Pub Date : 2026-04-01Epub Date: 2026-01-02DOI: 10.1016/j.cropro.2025.107527
Shi-Qi Guo , Chada Norphanphoun , Fatimah Al-Otibi , Kevin D. Hyde , Juan Liu , Hong-Mei Liu , Wen-E Zhang , Yong Wang
Rhododendron is an important ornamental crop in Guizhou Province, China, where intensified cultivation has led to increasing disease problems. In this study, a leaf spot disease was investigated on Rhododendron in the Baili Forest Region. The disease initially appeared as brown, circular to irregular lesions, which gradually enlarged, turned dark brown, and developed lighter margins with visible signs of wilting and decay. Severe infection led to premature leaf death, thereby compromising plant vigor. Field surveys of 200 Rhododendron hybridum leaves revealed 66 symptomatic samples, corresponding to a disease incidence of 33 %, which has caused notable economic losses to local horticultural operations. Morphological examination, together with multi-gene phylogenetic analysis (ITS, tef1-α, and β-tubulin), identified the causal agent as Neopestalotiopsis maddoxii. Pathogenicity was confirmed by artificial inoculation, which reproduced typical symptoms and fulfilled Koch's postulates. This is the first report of N. maddoxii causing leaf spot on Rhododendron in Guizhou Province, providing a basis for future studies on its epidemiology and management.
{"title":"Leaf spot of Rhododendron hybridum caused by Neopestalotiopsis maddoxii in China","authors":"Shi-Qi Guo , Chada Norphanphoun , Fatimah Al-Otibi , Kevin D. Hyde , Juan Liu , Hong-Mei Liu , Wen-E Zhang , Yong Wang","doi":"10.1016/j.cropro.2025.107527","DOIUrl":"10.1016/j.cropro.2025.107527","url":null,"abstract":"<div><div><em>Rhododendron</em> is an important ornamental crop in Guizhou Province, China, where intensified cultivation has led to increasing disease problems. In this study, a leaf spot disease was investigated on <em>Rhododendron</em> in the Baili Forest Region. The disease initially appeared as brown, circular to irregular lesions, which gradually enlarged, turned dark brown, and developed lighter margins with visible signs of wilting and decay. Severe infection led to premature leaf death, thereby compromising plant vigor. Field surveys of 200 <em>Rhododendron hybridum</em> leaves revealed 66 symptomatic samples, corresponding to a disease incidence of 33 %, which has caused notable economic losses to local horticultural operations. Morphological examination, together with multi-gene phylogenetic analysis (ITS, <em>tef1-α</em>, and <em>β-tubulin</em>), identified the causal agent as <em>Neopestalotiopsis maddoxii</em>. Pathogenicity was confirmed by artificial inoculation, which reproduced typical symptoms and fulfilled Koch's postulates. This is the first report of <em>N. maddoxii</em> causing leaf spot on <em>Rhododendron</em> in Guizhou Province, providing a basis for future studies on its epidemiology and management.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107527"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145893700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-16DOI: 10.1016/j.cropro.2025.107526
Weronika Giedrojć , Wioletta E. Pluskota , Urszula Wachowska
Powdery mildew (PM) caused by Blumeria graminis and Septoria tritici blotch (STB) caused by Zymoseptoria tritici are common and devastating diseases of durum wheat. The aim of this study was to analyze the effect of fungicides and a Debaryomyces hansenii yeast strain (a biological control agent, BCA) on pathogens and the mycobiome of durum wheat grain. The experiment was conducted on naturally infected plants. The effectiveness of BCA was tested alone by applying three protective treatments in the stem elongation, heading, and flowering stages. In the integrated approach, BCA was applied after fungicide treatment (proquinazid, prothioconazole, and spiroxamine) in the stem elongation stage.Unprotected plants (control) and plants protected with one or two fungicide treatments were used as reference materials. The severity of leaf, spike, and grain diseases, and grain colonization by fungi were evaluated using phytopathological and mycological methods. The number of fungal operational taxonomic units (OTUs) was determined by next-generation sequencing (NGS). In both years of the experiment, fungicides applied in the stem elongation stage (proquinazid, prothioconazole, and spiroxamine) and the heading stage (prothioconazole and tebuconazole), and BCA treatments applied three times reduced the prevalence of STB (by 55.56 % and 35.45 %, respectively) and the percentage of kernels with symptoms of infection (by 44.69 % and 36.46 %, respectively) relative to unprotected plants. Integrated fungicide and biological treatments (Integ) inhibited STB by 47.62 %, but the percentage of infected kernels was only 24.71 % lower than in the control treatment. When the first fungicide treatment was not applied (Fung 2), the effectiveness of protection against Z. tritici decreased in the second year of the study. Grain treated with BCA was colonized predominantly by D. hansenii, which reduced the number of OTUs of biotrophic (including Blumeria graminis) and necrotrophic pathogens (including F. avenaceum). The study demonstrated that the integration of fungicides with biological yeast treatments applied in the flowering stage is a promising approach to controlling diseases in organically grown durum wheat.
