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Journal of Plant Diseases and Protection
Number of Followers: 2  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1861-3829 - ISSN (Online) 1861-3837 Published by Springer-Verlag  [2468 journals]
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- First report of Fusarium anthophilum causing drying on Butia odorata in
Rio Grande do Sul, Brazil-
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Abstract: Abstract Butia spp. is a palm tree native to southern Brazil and Uruguay. The fruits are consumed fresh and used to make many food products, while the leaves are commonly used to make crafts. In January 2018, severe symptoms of wilt and drying were identified in clusters of Butia odorata occurring on the leaf and the rachis (in a proportion of 50% of leaf area). The pathogen was isolated from a stump extracted from a symptomatic tree. The morphologic characters showed a presence of macroconidia and microconidia with a classic salmon color of some species of the Fusarium genus. The molecular identification of the locus of actin (ACT), calmodulin (CAL), factor elongation 1-alpha (TEF1) and histone (HIS3), confirmed the identity of Fusarium anthophilum. This finding will help growers and agronomists prevent and manage this disease. To the best of our knowledge, this is the first report of Fusarium antophilum causing disease in Butia odorata.
PubDate: 2023-12-03
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- Evaluation of vegetable oil as oviposition deterrents for the management
of pink bollworm, Pectinophora gossypiella (Saunders) in cotton-
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Abstract: Abstract Oviposition deterrents are the info-chemicals that modifies the behavior of conspecific female insects either to settle on the treated surface or to lay eggs thereafter, reducing intra-specific competition. Drawing from our prior research, it has been established that the fatty acids (Oleic and linoleic acid) found in vegetable oils exhibit properties of oviposition deterrence. The present study was designed to investigate the oviposition deterrent activity of vegetable oils against pink bollworm. Six different vegetable oils, namely groundnut, sunflower, soybean, rice bran, safflower and sesame containing oleic and linoleic acid as major fatty acids were selected and evaluated under laboratory and field conditions. Under laboratory conditions, oils were tested at concentrations ranging from 0.5 to 3.0%, with methanol as control. Cotton twigs with squares served as the oviposition substrate and the total number of eggs laid by the moth was counted and compared to control. The results demonstrated a significant reduction in number of eggs laid as evident from the avoidance index (AI) and percent effective deterrence (PED) values of vegetable oil treatments. Descending order of oviposition deterrent efficacy as revealed from AI and PED values, groundnut (AI = 0.74, PED = 84.40%) > soybean (0.67, 79.87%) > sesame (0.65, 78.59%) > sunflower (0.59, 74.09%) > rice bran (0.57, 71.93%) > safflower (0.55, 71.09%). Our findings were further validated through field studies conducted during 2019–2020 and 2020–2021, confirming effectiveness of the selected vegetable oils in reducing the boll damage. Study demonstrates the promising oviposition deterrent effect of vegetable oils against Pectinophora gossypiella and hold great potential as an eco-friendly component in integrated pest management program of cotton.
PubDate: 2023-12-03
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- Correction: Legislative situation of botanicals used in plant protection
in the European Union-
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PubDate: 2023-12-01
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- “Solanum torvum mediates protection against the nematode Meloidogyne
incognita in neighboring plants”-
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Abstract: Abstract This study investigates the natural repellency of Solanum torvum Sw. (herein Torvum) to the Meloidogyne incognita (M. incognita) and the influence on neighboring plants. Torvum is a solanaceous species that has demonstrated high resistance to several pathogens and pests transmitted from the soil, including M. incognita. Inoculation experiments were performed on five Solanaceae species. The results confirmed the high resistance of Torvum to M. incognita and its ability to have beneficial effects on closely grown plants, evidenced by a significant reduction of galls and egg masses on the highly susceptible plants of Solanum melongena L. and Solanum lycopersicum. We show that the resistance of Torvum is due to impenetrability to M. incognita. We show that roots of in vitro grown Torvum present distinguished trichomes and root hair phenotypes. In our previous study, the Torvum transcriptome revealed differentially expressed genes with significant enrichment for the sesquiterpenoid and chitinase genes. Re-analyzing the transcriptomic data of our previous work, we found several genes modulated among those of Dirigent/Disease Resistance Response (DIR/DRR) proteins, then validated through qRT-PCR. The resistant plants showed DIR-DRR genes highly expressed compared to susceptible in the controls and inoculated plants, thus suggesting a role in plant defense. We proposed a schematic model to explain the protection potential of Torvum against M. incognita infection and possibly new opportunities in the plant protection.
