Plant disease最新文献_第5页

Pathogenic characteristics of Berkeleyomyces basicola Causing Black Root Rot of Carrot. 胡萝卜黑根腐病的基曲菌致病特性研究。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-10 DOI: 10.1094/PDIS-07-25-1516-SC

Miljan Grkinić, Mira Vojvodić, Dušan Nikolić, Aleksandra Bulajić

{"title":"Pathogenic characteristics of Berkeleyomyces basicola Causing Black Root Rot of Carrot.","authors":"Miljan Grkinić, Mira Vojvodić, Dušan Nikolić, Aleksandra Bulajić","doi":"10.1094/PDIS-07-25-1516-SC","DOIUrl":"https://doi.org/10.1094/PDIS-07-25-1516-SC","url":null,"abstract":"The pathogenic soilborne and postharvest fungus Berkeleyomyces basicola, as newly reported pathogen in Serbia, caused significant disease symptoms on carrot roots and seedlings in inoculation assays. In October 2023, machine-washed and cold-stored carrot roots showed symptoms of black rot of patches and abundant sporulation. The influence of the postharvest treatment of machine washing was confirmed by additional sampling at the production site. The collected roots were machine or manually washed, and stored under similar conditions as during shelf life (cold storage followed by incubation at room temperature). The machine-washed roots had a much higher disease incidence than the manually washed roots (75% and 15%, respectively). From all samples, only uniform Berkeleyomyces-like, dark grey colonies were obtained. Morphology and multilocus phylogeny (based on ITS, LSU and MCM7) confirmed the presence of Berkeleyomyces basicola. Koch's postulates were confirmed after artificial inoculations of carrot roots using spraying or injecting spore suspension or inserting colony fragments, and symptoms developed on both wounded and non-wounded roots seven days after inoculation. Pathogenicity tests on wounded and non-wounded carrot seedlings by spraying or watering with spore suspension or placing colony fragments next to root neck, showed that B. basicola can infect and sporulate only wounded carrot seedlings. The ability of B. basicola to infect carrot seedlings had not been tested previously, and our results suggest that carrot could be infected earlier than postharvest, as previously believed. In 2024, a follow-up survey of fresh market, symptomatic carrot roots confirmed continuous presence of B. basicola in Serbia.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145034001","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}

引用次数: 0

Absence of Fitness Trade-Offs in Fungicide-Resistant Venturia inaequalis: Evidence Along an Altitudinal Gradient. 在抗杀菌剂的不均等文氏菌中缺乏适合度权衡：沿海拔梯度的证据。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-09 DOI: 10.1094/PDIS-07-25-1586-RE

Giuliana Maddalena, Beatrice Lecchi, Mattia Peracchi, Giacomo Pigni, Giuseppe Russo, Silvia Laura Toffolatti

{"title":"Absence of Fitness Trade-Offs in Fungicide-Resistant Venturia inaequalis: Evidence Along an Altitudinal Gradient.","authors":"Giuliana Maddalena, Beatrice Lecchi, Mattia Peracchi, Giacomo Pigni, Giuseppe Russo, Silvia Laura Toffolatti","doi":"10.1094/PDIS-07-25-1586-RE","DOIUrl":"https://doi.org/10.1094/PDIS-07-25-1586-RE","url":null,"abstract":"Venturia inaequalis, a hemibiotrophic ascomycete, is the causal agent of apple scab, a major disease affecting apple production worldwide. The widespread use of fungicides in orchard management has led to the selection of resistant strains. To limit the spread of these resistant strains, it is essential to understand their competitive fitness within the population. In this study, we evaluated the resistance profiles and fitness components of 23 V. inaequalis isolates from both treated and untreated orchards in Northern Italy, focusing on five fungicides: dodine, cyprodinil, trifloxystrobin, boscalid, and myclobutanil. Fitness parameters, including mycelial growth, conidia number, and conidia size, were assessed in relation to fungicide resistance and environmental factors, such as altitude. The results revealed that, overall, resistant and sensitive strains showed no significant differences in fitness, except for cyprodinil-resistant strains, which exhibited enhanced mycelial growth and increased conidia size, and dodine-resistant strains, which produced smaller conidia. Additionally, altitude influenced conidial size, with higher elevation sites correlating with smaller conidia. These findings suggest that both genetic and environmental factors contribute to conidial variation, which may impact pathogen dispersal and infection dynamics. This study highlights the resilience and potential for spread of fungicide-resistant strains and underscores the need for integrated resistance management strategies to maintain sustainable and high quality apple production.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030387","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}