{"title":"Effect of fungicides and the biological control agent Debaryomyces hansenii on pathogens and the mycobiome of durum wheat grain under drought conditions","authors":"Weronika Giedrojć , Wioletta E. Pluskota , Urszula Wachowska","doi":"10.1016/j.cropro.2025.107526","DOIUrl":"10.1016/j.cropro.2025.107526","url":null,"abstract":"<div><div>Powdery mildew (PM) caused by <em>Blumeria graminis</em> and Septoria tritici blotch (STB) caused by <em>Zymoseptoria tritici</em> are common and devastating diseases of durum wheat. The aim of this study was to analyze the effect of fungicides and a <em>Debaryomyces hansenii</em> yeast strain (a biological control agent, BCA) on pathogens and the mycobiome of durum wheat grain. The experiment was conducted on naturally infected plants. The effectiveness of BCA was tested alone by applying three protective treatments in the stem elongation, heading, and flowering stages. In the integrated approach, BCA was applied after fungicide treatment (proquinazid, prothioconazole, and spiroxamine) in the stem elongation stage.Unprotected plants (control) and plants protected with one or two fungicide treatments were used as reference materials. The severity of leaf, spike, and grain diseases, and grain colonization by fungi were evaluated using phytopathological and mycological methods. The number of fungal operational taxonomic units (OTUs) was determined by next-generation sequencing (NGS). In both years of the experiment, fungicides applied in the stem elongation stage (proquinazid, prothioconazole, and spiroxamine) and the heading stage (prothioconazole and tebuconazole), and BCA treatments applied three times reduced the prevalence of STB (by 55.56 % and 35.45 %, respectively) and the percentage of kernels with symptoms of infection (by 44.69 % and 36.46 %, respectively) relative to unprotected plants. Integrated fungicide and biological treatments (Integ) inhibited STB by 47.62 %, but the percentage of infected kernels was only 24.71 % lower than in the control treatment. When the first fungicide treatment was not applied (Fung 2), the effectiveness of protection against <em>Z. tritici</em> decreased in the second year of the study. Grain treated with BCA was colonized predominantly by <em>D. hansenii,</em> which reduced the number of OTUs of biotrophic (including <em>Blumeria graminis</em>) and necrotrophic pathogens (including <em>F. avenaceum</em>). The study demonstrated that the integration of fungicides with biological yeast treatments applied in the flowering stage is a promising approach to controlling diseases in organically grown durum wheat.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107526"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145995805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2025-12-17DOI: 10.1016/j.cropro.2025.107523
Javier Godoy-Güinao , Sonia B. Canavelli , Marcela Márquez-García , Eduardo A. Silva-Rodríguez
The economic impact of crop damage caused by wildlife can be perceived as significant by producers. Consequently, producers adopt different management strategies, which can affect the populations of the species involved. However, it is generally unknown whether producers’ damage estimates reflect actual losses, fostering conflicts between producers and conservationists. The objective of our study was to evaluate the association between damage caused by wildlife and damage perceived by producers, using interactions between native parakeets (Enicognathus spp.) and forage maize crops in southern Chile as a study model. Perceived damage was measured using a structured questionnaire, and actual losses were estimated in the field determining the percentage of plants damaged by parakeets. Producers reported that most paddocks (>80 %) did not experience losses caused by parakeets. Similarly, field measurements indicated that most paddocks (88.5 %) had damage below 5 % of the sown area. Significant losses (>5 %) were detected in 11.5 % of the paddocks. Comparing perceived and actual damage, producers underestimated damage in 62.3 % of paddocks and overestimated it in 14.8 %. Quantile regression showed that actual and perceived damage differed across levels of perceived damage. No significant association was observed at low levels, whereas at intermediate and high levels, perceived and actual losses were positively associated, with some producers underestimating and others overestimating damage as actual losses increased. Considering that perceived damage is positively associated with actual damage—especially at high levels of perceived damage— and that such damage can be severe, it is necessary to test management and financial alternatives that enable coexistence between agriculture and wildlife.