PubDate: 2023-12-01
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- Effect of biological activity of Carapa procera seed oil on the tomato
leaf miner, Tuta absoluta-
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Abstract: Abstract Tuta absoluta poses a serious threat to tomato production worldwide as it can cause important yield losses. Its control is currently mainly based on the use of synthetic chemical insecticides, which unfortunately selects resistant populations and entails public health risks. The aim of this study was to evaluate the insecticidal, repellent and sublethal effects of Carapa procera seed oil on all stages of T. absoluta. Larvicidal (by contact and by ingestion), ovicidal and anti-feeding effects were evaluated by testing 1.5%, 3%, 4.5%, 6% and 7.5% concentrations of oil. Larvicidal and ovicidal effects were tested by direct application of Carapa solutions on larvae and eggs but also by feeding the larvae leaves dipped in solutions. The adult repellent effect was investigated by identifying the preferred area on filter paper partly non-treated versus fully treated using LC10, LC50 et LC90 of larvae after ingestion. LC50 was also used on 2-day-old larvae to evaluate the sublethal effects on larval and pupal duration, longevity and adult morphology. Results showed that, regardless of the mode of application, all concentrations had larvicidal effects with a higher dose-response effect and a higher mortality rate via ingestion than via topical application. The ovicidal effect varied with the concentrations tested, the highest mortality rate was obtained at a concentration of 7.5%. At the same dose, Carapa oil reduced large feeding galleries from 92.22 ± 5.02% in controls to 3.33 ± 3.65% at the highest dose and had a repellent effect on 80% of adults. Carapa oil increased larval and pupal duration by 2.14 and 1.35 days, respectively, and reduced adult female longevity by 2.2 days and male longevity by 1.1 days. A deformation rate of 28.33% was observed in newly emerged adults. This study demonstrated insecticidal and insect repellent effects of Carapa oil on different stages of T. absoluta. This botanical oil is a very promising biopesticide to control this major new pest of Solanaceous crops. Its use in an agroecological pest management strategy is discussed.
PubDate: 2023-12-01
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- Toxicity effects of several medicinal plants essential oils on Angoumois
grain moth (Sitotroga cerealella) female adults-
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Abstract: Abstract The use of plant essential oils as eco-friendly and bio-rational insecticides have emerged as a promising alternative to hazardous fumigant pesticides for controlling stored product insect pests. This study investigated the vapor toxicity of essential oils obtained from Thymus vulgaris, Satureja hortensis, Pelargonium roseum, and Syzygium aromaticum against Sitotroga cerealella (Olivier) female adults. Gas chromatography–mass spectrometry analysis revealed Thymol (56.36%), Citronellol (39.7%), Eugenol (80.0%), and Carvacrol (42.28%) as the primary components in T. vulgaris, P. roseum, S. aromaticum, and S. hortensis, respectively. Probit analysis determined the 24-h toxicity of the essential oils diluted in acetone (10%), resulting in LC50 values of 20.125, 14.193, 14.189, and 13.562 μgL-1(air) for T. vulgaris, P. roseum, S. aromaticum, and S. hortensis, respectively. Additionally, sublethal effects were observed at LC25 during the first generation. The treatments significantly impacted oviposition, egg hatchability, survival rate of larvae-pupae, and egg duration, leading to decreased values in these parameters. The essential oils derived from these four plant species demonstrate remarkable potential in the management of S. cerealella. Their vapor toxicity and sublethal effects on female adults underscore their effectiveness as sustainable tools within integrated pest management strategies for stored product pest control.
