstract: Enset is a large, single-stemmed perennial herbaceous plant domesticated as a staple food crop only in Ethiopia. Khat is a perennial plant cultivated for its economically important leaves and twigs that are the sources of stimulant when chewed. We address the issue of yield estimation of both crops, as they are important for the livelihoods of smallholders in the home garden systems in Southern Ethiopia and have received little attention so far. The objective of this study was to develop linear allometric models for estimating the edible (food and feed) and commercial yields of enset and khat plants, respectively. Data were collected from 20 enset and 100 khat plants. Diameter at 50-cm height (d50), pseudostem height (hp) and their combination were good predictor variables for the food products of enset with adjusted R2 values above 0.85, while d50, hp, edible pseudostem height (hep), total height (ht) and their combination were good predictor variables for the feed products of enset with adjusted R2 values above 0.70. For dwarf khat plants crown area (ca) combined with total height (ht) resulted in the best prediction with an adjusted R2 of 0.77, while the leaf and twig dry weight for tall khat plants was best predicted by ca with adjusted R2 of 0.43. In all cases linear models were used.
      PubDate: 2017-04-18T04:05:49.499485-05:
      DOI: 10.1111/aab.12350
       
  • Effects of species and soil-nitrogen availability on root system
           architecture traits – study on a set of weed and crop species
    • Authors: D. Moreau; F. Abiven, H. Busset, A. Matejicek, L. Pagès
      Abstract: Better managing crop : weed competition in cropping systems while reducing both nitrogen and herbicide inputs is a real challenge that requires a better understanding of crop and weed root architecture in relation to soil-nitrogen availability. An original approach was used which considered the parameters of a simulation model of root architecture as traits to analyse (a) the interspecific diversity of root system architecture, and (b) its response to soil-nitrogen availability. Two greenhouse experiments were conducted using three crop and nine weed species grown at two contrasted concentrations of soil-nitrogen availability. Plant traits were measured to characterise both overall plant growth and root architecture, with a focus on primary root emergence, root elongation and branching. The studied root traits varied among species (from a twofold to a fourfold factor, depending on the trait), validating their use as indicators to analyse the interspecific variability of root architecture. The largest interspecies differences were for two traits: ‘maximal apical root diameter’ and ‘interbranch distance’ (distance between two successive laterals on the same root). Conversely, most of the studied root traits varied little with soil-nitrogen availability (from no variation to a 1.1-fold factor, depending on the trait) even though soil-nitrogen availability varied with a 17-fold factor and impacted the overall shoot and root biomass. So, the root traits used in this article are stable whatever soil-nitrogen availability. As they reflect processes underlying root system architecture, this low effect of nitrogen suggests that the rules governing root architecture are little affected by plant nitrogen status and soil-nitrogen availability. We propose that the determinants of differences in root system architecture between soils with contrasted nitrogen availability mainly originate from differences in the amount of carbon allocated to and within the root system. Characterising each plant species by a combination of root traits gave insights regarding the potential species competitive ability for soil resources in agroecosystems.
      PubDate: 2017-04-11T03:10:29.020179-05:
      DOI: 10.1111/aab.12355
       