{"title":"Underestimating low and overestimating high parakeet damage: Linking crop losses and farmer perception","authors":"Javier Godoy-Güinao , Sonia B. Canavelli , Marcela Márquez-García , Eduardo A. Silva-Rodríguez","doi":"10.1016/j.cropro.2025.107523","DOIUrl":"10.1016/j.cropro.2025.107523","url":null,"abstract":"<div><div>The economic impact of crop damage caused by wildlife can be perceived as significant by producers. Consequently, producers adopt different management strategies, which can affect the populations of the species involved. However, it is generally unknown whether producers’ damage estimates reflect actual losses, fostering conflicts between producers and conservationists. The objective of our study was to evaluate the association between damage caused by wildlife and damage perceived by producers, using interactions between native parakeets (<em>Enicognathus</em> spp.) and forage maize crops in southern Chile as a study model. Perceived damage was measured using a structured questionnaire, and actual losses were estimated in the field determining the percentage of plants damaged by parakeets. Producers reported that most paddocks (>80 %) did not experience losses caused by parakeets. Similarly, field measurements indicated that most paddocks (88.5 %) had damage below 5 % of the sown area. Significant losses (>5 %) were detected in 11.5 % of the paddocks. Comparing perceived and actual damage, producers underestimated damage in 62.3 % of paddocks and overestimated it in 14.8 %. Quantile regression showed that actual and perceived damage differed across levels of perceived damage. No significant association was observed at low levels, whereas at intermediate and high levels, perceived and actual losses were positively associated, with some producers underestimating and others overestimating damage as actual losses increased. Considering that perceived damage is positively associated with actual damage—especially at high levels of perceived damage— and that such damage can be severe, it is necessary to test management and financial alternatives that enable coexistence between agriculture and wildlife.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107523"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145786043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-14DOI: 10.1016/j.cropro.2026.107543
Nathan S. Little, Ryan T. Paulk, Blake H. Elkins, R. Michelle Mullen, K. Clint Allen
The bollworm (Helicoverpa zea), a persistent pest of U.S. cotton, poses ongoing challenges to producers. Transgenic cotton expressing Bacillus thuringiensis (Bt) insecticidal proteins has revolutionized bollworm control while reducing reliance on broad-spectrum insecticides. However, variability in toxin expression across plant structures and developmental stages may reduce efficacy and contribute to the development of resistance. This study evaluates the relative expression of Cry1Ac, Cry2Ab, and Vip3A proteins in two Bt cotton cultivars throughout the growing season and compares these data with bollworm larval mortality on fruiting structures. Our results show a general decline in Cry1Ac and Cry2Ab levels throughout the growing season, while Vip3A expression remained relatively stable. Bollworm larval mortality was highest in squares, followed by blooms and bolls. Bollgard II cotton exhibited higher early-season Cry1Ac levels than the Bollgard III variety, potentially influencing early-season pest suppression. Vip3A expression was the highest in blooms of Bollgard III cotton, followed by squares and bolls. These findings underscore the importance of mid-to late-season scouting for surviving larvae on blooms and boll damage in Bt cotton. A better understanding of the spatiotemporal expression of Vip3A, coupled with preemptive resistance screening, will be vital for preserving Bt cotton's longevity and maintaining its role in sustainable production systems.