PubDate: 2023-12-01
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- Determination of fumigant toxicity of single, binary and tertiary mixtures
of three essential oils against Frankliniella occidentalis Pergande
(Thysanoptera: Thripidae)-
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Abstract: Abstract In this study, three essential oils extracted from sage (Salvia officinalis L.), thyme (Thymus vulgaris L.) and daphne (Laurus nobilis L.) were used individually against the adult Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) pest. Afterward, the fumigant toxicity of binary (1:1) and tertiary (1:1:1) mixtures was investigated under laboratory conditions. The results showed that all essential oils tested, both alone and in all binary and tertiary mixtures, had fumigant toxicity on adult F. occidentalis. Mortality rates of 3–5-day-old adults of F. occidentalis increased with increasing concentration from 2 to 10 µL/L. In the entire study, binary and tertiary mixtures of the oils were more successful than the individual application. At a dose of 10 µL/L, all binary and tertiary mixtures of the oils caused 100% mortality at all exposure times. However, when sage oil was fumigated for 24 h and applied alone, the mortality rate was less than 100%. Moreover, the highest synergistic effect was found in tertiary essential oil mixtures (sage + daphne + thyme) with 10.0 µL/L air LC50 value in all application doses, counted after 48 h. Our overall results show that binary and tertiary mixtures of all tested essential oils are promising candidates for protection against western flower thrips.
PubDate: 2023-12-01
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- Artificially applied late-terminal drought stress in the field
differentially affects Ramularia leaf spot disease in winter barley-
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Abstract: Ramularia leaf spot disease (RLS) is one of the most dominating fungal diseases in barley. The disease typically appears late in the season after flowering and results in a rapid loss of photosynthetic leaf area. A recent decline in fungicide efficacy and a lack of RLS-resistant cultivars hamper effective control. Global warming will provoke increasing droughts which influence host plant physiology and probably affect outbreak and severity of RLS. Relatively little is known about genetic resistance to RLS in winter barley and about the influence of various weather conditions and climate change on RLS pathogenesis. Hence, we evaluated severity of RLS on 15 winter barley genotypes under persistent late-terminal drought stress or controlled irrigation, respectively, in a field rainout shelter. Over three consecutive years, we observed reproducible differences in quantitative RLS field resistance of the used cultivars and variable suppression of RLS under drought. Our results support a function of drought in suppression of RLS in winter barley, but also reveal strong year effects even under semi-controlled rainout shelter conditions. Data may be relevant for genotype selection in breeding programmes for RLS resistance and for farmers in the frame of integrated disease management under a changing climate. Graphical abstract
PubDate: 2023-12-01
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- Occurrence and distribution of Grapevine pinot gris virus and other
grapevine viruses in German viticultural regions-
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Abstract: Abstract To determine the occurrence and distribution of prevalent viruses in commercially important vineyards, a survey was carried out in all thirteen wine-growing regions in Germany. Results reveal that the recently emerged Grapevine pinot gris virus (GPGV) was the most abundant virus with a percentage of 18% prevalence, followed by 13% Grapevine fleck virus (GFkV), 9% Grapevine leafroll-associated virus 1 (GLRaV-1), 4% Grapevine fanleaf virus (GFLV), 2% Raspberry ringspot virus (RpRSV), 2% Arabis mosaic virus (ArMV) and 2% Grapevine leafroll-associated virus 3 (GLRaV-3). Distribution of some viruses varies greatly between individual regions, thus regional hotspots or gradients were detected. GPGV for example is mostly found in southeastern Germany, while its incidence decreases to the north along the river Rhine. The findings of this survey provide an overview of the allocation of the most prevalent grapevine viruses in Germany and can support regional virus management and national risk assessment especially GPGV.
PubDate: 2023-12-01
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- Susceptibility of South American pear cultivars to brown spot of pear
caused by Stemphylium vesicarium-
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Abstract: Abstract Brown spot of pear (BSP), a fungal disease, was recently detected in the Alto Valle of Río Negro region in Patagonia, Argentina. BSP is caused by Stemphylium vesicarium (teleomorph: Pleospora herbarum, syn. P. allii) in its sexual and asexual stages, and its main symptoms are lesions in fruit and leaves. The aim of the present study was to characterize the susceptibility of four main pear cultivars grown in the Alto Valle of Río Negro to infection by S. vesicarium. Over four recent growing seasons, BSP incidence and severity were monitored in an orchard with ‘Williams’, ‘Packham’s’, ‘D'Anjou’, and ‘Abate Fetel’ pear cultivars. In addition, inoculations of a pathogenic S. vesicarium strain were performed on detached fruit and leaves of the four cultivars. Both in-field observations and in vitro inoculation experiments indicated that fruit and leaf susceptibility to BSP was markedly higher in ‘D'Anjou’ and ‘Abate Fetel’ compared to ‘Packham’s’ and ‘Williams’. These findings provide valuable information for the correct allocation of resources to efficiently monitor and control BSP.