引用次数: 0

Pantoea ananatis as the Emerging Causal Agent of Novel Bacterial Leaf Blight in Rice: Characterization and Management in Anhui, China. 作为水稻新型细菌性叶枯病的新病原：安徽的鉴定与管理。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-09 DOI: 10.1094/PDIS-04-25-0931-RE

Hao-Yu Zang, Huiyong Xu, Zhaoyang Zheng, Xue Yang, Rui Pan, Xiao-Xia Feng, Shan Shi, Qi-Sheng Zhang, Hui Wang, Qian-Qian Wan, Rende Qi, Chun-Yan Gu

{"title":"Pantoea ananatis as the Emerging Causal Agent of Novel Bacterial Leaf Blight in Rice: Characterization and Management in Anhui, China.","authors":"Hao-Yu Zang, Huiyong Xu, Zhaoyang Zheng, Xue Yang, Rui Pan, Xiao-Xia Feng, Shan Shi, Qi-Sheng Zhang, Hui Wang, Qian-Qian Wan, Rende Qi, Chun-Yan Gu","doi":"10.1094/PDIS-04-25-0931-RE","DOIUrl":"https://doi.org/10.1094/PDIS-04-25-0931-RE","url":null,"abstract":"Since its emergence in 2020, a novel bacterial leaf blight caused by Pantoea ananatis has posed a serious threat to rice production in Anhui Province, China. Through verification via Koch's postulates and three years of field monitoring, P. ananatis strain HQ01 was identified as the dominant pathogen, exhibiting high virulence even at low inoculum concentrations (10² CFU/mL). Genomic analysis further revealed virulence-associated traits, including type III, IV, and VI secretion systems (T3SS/T4SS/T6SS), iron acquisition genes, and 160 carbohydrate-active enzymes linked to plant cell wall degradation. Meanwhile, resistance screening of 21 rice cultivars showed widespread susceptibility, with 95% of varieties classified as susceptible. In parallel, in vitro and in vivo trials identified tetramycin and zinc thiazole as the most effective chemical candidates. Despite these findings, control strategies remain inadequate for managing severe outbreaks. This study thus highlights the urgent need to develop resistant cultivars and sustainable bactericides to combat this emerging disease.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030352","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}

引用次数: 0

Resistance in Capsicum Species and Cultivars to Colletotrichum scovillei and Implications for Fungicide Applications. 辣椒品种对炭疽病菌的抗性及其杀菌剂应用意义。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-09 DOI: 10.1094/PDIS-06-25-1172-RE

Anthony P Keinath, William Rutter

{"title":"Resistance in Capsicum Species and Cultivars to Colletotrichum scovillei and Implications for Fungicide Applications.","authors":"Anthony P Keinath, William Rutter","doi":"10.1094/PDIS-06-25-1172-RE","DOIUrl":"https://doi.org/10.1094/PDIS-06-25-1172-RE","url":null,"abstract":"Green fruit anthracnose caused by the fungus Colletotrichum scovillei is an emerging disease on various types of peppers (Capsicum spp.) in the eastern United States. Sixteen cultivars, representing 11 horticultural fruit types from four species of Capsicum, C. annuum, C. baccatum, C. chinese, and C. frutescens, were evaluated for potential fruit rot resistance to C. scovillei in replicated field plots in summer 2022 and 2023. Fruit was naturally inoculated by facilitating spread of conidia of C. scovillei with overhead irrigation from inoculated jalapeño fruit on plants located between plots into test plots. C. chinense cultivars Roulette and Carolina Reaper and C. frutescens cultivars Tabasco and Malagueta had significantly lower fruit disease incidence than the other 12 cultivars in both years. In a second experiment, conducted in fall 2022 and 2023, four C. annuum pepper types were treated or not treated with a preventative rotation of mancozeb and azoxystrobin at labeled rates. The fungicide treatment reduced fruit disease incidence fivefold compared to the nontreated control in both years. In the nontreated plots, the reduced susceptibility of jalapeño, New Mexico chili, and Italian frying peppers provided 50% fruit rot control relative to susceptible bell pepper. In fungicide-treated plots, however, mean percentage control was 80% for the non-bell cultivars. In 2022, marketable weight and number were fivefold greater on fungicide-treated plants than non-treated plants, but in 2023, yields were not affected by fungicides. C. frutescens may be useful as a source of resistance to develop new pepper cultivars that would help growers manage green fruit anthracnose.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030303","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}

引用次数: 0

Fluorescent mesoporous silica nanoparticles for targeted tebuconazole delivery against brown root rot in rubber trees. 荧光介孔二氧化硅纳米颗粒靶向递送苯康唑防治橡胶树褐根腐病。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-09 DOI: 10.1094/PDIS-05-25-1035-SC