{"title":"Impact of crystalline and vegetative protein expression in dual- and multi-gene transgenic cottons on bollworm larval survival","authors":"Nathan S. Little, Ryan T. Paulk, Blake H. Elkins, R. Michelle Mullen, K. Clint Allen","doi":"10.1016/j.cropro.2026.107543","DOIUrl":"10.1016/j.cropro.2026.107543","url":null,"abstract":"<div><div>The bollworm (<em>Helicoverpa zea</em>), a persistent pest of U.S. cotton, poses ongoing challenges to producers. Transgenic cotton expressing <em>Bacillus thuringiensis</em> (Bt) insecticidal proteins has revolutionized bollworm control while reducing reliance on broad-spectrum insecticides. However, variability in toxin expression across plant structures and developmental stages may reduce efficacy and contribute to the development of resistance. This study evaluates the relative expression of Cry1Ac, Cry2Ab, and Vip3A proteins in two Bt cotton cultivars throughout the growing season and compares these data with bollworm larval mortality on fruiting structures. Our results show a general decline in Cry1Ac and Cry2Ab levels throughout the growing season, while Vip3A expression remained relatively stable. Bollworm larval mortality was highest in squares, followed by blooms and bolls. Bollgard II cotton exhibited higher early-season Cry1Ac levels than the Bollgard III variety, potentially influencing early-season pest suppression. Vip3A expression was the highest in blooms of Bollgard III cotton, followed by squares and bolls. These findings underscore the importance of mid-to late-season scouting for surviving larvae on blooms and boll damage in Bt cotton. A better understanding of the spatiotemporal expression of Vip3A, coupled with preemptive resistance screening, will be vital for preserving Bt cotton's longevity and maintaining its role in sustainable production systems.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107543"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145972887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-21DOI: 10.1016/j.cropro.2026.107546
Jūratė Ramanauskienė, Roma Semaškienė, Akvilė Jonavičienė, Yuliia Kochiieru, Eimantas Venslovas, Karolina Lavrukaitė, Mohammad Almogdad, Aurimas Sabeckis
Fungal diseases represent a major threat to wheat, causing significant quantitative and qualitative grain yield losses. The use of fungicides is an important factor that provides a high level of disease control, helps increase crop yields, and ensures stability of production, but environmental and health risks necessitate foundational strategies for fungal disease management. One of them could be use of resistant cultivars. A field experiment was conducted over four growing seasons (2016–2019). Six spring wheat cultivars were evaluated to assess the effects of cultivar resistance on disease severity. Cultivar resistance significantly influenced disease outcomes: powdery mildew area under the disease progress curve (AUDPC) values ranged from 68.04 to 342.28, while tan spot ranged from 45.03 to 163.44. These results showed that the choice of less susceptible varieties could significantly reduce disease severity by 72.4–80.1 %. Fusarium head blight indexes (FHBi) ranged from 0.03 to 13.62 %, showing a 99.8 % difference between extreme cultivars. A moderate positive correlation (p < 0.01) was observed between the FHBi and the percentage of Fusarium-infected kernels (FIK), while FIK and deoxynivalenol (DON) contamination showed only weak correlation. The effectiveness of fungicides varied by cultivar, with sensitive cultivars showing higher yield responses (+24.6 %) than disease resistant cultivars (+13.5 %). These results demonstrate that strategic cultivar selection can substantially reduce disease impact while optimizing chemical inputs.
{"title":"Effects of spring wheat cultivar resistance on leaf and Fusarium head blight diseases and deoxynivalenol content in Lithuania","authors":"Jūratė Ramanauskienė, Roma Semaškienė, Akvilė Jonavičienė, Yuliia Kochiieru, Eimantas Venslovas, Karolina Lavrukaitė, Mohammad Almogdad, Aurimas Sabeckis","doi":"10.1016/j.cropro.2026.107546","DOIUrl":"10.1016/j.cropro.2026.107546","url":null,"abstract":"<div><div>Fungal diseases represent a major threat to wheat, causing significant quantitative and qualitative grain yield losses. The use of fungicides is an important factor that provides a high level of disease control, helps increase crop yields, and ensures stability of production, but environmental and health risks necessitate foundational strategies for fungal disease management. One of them could be use of resistant cultivars. A field experiment was conducted over four growing seasons (2016–2019). Six spring wheat cultivars were evaluated to assess the effects of cultivar resistance on disease severity. Cultivar resistance significantly influenced disease outcomes: powdery mildew area under the disease progress curve (AUDPC) values ranged from 68.04 to 342.28, while tan spot ranged from 45.03 to 163.44. These results showed that the choice of less susceptible varieties could significantly reduce disease severity by 72.4–80.1 %. Fusarium head blight indexes (FHBi) ranged from 0.03 to 13.62 %, showing a 99.8 % difference between extreme cultivars. A moderate positive correlation (p < 0.01) was observed between the FHBi and the percentage of Fusarium-infected kernels (FIK), while FIK and deoxynivalenol (DON) contamination showed only weak correlation. The effectiveness of fungicides varied by cultivar, with sensitive cultivars showing higher yield responses (+24.6 %) than disease resistant cultivars (+13.5 %). These results demonstrate that strategic cultivar selection can substantially reduce disease impact while optimizing chemical inputs.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107546"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2025-12-12DOI: 10.1016/j.cropro.2025.107521