PubDate: 2023-12-01
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- Isolation and identification of grapevine endophytic bacteria with
antagonistic potential against Fomitiporia mediterranea, a pathogen
involved in grapevine trunk disease-
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Abstract: Background Grapevine trunk diseases (GTDs) are an economically serious threat, affecting grapevine long-term sustainability and productivity. The use of antagonistic endophytic bacteria can be a promissing approach for GTDs’ management. Results 253 bacterial endophytes were isolated from the stems and roots of grapevines from 68 geographic locations in eight provinces of Iran. Based on biochemical properties, 22 strains were selected and identified using the 16S rRNA gene. The representative strains belonged to 13 genera of Agrobacterium, Arthrobacter, Bacillus, Chryseobacterium, Klebsiella, Kocuria, Pantoea, Pseudomonas, Rahnella, Rothia, Serratia, Staphylococcus and Variovorax. Using the dual culture method, antagonistic activity of 27 strains from 50 selected ones was shown against Fomitiporia mediterranea, a pathogen of GTDs; in which its hyphal growth was inhibited from 10 to 55%. Among the tested bacteria, Serratia plymuthica GI154, Bacillus sp. GI298 and Pseudomonas fluorescens GI310 showed the highest fungal growth inhibition zones, respectively. Co-treatment of GI154, GI298, and GI310 with F. mediterranea, in planta, could reduce the length of its internal canker by 54.41, 60.16 and 49.42% in compare with contol, respectively. Conclusions To the best of our knowledge, this is the first report of isolation of Arthrobacter agilis, Chryseobacterium daecheongense, Rahnella aquatilis, Serratia plymuthica, Staphylococcus epidermidis, Staphylococcus warneri and Variovorax paradoxus from grapevine in Iran. Moreover, this is the first report of Rothia amarae as a bacterial endophyte of the grapevine for the world. Grapevine bacterial endophytes exhibit auspicious biocontrol activities that can be utilized in sustainable and organic agriculture.
PubDate: 2023-12-01
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- Comparative biological parameters of the predatory mites, Amblyseius
swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) on the
invasive pest Eutetranychus orientalis (Klein)-
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Abstract: Abstract The aim of this study was to evaluate the biological features and life table parameters of Amblyseius swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) collected from the same citrus ecosystem, on Eutetranychus orientalis (Klein) under laboratory conditions (25 °C and 70 ± 5% RH). Results revealed that total mean developmental times of A. swirskii and E. scutalis were 7.24 and 7.45 days for females, and 6.54 and 7.02 days for males, respectively. The preoviposition, oviposition, postoviposition periods and total adult longevity of predatory mite species were 2.41, 20.93, 2.57 and 25.92 days for A. swirskii and 2.34, 20.23, 2.58 and 25.15 days for E. scutalis, respectively. Daily (oviposition) and total mean numbers of eggs laid by A. swirskii were 2.09 and 43.16, by E. scutalis were 1.59 and 31.85, respectively. The intrinsic rate of increase (rm), net reproduction rate (Ro) and mean generation time (To) were 0.219, 28.65 and 15.28 days for A. swirskii, and 0.189, 21.18 and 6.15 days for E. scutalis, respectively. In general, biological parameters of A. swirskii were better than those of E. scutalis when fed on E. orientalis. It was concluded that both predatory mite species A. swirskii and E. scutalis could complement each other in controlling the target pest E. orientalis in citrus ecosystem.