Yan Zhang, Fang Tian, Congying Xu, Xiaoyu Liang, Shanying Zhang, Meng Wang, Yu Zhang

{"title":"Fluorescent mesoporous silica nanoparticles for targeted tebuconazole delivery against brown root rot in rubber trees.","authors":"Yan Zhang, Fang Tian, Congying Xu, Xiaoyu Liang, Shanying Zhang, Meng Wang, Yu Zhang","doi":"10.1094/PDIS-05-25-1035-SC","DOIUrl":"https://doi.org/10.1094/PDIS-05-25-1035-SC","url":null,"abstract":"Brown root rot, caused by Phellinus noxius, is a major threat to rubber tree cultivation, resulting in substantial economic losses. Traditional control methods, such as root irrigation with fungicides, are labor-intensive, water-consuming, and inefficient, particularly in regions with limited water resources. This study introduces fluorescent mesoporous silica nanoparticles (FL-MSNs) as a novel delivery platform for tebuconazole to target P. noxius infection. The nanoparticles, with a high fungicide loading efficiency (43.81%), exhibit controlled release under varying pH conditions, providing sustained tebuconazole delivery. Fluorescent labeling allowed tracking of the nanoparticles, confirming effective transport from leaves to roots via phloem. Greenhouse trials demonstrated that foliar application of Teb@FL-MSNs resulted in an 84% survival rate of infected seedlings, significantly outperforming untreated controls, which exhibited 100% mortality. The nanoparticle formulation also reduced lesion size, highlighting its potential to improve disease control while minimizing fungicide use. These findings emphasize the advantages of Teb@FL-MSNs over traditional methods, offering a more efficient, environmentally friendly, and sustainable approach to managing brown root rot in rubber plantations.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145030321","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}

引用次数: 0

Screening of Cannabis sativa germplasm for susceptibility to Septoria leaf spot. 大麻叶斑病易感种质筛选。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-08 DOI: 10.1094/PDIS-07-25-1367-RE

Jocelyn A Schwartz, Lucía Vignale, Tyler Gordon, Zachary Stansell, Lawrence B Smart, Christine D Smart

{"title":"Screening of Cannabis sativa germplasm for susceptibility to Septoria leaf spot.","authors":"Jocelyn A Schwartz, Lucía Vignale, Tyler Gordon, Zachary Stansell, Lawrence B Smart, Christine D Smart","doi":"10.1094/PDIS-07-25-1367-RE","DOIUrl":"https://doi.org/10.1094/PDIS-07-25-1367-RE","url":null,"abstract":"Septoria leaf spot, caused by the fungal pathogen Septoria cannabis, is a common disease of field-grown hemp (Cannabis sativa L.). The development of disease-resistant cultivars presents a promising strategy for managing this disease. To evaluate hemp germplasm for susceptibility to Septoria leaf spot, diverse hemp entries from the USDA-ARS Plant Genetic Resources Unit, commercially available cultivars, and Cornell breeding lines were evaluated in replicated field trials in Geneva, NY. In 2023, 81 entries were screened, and in 2024, 105 entries were screened for disease severity on a weekly basis. Relative area under disease progress curve (rAUDPC) values were calculated to quantify susceptibility across two years. Significant variations in rAUDPC were observed among entries, ranging from 0.01 to 13.60 in 2023 and from 0.10 to 21.20 in 2024. Final disease severity ranged from 0.01% to 31.30% in 2023 and from 0.00% to 36.00% in 2024. Nine entries that consistently displayed low disease severity and are likely resistant to S. cannabis were identified. Disease severity was not significantly correlated with plant sex. Several resistant entries were of Asian origin. This study establishes foundational knowledge for breeding programs targeting Septoria leaf spot resistance and emphasizes the value of diverse hemp germplasm in disease management.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145016102","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}

引用次数: 0

Identification of novel sources and genetic mapping for Bacterial Leaf Streak resistance in a geographically diverse panel of wheat. 小麦不同地理区系细菌性叶片条纹抗性新来源鉴定及遗传定位。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-08 DOI: 10.1094/PDIS-05-25-1021-RE

Subash Thapa, Mandeep Singh, Harsimardeep Gill, Shaukat Ali, Jyotirmoy Halder, Dante Koupal, Jagdeep Singh Sidhu, Sunish Sehgal