Ahmed M. Saveer, Gundersen-Rindal Dawn, Aijun Zhang
The cotton seed bug (CSB), Oxycarenus hyalinipennis (Hemiptera: Oxycarenidae), globally emerging pest native to Africa, is a serious insect pest of cotton, posing a significant threat to crop yield and quality. Both nymphs and adults feed on developing cotton seeds. Volatile organic compounds (VOCs) are key mediators of behavioral responses in heteropteran insects, including CSB, influencing aggregation, mating, and oviposition. In this study, we evaluated the behavioral role of volatiles emitted from nymph exuviae of CSB. Using a combination of Y-tube olfactometer, dual-choice refuge, and dual-choice oviposition bioassays, we assessed the responses of different developmental stages and reproductive statuses to exuviae-associated VOCs. Our results showed that nymphs and mated females were significantly attracted to nymph exuviae VOCs, with nymphs showing >78% and mated females >73% preference in both the Y-tube and refuge assays, whereas unmated females and males (mated and unmated) exhibited no attraction or a slight aversion. Furthermore, gravid females preferentially oviposited on cotton seeds exposed to nymph exuviae VOCs, suggesting that these chemical cues signal suitable oviposition sites, optimizing the chances for the offspring survivorship. This study provides the first evidence that exuviae-associated VOCs in O. hyalinipennis serve as multifunctional semiochemicals, guiding both aggregation and reproductive behavior. These findings offer new insights into the chemical ecology of CSB and highlight potential avenues for semiochemical-based pest management strategies to control CSB population, including the development of attract-and-kill systems for use in integrated pest management (IPM) programs.
{"title":"Odors from nymphal exuviae attract nymphs and gravid females of the cotton seed bug, Oxycarenus hyalinipennis (Hemiptera: Oxycarenidae)","authors":"Ahmed M. Saveer, Gundersen-Rindal Dawn, Aijun Zhang","doi":"10.1016/j.cropro.2025.107521","DOIUrl":"10.1016/j.cropro.2025.107521","url":null,"abstract":"<div><div>The cotton seed bug (CSB), <em>Oxycarenus hyalinipennis</em> (Hemiptera: Oxycarenidae), globally emerging pest native to Africa, is a serious insect pest of cotton, posing a significant threat to crop yield and quality. Both nymphs and adults feed on developing cotton seeds. Volatile organic compounds (VOCs) are key mediators of behavioral responses in heteropteran insects, including CSB, influencing aggregation, mating, and oviposition. In this study, we evaluated the behavioral role of volatiles emitted from nymph exuviae of CSB. Using a combination of Y-tube olfactometer, dual-choice refuge, and dual-choice oviposition bioassays, we assessed the responses of different developmental stages and reproductive statuses to exuviae-associated VOCs. Our results showed that nymphs and mated females were significantly attracted to nymph exuviae VOCs, with nymphs showing >78% and mated females >73% preference in both the Y-tube and refuge assays, whereas unmated females and males (mated and unmated) exhibited no attraction or a slight aversion. Furthermore, gravid females preferentially oviposited on cotton seeds exposed to nymph exuviae VOCs, suggesting that these chemical cues signal suitable oviposition sites, optimizing the chances for the offspring survivorship. This study provides the first evidence that exuviae-associated VOCs in <em>O. hyalinipennis</em> serve as multifunctional semiochemicals, guiding both aggregation and reproductive behavior. These findings offer new insights into the chemical ecology of CSB and highlight potential avenues for semiochemical-based pest management strategies to control CSB population, including the development of attract-and-kill systems for use in integrated pest management (IPM) programs.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107521"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2025-12-30DOI: 10.1016/j.cropro.2025.107534
Pedaveeti Suma , D.N. Kambrekar , P.U. Krishnaraj , Y.P. Arun , V. Naveen , P. Harikrishnan , Suresh R. Jambagi
Lepidopteran pests such as Plutella xylostella, Spodoptera litura, and Spodoptera frugiperda cause severe yield losses worldwide, and their management is increasingly constrained by resistance development and environmental concerns associated with synthetic insecticides. Actinobacteria, particularly Streptomyces spp., are prolific producers of bioactive metabolites, many of which exhibit insecticidal properties. In this study, three actinobacterial isolates—Streptomyces hyderabadiensis, S. racemochromogenes, and S. xiaminensis were characterized for their insecticidal activity against second instar larvae of the above pests under laboratory and greenhouse conditions. Bioassays demonstrated significant larval mortality, ranging from 58 %to 68 % at 48 h post-treatment to 75 %−81 % at 72–96 h, with efficacy comparable to the reference insecticide (spinosad). Molecular identification based on 16S rDNA sequencing confirmed the identity of the isolates with 98–99 % similarity to reference strains. LC-MS analysis identified diverse insecticidal metabolites, including linoleic acid, farnesyl acetate, coumaroyl tyramine, huperzine A, delsemine A, 9-octadecenamide, and organophosphate esters, which act through multiple mechanisms such as acetylcholinesterase inhibition, juvenile hormone agonism, and disruption of cuticular and respiratory functions. All the tested actinobacterial strains showed equal efficacy across all three insect pests tested. These findings highlight the potential of actinobacterial metabolites as eco-friendly alternatives for lepidopteran pest management. Further exploration of their formulation and field applicability could contribute to the development of sustainable microbial biopesticides.