PubDate: 2023-12-01
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- Synergized toxicity exhibited by indigenous entomopathogenic fungal
strains, plant extracts and synthetic insecticides against fall armyworm
Spodoptera frugiperda (J.E. Smith) under laboratory and semi-field
conditions-
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Abstract: Abstract The fall armyworm, Spodoptera frugiperda (J.E. Smith), is a destructive transboundary lepidopterous pest affecting more than 78 countries worldwide by infesting a wide array of agronomic and horticultural crops such as maize and cabbage. In a previous study, we demonstrated the synergized toxicity of three local plant extracts (Rhazya stricta Decne., Sophora mollis (Royle) Baker and Withania somnifera (L.) Dunal) with synthetic insecticide chlorantraniliprole against 3rd instar larvae of S. frugiperda. Here we evaluated the combined efficacy of indigenous entomopathogenic fungi (EPF) (Beauveria bassiana (Balsam) Vuillemin and Metarhizium anisopliae (Metschn.) Sorokin) along with above-mentioned plant extracts and chlorantraniliprole against 3rd instar larvae of S. frugiperda under laboratory and semi-field conditions. Toxicity bioassays with two EPF revealed that the highest concentration (1.0 × 109 conidia per mL) of B. bassiana caused maximum larval mortality (76%) at 10th day post-treatment, followed by M. anisopliae, causing 70% larval mortality at the same concentration. In vitro evaluation of six binary combinations of LC33s of EPF (B. bassiana and M. anisopliae) and plant extracts revealed a synergized toxicity (83–87%) of four combinations comprising S. mollis and W. somnifera with B. bassiana and M. anisopliae against 3rd instar S. frugiperda larvae. Furthermore, these insecticidal combinations including chlorantraniliprole (@ half of the label-recommended dose) exhibited as well a significant synergized toxicity (i.e. 37.75% at 1st day to 99.25% at 7th day post-treatment) under semi-field conditions, suggesting their further investigation under field against S. frugiperda and on its natural enemies.
PubDate: 2023-12-01
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- A rapid visual detection method for Potato virus Y based on loop mediated
isothermal amplification (LAMP)-
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Abstract: Abstract In order to establish a rapid and sensitive LAMP visual detection method for Potato virus Y on-site, this study used the conserved fragment of PVY CP gene sequence as a template to design primers, and the rapid visual LAMP detection method of Potato virus Y was successfully established by optimizing the reaction system components (concentration ratio of internal and external primers, and concentrations of loop primers, Bst DNA, Mg2+, dNTP and betaine) and reaction conditions (temperature). The established rapid visual LAMP detection method for Potato virus Y can specifically identify Potato virus Y, providing complete visual detection within 40 min, and the detection limit can reach 4.34 pg μL−1 (cDNA) concentration, which is 100 times more sensitive than PCR. An analysis of 50 potato field samples showed that the results of rapid visualization LAMP and RT-PCR were basically the same. This method is suitable for the rapid detection of Potato virus Y on-site, and this study can also provide theoretical reference for the early diagnosis of other potato viruses.
PubDate: 2023-12-01
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- Field testing of a new-designed light trap for mass-trapping of May–June
beetles (Coleoptera: Scarabaeidae) in horticultural areas-
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Abstract: White grubs, the immature forms of the well-known May–June beetles (Coleoptera: Scarabaeidae), are the most wide spread and destructive insect pests of many agricultural crops worldwide. White grub management in Turkey relies heavily on soil application of synthetic insecticides, with negative side effects on soil organisms. In this study, a new-designed light trap (so-called ecosav-Mns1) was evaluated for mass-trapping of adult May–June beetles in a heavy infested apple orchard located in Isparta province (in southwestern part of Turkey) during the flight period from May to September in two successive years (2020 and 2021). The trap was tested at a density of 2 traps/decare in both years. The captured beetles were counted at weekly intervals during a four-month sampling period in both years, and the efficiency of the trap was evaluated on the basis of weekly mean numbers per trap in both years. The results indicated that very high numbers of beetles were captured in the traps especially in the first year of study (118.2 adults/trap/week in 2020). The newly designed light trap captured both males and females of both species; however, in both 2020 and 2021, more males were caught in the traps. The results also showed that mass-trapping of adult May–June beetles using newly designed light trap had a pronounced effect on their subsequent larval (white grub) populations. For instance, while mean number of larvae found in the soil around the root system was 9.8/tree in May in the first year of the study, it was 3.3/tree in the same month in the second year. All the results suggested that the new-designed light trap may help prevent the root damage caused by white grubs in horticultural areas by trapping adults of May–June beetles effectively. Graphical abstract This study demonstrated that the new-designed light trap (ecosav-Mns1) may help prevent the root damage caused by white grubs in horticultural areas by trapping adults of May–June beetles effectively.