  • New insights on Flavescence dorée phytoplasma ecology in the vineyard
           agro-ecosystem in southern Switzerland
    • Authors: P. Casati; M. Jermini, F. Quaglino, G. Corbani, S. Schaerer, A. Passera, P.A. Bianco, I.E. Rigamonti
      Abstract: Phytoplasmas associated with Flavescence dorée (FDp) grapevine disease are quarantine pathogens controlled through mandatory measures including the prompt eradication and destruction of diseased plants, and the insecticide treatments against the insect vector, the ampelophagous leafhopper Scaphoideus titanus. In the present study, a multidisciplinary approach has been applied to investigate the FDp ecological cycle in a test vineyard agro-ecosystem in Canton Ticino, south Switzerland. Despite the scarce population density of S. titanus, a regular trend of new infections (3.4% of the total vines) through the years was observed. The leafhopper Orientus ishidae was found as the most abundant among the captured insect species known as phytoplasma vectors (245 out of 315 specimens). The population of O. ishidae was evidenced prevalently (167 specimens) in the south-western side of the vineyard and within the neighbouring forest constituted mainly by hazel (Corylus avellana) and willow (Salix spp.). These plant species were found infected by FDp related strains (30% of analysed trees) for the first time in this study. Interestingly, O. ishidae was found to harbour FDp related strains in high percentage (26% of the analysed pools). In addition, 16SrV phytoplasma group was detected for the first time in the insect Hyalesthes obsoletus and a FDp related strain in Thamnotettix dilutior, present in low populations within the test vineyard. Molecular characterisation and phylogenetic analyses of methionine aminopeptidase (map) gene sequences of FDp and related strains, here identified, revealed the great prevalence of the map-type FD2 in grapevines (97%) and in O. ishidae pools (72%). Such a map-type was found also in hazel and in T. dilutior, but not in S. titanus. Moreover, map-types FD1 and FD3 were identified for the first time in Switzerland in several host plants and phytoplasma vectors, including grapevine (FD1), S. titanus (FD1) and O. ishidae (FD1 and FD3). Based on the data obtained in this study, it is reasonable to hypothesise that the ecological cycle of FDp could be related not exclusively to the grapevine-specific feeding diet of S. titanus, but it could include other insect vector(s) and/or plant host(s). Further studies will be needed to prove the role of O. ishidae as vector able to transmit FDp from wild plants (e.g. hazel) to grapevine.
      PubDate: 2017-04-07T04:38:33.379387-05:
      DOI: 10.1111/aab.12359
       
  • A real-time PCR assay for improved rapid, specific detection of
           Cryphonectria parasitica
    • Authors: S. Rubio; A. Barnes, K. Webb, J. Hodgetts
      Abstract: Cryphonectria parasitica, an ascomycete fungus, is the causal agent of chestnut blight. This highly destructive disease of chestnut trees causes significant losses, and is therefore a regulated pathogen in Europe. Existing methods for the detection of C. parasitica include morphological identification following culturing, or PCR; however, these are time-consuming resulting in delays to diagnosis. To allow improved detection, a new specific real-time PCR assay was designed to detect C. parasitica directly from plant material and fungal cultures, and was validated according to the European Plant Protection Organisation (EPPO) standard PM 7/98. The analytical specificity of the assay was tested extensively using a panel of species taxonomically closely related to Cryphonectria, fungal species associated with the hosts and healthy plant material. The assay was found to be specific to C. parasitica, whilst the analytical sensitivity of the assay was established as 2 pg µL−1 of DNA. Comparative testing of 63 samples of naturally infected plant material by the newly developed assay and traditional morphological diagnosis demonstrated an increased diagnostic sensitivity when using the real-time PCR assay. Furthermore the assay is able to detect both virulent and hypovirulent strains of C. parasitica. Therefore the new real-time PCR assay can be used to provide reliable, rapid, specific detection of C. parasitica to prevent the accidental movement of the disease and to monitor its spread.
      PubDate: 2017-04-07T04:01:37.548846-05:
      DOI: 10.1111/aab.12354
       
  • First report of the gall midge Asphondylia serpylli on thyme (Thymus
           vulgaris), and identification of the associated fungal symbiont
    • Authors: B. Zimowska; G. Viggiani, R. Nicoletti, A. Furmańczyk, A. Becchimanzi, I. Kot
      Abstract: Asphondylia spp. (Diptera: Cecidomyiidae) are known for inducing gall formation on many diverse plants in both wild and agricultural contexts. The species Asphondylia serpylli is herewith reported for the first time on thyme (Thymus vulgaris) cropped in Poland. The associated fungus has been identified as Botryosphaeria dothidea, representing its first record from cecidomyiid galls on a species of Lamiaceae. Moreover, a short account is given on the parasitoid species active in this particular ecological context. These findings point out the basic role of B. dothidea in the organization of these three-component biotic systems regardless of the varied assortments between the midge species and their host plant.
      PubDate: 2017-03-31T06:35:25.306197-05:
      DOI: 10.1111/aab.12360
       