{"title":"Biochemical characterization of actinobacterial metabolites and their potential application in the management of selected lepidopteran pests","authors":"Pedaveeti Suma , D.N. Kambrekar , P.U. Krishnaraj , Y.P. Arun , V. Naveen , P. Harikrishnan , Suresh R. Jambagi","doi":"10.1016/j.cropro.2025.107534","DOIUrl":"10.1016/j.cropro.2025.107534","url":null,"abstract":"<div><div>Lepidopteran pests such as <em>Plutella xylostella</em>, <em>Spodoptera litura</em>, and <em>Spodoptera frugiperda</em> cause severe yield losses worldwide, and their management is increasingly constrained by resistance development and environmental concerns associated with synthetic insecticides. Actinobacteria, particularly <em>Streptomyces</em> spp., are prolific producers of bioactive metabolites, many of which exhibit insecticidal properties. In this study, three actinobacterial isolates—<em>Streptomyces hyderabadiensis</em>, <em>S. racemochromogenes</em>, and <em>S. xiaminensis</em> were characterized for their insecticidal activity against second instar larvae of the above pests under laboratory and greenhouse conditions. Bioassays demonstrated significant larval mortality, ranging from 58 %to 68 % at 48 h post-treatment to 75 %−81 % at 72–96 h, with efficacy comparable to the reference insecticide (spinosad). Molecular identification based on 16S rDNA sequencing confirmed the identity of the isolates with 98–99 % similarity to reference strains. LC-MS analysis identified diverse insecticidal metabolites, including linoleic acid, farnesyl acetate, coumaroyl tyramine, huperzine A, delsemine A, 9-octadecenamide, and organophosphate esters, which act through multiple mechanisms such as acetylcholinesterase inhibition, juvenile hormone agonism, and disruption of cuticular and respiratory functions. All the tested actinobacterial strains showed equal efficacy across all three insect pests tested. These findings highlight the potential of actinobacterial metabolites as eco-friendly alternatives for lepidopteran pest management. Further exploration of their formulation and field applicability could contribute to the development of sustainable microbial biopesticides.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107534"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145880110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2025-12-20DOI: 10.1016/j.cropro.2025.107525
Xianxiong Liu , Chengqing Yang , Maoxian Wang , Dengquan Liu , Zhen Su , Zhongshun Cai , Junyi Gao , Cheng Li , Fengquan Liu
Pseudostellaria heterophylla, a perennial herbaceous plant of the Caryophyllaceae family, is widely cultivated in China because of its economic and medicinal value. Recent observations in Huangping, Guizhou Province, revealed a prevalent leaf spot disease affecting P. heterophylla, leading to decreased yields. This study identified the fungal species responsible for leaf spot disease in P. heterophylla. Phytopathogenic fungi were isolated from the leaves using a tissue isolation method. The purified cultures were cultivated in potato dextrose agar medium, subjected to morphological and molecular biology analyses, and evaluated for pathogenicity. Isolates obtained exhibited the hallmark pathogenic symptoms in accordance with Koch's postulates. Based on the morphological and molecular phylogeny of multi-loci (internal transcribed spacer, RNA polymerase II beta subunit, and β-tubulin) sequence data, Epicoccum thailandicum was identified as the causal agent. This study represents the first report of E. thailandicum as a pathogenic fungus infecting the leaves of P. heterophylla.