{"title":"Identification of novel sources and genetic mapping for Bacterial Leaf Streak resistance in a geographically diverse panel of wheat.","authors":"Subash Thapa, Mandeep Singh, Harsimardeep Gill, Shaukat Ali, Jyotirmoy Halder, Dante Koupal, Jagdeep Singh Sidhu, Sunish Sehgal","doi":"10.1094/PDIS-05-25-1021-RE","DOIUrl":"https://doi.org/10.1094/PDIS-05-25-1021-RE","url":null,"abstract":"Bacterial leaf streak (BLS), caused by Xanthomonas translucens pv. undulosa (Xtu), has recently emerged as a significant threat to wheat production in the Northern Great Plains region of the US. Deploying resistant cultivars is an economical and practical method of controlling BLS. To identify novel sources of BLS resistance, we screened a set of 355 bread wheat landraces and cultivars representing global diversity for their response to BLS. A wide distribution of seedling responses against BLS was observed, with most genotypes displaying a moderately to highly susceptible response. Notably, we identified 5 resistant and 33 moderately resistant responses. A high-resolution genome-wide association study (GWAS) using 302,524 high-quality single-nucleotide polymorphisms (SNPs) identified ten significant marker-trait associations (MTAs) on chromosomes 1A, 1D, 3B, 4A, and 5A, corresponding to unique genomic regions associated with BLS resistance. Compared to previous studies, four of these genomic regions are likely novel. Of these, MTA 'scaffold15531_2782724' associated with q5A.1 was highly significant (-log10P = 9.39) and exhibited the highest SNP effect (0.35). An association on chromosome 3B validated a previously identified 3B QTL mapped at ~6 Mbp in the hard red spring wheat cultivar 'Boost', and the high-resolution mapping from our study further refined the interval for this QTL. Furthermore, the narrow haplotype blocks reported in this study could be valuable for fine mapping of important regions. The novel resistant sources along with identified genomic loci and corresponding SNP markers from this study, would be helpful for wheat breeding programs to enhance BLS resistance.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145016026","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}

引用次数: 0

Tissue-specific endophytic microbiome responses to "Candidatus Liberibacter asiaticus" in two citrus cultivars. 两个柑桔品种对“亚洲自由候选菌”的组织特异性内生微生物组反应。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-05 DOI: 10.1094/PDIS-07-25-1430-RE

Mingxin Zheng, Yanhua Zhang, Xiaoqing Lin, Haolin Wang, Meirong Xu, Xiaoling Deng, Zheng Zheng

{"title":"Tissue-specific endophytic microbiome responses to \"Candidatus Liberibacter asiaticus\" in two citrus cultivars.","authors":"Mingxin Zheng, Yanhua Zhang, Xiaoqing Lin, Haolin Wang, Meirong Xu, Xiaoling Deng, Zheng Zheng","doi":"10.1094/PDIS-07-25-1430-RE","DOIUrl":"https://doi.org/10.1094/PDIS-07-25-1430-RE","url":null,"abstract":"Citrus Huanglongbing (HLB), caused by \"Candidatus Liberibacter asiaticus\" (CLas), is a destructive disease threatening global citrus industry. Although citrus cultivars differ in HLB sensitivity, how infection alters endophytic bacterial communities in cultivars with contrasting susceptibility remains unclear. Here, we compared endophytic microbiome shifts in leaf and root tissue of HLB-susceptible Shatangju mandarin (C. reticulata cv. Shatangju) and HLB-tolerant Shatian pomelo (C. maxima cv. Shatian) at 10 months post grafting (MPG) with CLas-infected buds. Infected Shatangju mandarin showed severe symptoms and higher CLas levels in leaf than root, while infected Shatian pomelo remained asymptomatic with higher CLas in root than leaf. High-throughput 16S rRNA gene sequencing revealed that CLas infection restructured endophytic microbial community in tissue-specific manner. CLas-infected Shatian pomelo leaf displayed increased microbial diversity and network complexity, while CLas-infected Shatangju mandarin root harbored more disease-suppressive taxa like Streptomyces. Across both cultivars, network complexity correlated inversely with CLas abundance. Key genera (e.g., Pseudomonas, Streptomyces, Prevotella) correlated positively with CLas, suggesting roles in mitigating pathogen effects. Predicted functional profiling indicated activated pathways (amino acid metabolism, terpenoid/polyketide biosynthesis, xenobiotic biodegradation) potentially supporting host defense in infected tissues. The HLB tolerance of Shatian pomelo appeared linked to tissue-specific bacterial restructuring, particularly recruitment of antibiotic-producing bacteria and enhanced metabolic resilience. These findings elucidated cultivar-specific microbial strategies against CLas, offering insights for microbiome-mediated HLB management.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145001205","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}