PubDate: 2023-12-01
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- Maize protection against Bipolaris maydis using Lentinula edodes, Aloe
vera and acibenzolar-S-methyl-
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Abstract: Abstract Maize (Zea mays) is the most commonly produced grain worldwide. One of the factors that can lead to a decrease in productivity is the Southern Leaf Blight caused by Bipolaris maydis. This is common in the main producing regions and can promote losses of up to 70% under suitable conditions. A few genotypes are resistant to this fungus, and there is no record of fungicides for the disease in Brazil. In order to search for alternative control measures with lower environmental impacts, the objective of this study was to investigate the use of polysaccharide fractions extracted from shiitake or aloe, as well as acibenzolar-S-methyl (ASM), as potential inductors of resistance in maize against B. maydis. Tests were conducted with maize plants (hybrids P1630H and BM3063) to evaluate the effects of the products on reducing disease severity, inhibiting pathogen germination and activating guaiacol peroxidase and phenylalanine ammonia-lyase (PAL) activities. Aloe and ASM were not efficient to control the disease. Fraction PS1 from shiitake reduced the disease severity in both hybrids by approximately 60%. Meanwhile, fraction PS2 was efficient only in hybrid BM3063, where it promoted an increase in PAL activity. However, these fractions did not affect the spore germination of B. maydis. Therefore, the polysaccharide fractions from shiitake have the potential to control Southern Leaf Blight (B. maydis) in maize probably through the activation of plant defense mechanisms.
PubDate: 2023-12-01
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- Analysis of Fall armyworm infestations on rainy season crops under
different cropping systems in two agroecological zones in Burkina Faso,
West Africa-
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Abstract: Abstract The Fall armyworm (FAW), Spodoptera frugiperda, was first reported in a few regions of Burkina Faso in 2017. Since then, it has continued to spread and damage maize crops in the country, thereby threatening food security. This study, conducted three years later, aimed to assess the pest status on major rainy season crops, and the effects of cropping systems, crop diversity, and phenology in 11 localities of Sudanian and Sudano-Sahelian zones in Burkina Faso. Two sampling periods, the first conducted at the beginning of the rainy season and the second at the end of the season, were considered. Maize was the most FAW-infested crop, mainly as monocrops (84–88% of surveyed fields). Sorghum, pearl millet, cowpeas, and peanuts were the secondary infested crops, more infested when intercropped with maize. Maize fields were more FAW-affected in the Sudanian zone, whereas the secondary infested crops were significantly more affected in the Sudano-Sahelian zone. The highest field infestation rates were recorded during the second survey period, coinciding in most cases (> 90%) with the flowering and post-flowering of maize. Then, FAW attacks were found in vegetative, flowering, and post-flowering cereal organs. Despite the technical recommendations, most farmers (57.30 ± 10.34 and 66.78 ± 6.74% in the Sudanian and Sudano-Sahelian zones, respectively) did not apply insecticide in infested maize fields. Thus, in 3 years, the FAW has become an important pest of cereals, specifically maize, in the main agricultural zones of Burkina Faso. These results should be taken into account to develop effective control actions against FAW.
PubDate: 2023-12-01
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- Chemical composition, antioxidant, herbicidal and antifungal activities of
leaf essential oils from three Tunisian Eucalyptus species-
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Abstract: Abstract Medicinal plants produce several natural bioactive molecules and compounds called secondary metabolites that have very important biological properties. The objective of this work is to determine the chemical composition of essential oils (EO) obtained from the leaves of three Tunisian species of Eucalyptus (E. oleosa, E. pimpiniana, E. polyanthemos) and to evaluate their biological activities. As a result, 45 different compounds were identified: 26 from E. pimpiniana, 15 from E. polyanthemos, and 39 from E. oleosa, which represent 99.4%, 99.4% and 98.6%, respectively, of the entire essential oil constituents. The analyses showed that 1,8-cineole (35.3%) and β-eudesmol (25.5%) were the main components in E. pimpiniana essential oil, whereas 1,8-cineole (71.6%) and globulol (13.2%) characterized E. polyanthemos leaf oil. Also, 1,8-cineole (13.4%), spathulenol (11.9%), and β-eudesmol (8.5%) were found to be the main constituents of E. oleosa EO. Other compounds, such as phellandral, p-cymen-7-ol (syn. cumin alcohol), carvacrol, myrtenal, cumin aldehyde and cryptone, are specific to the EOs of E. oleosa, making it distinct from the other Eucalyptus species studied. The essential oils showed low antioxidant capacity, but significant antifungal activity against five Fusarium spp. Indeed, E. oleosa essential oil exhibited the highest level of antifungal activity. Additionally, herbicidal activity has only been proved in a preliminary in vitro test against 3 weed species (Sinapis arvensis L., and Lepidium sativum) of the same family. The greatest inhibition of seed germination was obtained with the E. oleosa essential oils even at low concentrations strongly suggesting that they could have application in agriculture, particularly as antagonists against Fusarium and other fungi and for weed control.