{"title":"Epicoccum thailandicum causes leaf spot disease on Pseudostellaria heterophylla in China","authors":"Xianxiong Liu , Chengqing Yang , Maoxian Wang , Dengquan Liu , Zhen Su , Zhongshun Cai , Junyi Gao , Cheng Li , Fengquan Liu","doi":"10.1016/j.cropro.2025.107525","DOIUrl":"10.1016/j.cropro.2025.107525","url":null,"abstract":"<div><div><em>Pseudostellaria heterophylla,</em> a perennial herbaceous plant of the Caryophyllaceae family, is widely cultivated in China because of its economic and medicinal value. Recent observations in Huangping, Guizhou Province, revealed a prevalent leaf spot disease affecting <em>P. heterophylla</em>, leading to decreased yields. This study identified the fungal species responsible for leaf spot disease in <em>P. heterophylla</em>. Phytopathogenic fungi were isolated from the leaves using a tissue isolation method. The purified cultures were cultivated in potato dextrose agar medium, subjected to morphological and molecular biology analyses, and evaluated for pathogenicity. Isolates obtained exhibited the hallmark pathogenic symptoms in accordance with Koch's postulates. Based on the morphological and molecular phylogeny of multi-loci (internal transcribed spacer, RNA polymerase II beta subunit, and β-tubulin) sequence data, <em>Epicoccum thailandicum</em> was identified as the causal agent. This study represents the first report of <em>E. thailandicum</em> as a pathogenic fungus infecting the leaves of <em>P. heterophylla</em>.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107525"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145784823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2025-12-01DOI: 10.1016/j.cropro.2025.107514
Matthias Schumacher, Veronika Klimeck, Roland Gerhards
Climate change effects, such as rising temperature, carbon dioxide levels and extreme weather events, impact agriculture directly by reduction of crop yields and indirectly by increasing damage of crop pests. Therefore, preventive methods of plant protection, like cover cropping in integrated weed management, gain in importance. Their performance, however, depends on soil moisture and temperature in late summer. This study examined the effects of elevated temperature (+5 °C) and increasing drought levels (no, mild and severe drought) on four commercial and two self-composed cover crop mixtures and their weed suppression performance in a split-plot greenhouse experiment from 2020 to 2022. Cover crop (CC) and weed biomass were assessed, along with weed control efficacy (WCE) and soil coverage. A canonical correspondence analysis (CCA) was performed to identify drought and temperature tolerant species. Both, elevated temperature and increasing drought level, reduced CC biomass and soil cover by 50 %, severe drought even by more than 80 %. Weed biomass was affected similarly, only severe drought reduced it by more than 90 %. Nevertheless, CC mixtures, and the self-composed mixtures in particular, reduced weed biomass further and showed consistently WCE of more than 80 % and up to 98 %. The CCA revealed that Sorghum bicolor, Brassica carinata and Camelina sativa are promising species for future CC mixtures. Even though their biomass and soil coverage were reduced drastically by the examined climate change effects, CC mixtures still showed a high weed control ability. This resilience might be improved further by adjusted sowing dates and establishment methods and in turn improve CC performance under adverse climate change conditions.
{"title":"Climate change effects on the weed suppressive ability of several cover crop mixtures","authors":"Matthias Schumacher, Veronika Klimeck, Roland Gerhards","doi":"10.1016/j.cropro.2025.107514","DOIUrl":"10.1016/j.cropro.2025.107514","url":null,"abstract":"<div><div>Climate change effects, such as rising temperature, carbon dioxide levels and extreme weather events, impact agriculture directly by reduction of crop yields and indirectly by increasing damage of crop pests. Therefore, preventive methods of plant protection, like cover cropping in integrated weed management, gain in importance. Their performance, however, depends on soil moisture and temperature in late summer. This study examined the effects of elevated temperature (+5 °C) and increasing drought levels (no, mild and severe drought) on four commercial and two self-composed cover crop mixtures and their weed suppression performance in a split-plot greenhouse experiment from 2020 to 2022. Cover crop (CC) and weed biomass were assessed, along with weed control efficacy (WCE) and soil coverage. A canonical correspondence analysis (CCA) was performed to identify drought and temperature tolerant species. Both, elevated temperature and increasing drought level, reduced CC biomass and soil cover by 50 %, severe drought even by more than 80 %. Weed biomass was affected similarly, only severe drought reduced it by more than 90 %. Nevertheless, CC mixtures, and the self-composed mixtures in particular, reduced weed biomass further and showed consistently WCE of more than 80 % and up to 98 %. The CCA revealed that <em>Sorghum bicolor</em>, <em>Brassica carinata</em> and <em>Camelina sativa</em> are promising species for future CC mixtures. Even though their biomass and soil coverage were reduced drastically by the examined climate change effects, CC mixtures still showed a high weed control ability. This resilience might be improved further by adjusted sowing dates and establishment methods and in turn improve CC performance under adverse climate change conditions.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107514"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145657151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-02DOI: 10.1016/j.cropro.2026.107535