  • Influence of limiting and regulating factors on populations of Asian
           citrus psyllid and the risk of insect and disease outbreaks
    • Authors: B.J. Udell; C. Monzo, T.M. Paris, S.A. Allan, P.A. Stansly
      Abstract: Diaphorina citri, known as the Asian citrus psyllid (ACP), is the insect vector of a devastating citrus disease (huanglongbing; HLB), which has caused billions of dollars in damage in Florida since its detection in 2005. Data from long-term monitoring programs in two Florida citrus groves were used to assess ACP demography and population ecology, which is needed to implement more effective management strategies for HLB. Seasonal patterns and correlations between ACP density estimates and a suite of environmental and community indicators, previously shown to influence ACP demography, were described and interpreted. Data were evaluated for evidence for spatial clustering and density-dependent recruitment of ACP in a major outbreak event using Taylor power law analysis and by fitting a stochastic Beverton–Holt recruitment model using state-space approach. Strong evidence for density-dependent recruitment and spatial clustering was found and should be considered for future modelling work as it can greatly influence ACP populations by affecting their growth rates, dispersal behaviour and morphology, as well as HLB transmission. Observations of ACP density and dispersion in space and time, along with the estimated parameters from the Beverton–Holt model, suggested that intraspecific competition for resources may initiate both local, then widespread dispersal process, thus affecting grove-wide and area-wide HLB transmission. When these results were synthesised with those of parallel studies, the removal of several of these regulating factors in a single year could lead to widespread disease of the entire crop in a grove, and likely surrounding groves as well. We provide the first field evidence of the consequences of back-to-back ACP colonisation on the rapid spread of the HLB in a grove (a mechanism previously demonstrated in laboratory settings). We stress the importance of proper integrated pest management and area-wide management to prevent such outbreaks.
      PubDate: 2017-03-31T06:30:43.440895-05:
      DOI: 10.1111/aab.12349
       
  • Effect of five fungicides with different modes of action on cobweb disease
           (Cladobotryum mycophilum) and mushroom yield
    • Authors: J. Carrasco; M.J. Navarro, M. Santos, F.J. Gea
      Abstract: The fungicides chlorothalonil, metrafenone, prochloraz-Mn, thiabendazole and thiophanate-methyl were tested in vitro and in vivo for their effect on Cladobotryum mycophilum, the mycoparasite that causes cobweb disease in white button mushroom. In vitro experiments showed that metrafenone (EC50= 0.025 mg L−1) and prochloraz-Mn (EC50= 0.045 mg L−1) were the most effective fungicides for inhibiting the mycelial growth of C. mycophilum. Selectivity indexes of the tested fungicides on both C. mycophilum and Agaricus bisporus indicated that metrafenone was also the most selective fungicide, while chlorothalonil was the most toxic fungicide against A. bisporus mycelium. The in vivo efficacy of fungicides for controlling cobweb was evaluated in three mushroom cropping trials, which were artificially inoculated with C. mycophilum (106 conidia m−2). Prochloraz-Mn provided good control, although the surface colonised by cobweb reached 12% by the end of the crop cycles. None of the inoculated cropping trials treated with metrafenone showed any cobweb disease symptoms, and neither were any significant phytotoxic effects on mushroom yield recorded. These results indicated that metrafenone can be used as an alternative to prochloraz-Mn in the control of cobweb disease.
      PubDate: 2017-03-31T06:20:24.830082-05:
      DOI: 10.1111/aab.12352
       
  • Phenological growth stages of quinoa (Chenopodium quinoa) based on the
           BBCH scale
    • Authors: V. Sosa-Zuniga; V. Brito, F. Fuentes, U. Steinfort
      Abstract: Quinoa (Chenopodium quinoa) is a pseudocereal native from the Andean region of South America that has increased in importance worldwide. Quinoa is now considered an alternative to traditional crops in a climate change scenario, considering its ability to adapt to marginal soils, droughts and frosts. Despite the interesting agronomic and nutritional features of this crop, research into quinoa is characterised by individual attempts to define its phenological stages without an international consensus. A unique criterion to quantify the phenology of quinoa could become a useful tool for researchers and plant breeders in future work by standardising this information for international cooperation. In this article, a proposed scale of the phenological growth stages of quinoa based on the BBCH coding system (Biologische Bundesanstalt Bundessortenamt und CHemische Industrie) was developed. Growth stages were described utilising the decimal code of the BBCH system, and figures were included for the most representative stages.
      PubDate: 2017-03-31T06:15:43.248042-05:
      DOI: 10.1111/aab.12358
       