引用次数: 0

Mefenoxam sensitive isolates of Phytophthora infestans can quickly acquire and lose resistance to this fungicide. 对该杀菌剂敏感的疫霉分离株可以迅速获得和失去对该杀菌剂的抗性。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-05 DOI: 10.1094/PDIS-05-25-1110-RE

Melissa Regnier, Juliana González-Tobón, Martha E Cárdenas, Hilary Mayton, Giovanna Danies, Silvia Restrepo

{"title":"Mefenoxam sensitive isolates of Phytophthora infestans can quickly acquire and lose resistance to this fungicide.","authors":"Melissa Regnier, Juliana González-Tobón, Martha E Cárdenas, Hilary Mayton, Giovanna Danies, Silvia Restrepo","doi":"10.1094/PDIS-05-25-1110-RE","DOIUrl":"https://doi.org/10.1094/PDIS-05-25-1110-RE","url":null,"abstract":"Phytophthora infestans is an oomycete that causes late blight disease in multiple solanaceous crops, including potato and tomato. This makes it a worldwide concern for farmers, given the level of crop loss and its explosive epidemic potential. Although fungicides have traditionally been used for managing this disease, populations of P. infestans resistant to fungicides have been documented. Furthermore, it has been shown that isolates considered originally sensitive to mefenoxam acquire resistance to it after a single exposure in vitro to low concentrations of this widely used fungicide. Previous studies have measured such resistance in terms of mycelial growth. However, there is still much unknown regarding how this phenomenon is triggered. Here, we explored the dynamics of how this resistance is gained and lost, both in terms of mycelial growth and sporangial production. Isolates that acquired resistance to mefenoxam: i) did not sporulate significantly more than they did before, ii) were not affected by repeated exposures to a high concentration of mefenoxam, iii) lost the acquired resistance after a single passage through medium without mefenoxam, and iv) re-acquired the resistance after a single re-exposure to a low concentration of mefenoxam. Such dynamic behavior aligns well with the pleiotropic drug resistance mechanism that has been proposed as the molecular process behind the acquired resistance phenomenon, as well as with an epigenetic mode of regulation. This study narrows our knowledge gap on this phenomenon and reinforces the importance of deciphering whether it could be an issue under field conditions.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145001198","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}

引用次数: 0

Host quality and composition of multi-host environment impact the maintenance of members of the wheat dwarf disease pathosystem in non-crop areas. 在非农区，寄主质量和多寄主环境的组成影响小麦矮秆病病原系统成员的维持。

IF 4.4 2区农林科学

Plant disease Pub Date : 2025-09-05 DOI: 10.1094/PDIS-10-24-2062-RE

Thomas Armand, Marlène Souquet, Matthias Rapp, Emmanuel Jacquot

{"title":"Host quality and composition of multi-host environment impact the maintenance of members of the wheat dwarf disease pathosystem in non-crop areas.","authors":"Thomas Armand, Marlène Souquet, Matthias Rapp, Emmanuel Jacquot","doi":"10.1094/PDIS-10-24-2062-RE","DOIUrl":"https://doi.org/10.1094/PDIS-10-24-2062-RE","url":null,"abstract":"Harvest represents a challenge for the persistence of insect-transmitted viruses in agroecosystems. To overcome this challenge, some viruses infect non-crop plants as reservoirs for future introduction to newly sown fields. The wheat dwarf disease (WDD), one of the most important viral diseases on cereals, is caused by the wheat dwarf virus (WDV) and is transmitted by the leafhopper Psammotettix alienus. To better understand the contribution of non-crop species in the epidemiology of WDD, plant-virus (i.e. infection rate of WDV-b1 and WDV-w1 isolates) and plant-vector (i.e. survival and fecundity) interactions were monitored on 20 non-crop Poaceae (NCP) species. Results showed that i) the host range of WDV is wider than expected and ii) NCP can be clustered according to their host quality for WDV and/or P. alienus. This suggests that NCP species contribute differentially to the maintenance of members of the WDD pathosystem. In addition, Bromus hordeaceus and Phalaris arundinaceae (two species with contrasted host quality for WDV and P. alienus) were included in multi-host arena experiments to assess the impact of a heterogeneous plant environment on leafhopper preferences and WDV-w1 infection. Collected data showed that P. alienus prefers B. hordeaceus (a poor efficient host for WDV) for oviposition. This could lead to a dilution of viruliferous vectors in environments containing B. hordeaceus plants as hosts for WDV-w1. While the isolate-specificity of dilution effect cannot be excluded, this study indicate that host quality and composition of plant populations are important for maintenance of WDV and P. alienus in non-crop areas.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145001207","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}

引用次数: 0