Fernando Semmelroth de Assunção e Amaral , Giovana Moraes de Souza , Rafael Brandão Garcia , Marcelo Pedreira de Miranda , Celso Omoto
In Brazil, control of the Asian citrus psyllid, Diaphorina citri, primarily relies on insecticides. Recently, field failures in controlling D. citri with some insecticides have been reported. This study investigates the susceptibility of five field populations of D. citri from key citrus-producing areas in the State of São Paulo, Brazil, to the three most used insecticides (bifenthrin, imidacloprid, and malathion). Subsequently, to characterize resistance under laboratory conditions, resistant strains were selected from one of the least susceptible field populations of D. citri located in Tabatinga, São Paulo. To provide evidence of field-evolved resistance, the effectiveness of imidacloprid was tested through foliar spray and soil drench applications. Leaf-dip bioassays characterized susceptibility of D. citri to bifenthrin, imidacloprid, and malathion. Resistance ratios among field populations of D. citri ranged from 39.6- to 192.7-fold for bifenthrin, 22.2- to 271.2-fold for imidacloprid, and 6.6- to 37.1-fold for malathion, compared to a susceptible reference strain. Following six generations of laboratory selection pressure in a field population of D. citri, resistance ratios increased to 1037.3-fold for bifenthrin, 790.6-fold for imidacloprid, and 298.9-fold for malathion. Low efficacy of imidacloprid against field populations of D. citri was observed in both application methods. This is the first report of field-evolved resistance of D. citri to bifenthrin, imidacloprid, and malathion insecticides in the citrus belt of São Paulo State, Brazil. Therefore, the evolution of resistance might be one of the reasons for the increased population density of D. citri. This research will help implement Insecticide Resistance Management (IRM) strategies for D. citri in Brazilian citrus groves.
{"title":"Field-evolved resistance of Diaphorina citri (Hemiptera: Psyllidae) to insecticides in Brazil","authors":"Fernando Semmelroth de Assunção e Amaral , Giovana Moraes de Souza , Rafael Brandão Garcia , Marcelo Pedreira de Miranda , Celso Omoto","doi":"10.1016/j.cropro.2026.107535","DOIUrl":"10.1016/j.cropro.2026.107535","url":null,"abstract":"<div><div>In Brazil, control of the Asian citrus psyllid, <em>Diaphorina citri</em>, primarily relies on insecticides. Recently, field failures in controlling <em>D. citri</em> with some insecticides have been reported. This study investigates the susceptibility of five field populations of <em>D. citri</em> from key citrus-producing areas in the State of São Paulo, Brazil, to the three most used insecticides (bifenthrin, imidacloprid, and malathion). Subsequently, to characterize resistance under laboratory conditions, resistant strains were selected from one of the least susceptible field populations of <em>D. citri</em> located in Tabatinga, São Paulo. To provide evidence of field-evolved resistance, the effectiveness of imidacloprid was tested through foliar spray and soil drench applications. Leaf-dip bioassays characterized susceptibility of <em>D. citri</em> to bifenthrin, imidacloprid, and malathion. Resistance ratios among field populations of <em>D. citri</em> ranged from 39.6- to 192.7-fold for bifenthrin, 22.2- to 271.2-fold for imidacloprid, and 6.6- to 37.1-fold for malathion, compared to a susceptible reference strain. Following six generations of laboratory selection pressure in a field population of <em>D. citri</em>, resistance ratios increased to 1037.3-fold for bifenthrin, 790.6-fold for imidacloprid, and 298.9-fold for malathion. Low efficacy of imidacloprid against field populations of <em>D. citri</em> was observed in both application methods. This is the first report of field-evolved resistance of <em>D. citri</em> to bifenthrin, imidacloprid, and malathion insecticides in the citrus belt of São Paulo State, Brazil. Therefore, the evolution of resistance might be one of the reasons for the increased population density of <em>D. citri</em>. This research will help implement Insecticide Resistance Management (IRM) strategies for <em>D. citri</em> in Brazilian citrus groves.</div></div>","PeriodicalId":10785,"journal":{"name":"Crop Protection","volume":"202 ","pages":"Article 107535"},"PeriodicalIF":2.5,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145893701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号