PubDate: 2023-12-01
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- The invasive fall armyworm, Spodoptera frugiperda, in Africa and Asia:
responding to the food security challenge, with priorities for integrated
pest management research-
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Abstract: Abstract In sub-Saharan Africa (SSA) and several Asian countries, maize continues to be a major staple food for millions of people. It plays an important role in food and nutrition security and as a source of income. Pests and diseases, however, are the primary biotic constraints to maize productivity in these countries. The recent invasion of the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), throughout Africa and Asia threatens the production and food security goals of subsistence smallholder farmers throughout most of sub-Saharan Africa followed by spread to India in 2018 and China. FAW was first detected in West Africa from São Tomé, Nigeria, Bénin and Togo in early 2016. As of May 2019, FAW has now been confirmed in all sub-Saharan countries, and later on its occurrence has been reported in various Asian countries. FAW is a highly polyphagous pest attacking over 350 plant species, including several economically important crops such as maize (Zea mays L.), rice (Oryza sativa L.), cotton (Gossypium spp. L.), sorghum (Sorghum bicolor (L.) Moench) and several legumes that are also preferred hosts. In Africa, without effective FAW management options, this pest will cause substantial maize yield losses ranging from 8.3 to 20.6 million tonnes annually, with losses of $2.5–6.2 million. However, now that FAW is established in > 42 countries, the total annual impact is estimated at $13 billion. Although over 150 species of FAW parasitoids have been recorded in the Americas, there is still the demand of information regarding the potential of biological control in Africa, and alternative complementary management tactics. Given the ongoing damage potential of FAW in Africa, and now Asia, the urgency to develop practical management solutions at the farm level cannot be overemphasized. This review summarizes much of the global, current research that should be useful in developing FAW management programs for smallholder farmers in SSA and Asia. In so doing, we present an Integrated pest management (IPM) framework that relies on several foundational and compatible tactics, including timely monitoring of FAW, host plant resistance, biological control, cultural control, and when necessary, chemical control. Consequently, this review identifies several research gaps, as well as logical research objectives that should prove useful going forward. Finally, we explore how sustainable IPM systems for FAW can contribute to both long-term food security and environmental stewardship goals for agricultural production in sub-Saharan Africa and Asia-Pacific region.
PubDate: 2023-12-01
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- An integrated machine learning-based virtual screening strategy for
biological weeding in maize field: a case study with HPPD-
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Abstract: Abstract The habitancy of maize crops endorses a broad spectrum of post-emergence weeds. Of note, 4-hydroxyphenylpyruvate dioxygenase (HPPD) is regarded as a promising herbicidal target due to its crop selectivity. Despite the use of several machine learning (ML) techniques to discriminate herbicides from decoys, no studies have reported an ML-based virtual screening (VS) strategy for screening potential hits against key targets towards weed management. Thus, we built an in-house ML model using a dataset of 603 herbicides from PADFrag and Gandy databases and 603 decoys. Of note, PaDEL software was utilized to generate the molecular descriptors and fingerprints of the compounds. The eXtreme Gradient Boosting (XGB) classifier outperformed other models with 96% accuracy. Therefore, we opted XGB model to predict the possible herbicides from the Toxic Plants-PhytoToxins (TPPT) database and subjected them to a series of VS techniques. This process spotted that CNP0195529 (ginkgoic acid) formed π–π stacking with HPPD HIS308 residue, similar to the benquitrione (reference) compound. Note that, the existence of hydroxybenzoic acid moiety in ginkgoic acid likely to be the reason for its extensive weed-suppressing activity. Adding together, the docking score (− 7.151 kcal/mol), MM/GBSA (− 82.62 kcal/mol), and random forest (RF) score (+ 6.054 pKa) of ginkgoic acid signify the favourable binding against HPPD. The dynamic behaviour of the HPPD–ginkgoic acid system increases the credibility of our findings. Collectively, we believed that our hit compound ginkgoic acid could serve as a promising HPPD inhibitor in the maize field.
PubDate: 2023-12-01
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