  • Temporal and spatial dynamics of Tomato spotted wilt virus and its vector
           in a potato crop in Argentina
    • Authors: A.E. Salvalaggio; P.M. López Lambertini, G. Cendoya, M.A. Huarte
      Abstract: The nature of spatial and temporal dynamics of Tomato spotted wilt virus (TSWV) and its vector in a potato crop cv. Innovator without insecticide application is analysed. Seed tuber was analysed for the presence of TSWV as a source of initial inoculum. The presence of plants with symptoms of TSWV was evaluated by visual observation and DAS-ELISA analysis to confirm the virus infection. Thrips species were collected from leaves and inflorescences and identified under stereomicroscope. The distribution of symptomatic plants and thrips species was recorded five times at 14 days intervals. The initial seed tuber infection was of 1.1%. Disease incidence was 0% at 29 days after planting (DAP), 0.2% at 43 DAP, 2.2% at 56 DAP, 11.6% at 70 DAP and 14.6% at 84 DAP. The progress of the disease was adequately described by a Logistic model [y = 0.15/(1 + 1205372.93 × exp (−0.22 × DAP))]. Thrips vector species identified as resident in the crop during the whole cycle were Thrips tabaci (n = 423), Frankliniella occidentalis (n = 141) and as occasional species, F. schultzei (n = 34) and F. gemina (n = 5) were found. At 43 and 56 DAP a random distribution pattern was observed and the thrips species found were T. tabaci (n = 188) and F. occidentalis (n = 105). An aggregated pattern was determined at 70 and 84 DAP. Spatial patterns of the disease spread suggest a polycyclic epidemic with TSWV secondary spread in the potato crop. Multiple control measures were deduced from these epidemiological results like virus testing in tubers, removal of external virus infection sources and thrips control.
      PubDate: 2017-03-28T03:30:26.533028-05:
      DOI: 10.1111/aab.12357
       
  • Detection of lethal yellowing phytoplasma in coconut plantlets obtained
           through in vitro germination of zygotic embryos from the seeds of infected
           palms
    • Authors: C. Oropeza; I. Cordova, C. Puch-Hau, R. Castillo, J.L. Chan, L. Sáenz
      Abstract: Lethal yellowing (LY) is a disease caused by 16SrIV phytoplasmas that has devastated coconut plantations in the Americas. An alternative means of phytoplasma spread is through seeds. Therefore, we used a novel approach based on plumules from the embryos of LY-diseased coconut palms. We cultured the plumules in vitro to determine the presence of phytoplasma DNA in the plantlets. In the first assay, 185 embryos were obtained. The results showed positive detection in 20 samples (11%) with the nested PCR and in 59 samples (32%) with the TaqMan real-time PCR. A second assay was designed to trace plumules to their respective embryos and haustorial tissues to determine whether they had derived from an embryo with positive LY detection; a total of 124 embryos were obtained. The results showed no positive detection with the nested PCR and positive detection in 42 of the haustorial tissue samples (32%) with the TaqMan real-time PCR. The 124 plumules isolated from the embryos were cultivated under in vitro conditions and divided into two groups. Group A was followed for shoot formation and Group B was followed to the plantlet stage. After 3 months of cultivation, 33 cultures (50%) within Group A became necrotic; the rest were analysed to evaluate LY phytoplasma DNA with the TaqMan real-time PCR assay and 14 (42%) tested positive. After 18 months of cultivation, 20 cultures (34%) within Group B became necrotic. The rest were analysed for the detection of the LY phytoplasma DNA, and 15 and 11 (39% and 29%) of the samples tested positive with the TaqMan real-time PCR and nested PCR assays, respectively. Blast analysis of the sequenced products revealed that the sequences showed 99% homology with LY-phytoplasma subgroup 16SrIV-A. The results presented here demonstrate, for the first time, the occurrence of the transmission of LY phytoplasmas from coconut embryos to plantlets.
      PubDate: 2017-03-14T02:05:38.907363-05:
      DOI: 10.1111/aab.12351
       
  • Ecology and diversity of plant viruses, and epidemiology of plant
           virus-induced diseases
    • Authors: M.A. Aranda; J. Freitas-Astúa
      Pages: 1 - 4
      PubDate: 2017-06-05T05:37:43.914437-05:
      DOI: 10.1111/aab.12361
       
 
 
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