Phytopathology最新文献

{"title":"Mechanism of the Non-Host Flavonoid Nobiletin in Inhibiting the Phytopathogen <i>Sclerotinia sclerotiorum</i>.","authors":"Ziling Liu, Yulong Wang, Xintong Cao, Yuan Gao, Pingzhou Du, Hongyu Pan, Jingyuan Chen","doi":"10.1094/PHYTO-12-25-0387-R","DOIUrl":"10.1094/PHYTO-12-25-0387-R","url":null,"abstract":"<p><p><i>Sclerotinia sclerotiorum</i> is a devastating phytopathogenic fungus with a broad host range, which is partly attributed to its ability to detoxify a wide array of host-derived secondary metabolites. Among these, flavonoids are one of the most widespread classes of plant secondary metabolites and are ubiquitously present in both host and non-host plants of <i>S. sclerotiorum</i>. Understanding the mechanisms by which non-host flavonoids inhibit this pathogen is therefore crucial, not only for elucidating the biochemical basis of non-host resistance but also for discovering novel plant-derived fungicides. In this study, we compared the differential inhibitory effects of various flavonoid types-including isoflavones, flavonols, flavanones, and citrus-derived polymethoxyflavones (PMFs)-on <i>S. sclerotiorum</i>. Our results revealed differential sensitivities of the fungus to these compounds, corresponding with its varying metabolic capabilities. Furthermore, transcriptomic analysis demonstrated that the non-host flavonoid nobiletin and the host-derived, degradable flavonol quercetin elicit fundamentally different gene expression responses in the fungus. Further physiological and biochemical analyses showed that nobiletin induced reactive oxygen species (ROS) accumulation in <i>S. sclerotiorum</i> at later stages of treatment but had no significant effects on plasma membrane integrity or carbohydrate metabolism. The partial rescue of growth inhibition by ascorbic acid suggests that ROS accumulation contributes to the antifungal activity of nobiletin. These findings provide new insights into the antifungal mechanisms of PMFs and support their potential application in fungicide development.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"PHYTO12250387R"},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148593225","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}

{"title":"Distinct Lineages of <i>Pantoea ananatis</i> Associated with Rice Differ in Toxin Biosynthesis Gene Content and Host Specialization.","authors":"Mitchell Giebler, Emily Luna, Camila Nicolli, Federico Martin, Rodrigo Pedrozo, Prasanna Joglekar, Alejandra I Huerta, Yulin Jia, Jan E Leach","doi":"10.1094/PHYTO-04-26-0138-R","DOIUrl":"10.1094/PHYTO-04-26-0138-R","url":null,"abstract":"<p><p><i>Pantoea ananatis</i> has recently emerged as a causal agent of Pantoea leaf blight and Pantoea panicle blight of rice in the United States, raising concerns about its potential impact on rice production. Despite increasing reports of the disease, the mechanisms underlying host specialization and virulence within this pathosystem remain poorly understood. Here, we combined comparative genomics and in-planta assays to investigate population structure and virulence determinants among rice-associated <i>P. ananatis</i> strains. Average nucleotide identity analysis of <i>P. ananatis</i> genomes resolved two lineages with contrasting host associations. One lineage, composed of strains recovered almost exclusively from rice, lacked the HiVir operon responsible for synthesis of the phosphonate toxin pantaphos. A second, broadly distributed lineage included <i>P. ananatis</i> isolated from diverse hosts, including rice, and many contained the HiVir operon. HiVir-mediated pantaphos production induced necrotic symptom development but was not required for bacterial replication within rice tissue. Accordingly, strains lacking HiVir, including those from the rice-associated lineage and targeted mutants, exhibited reduced necrosis while achieving bacterial population sizes comparable to those of wild-type generalist strains during infection of rice. Conversely, host-range experiments showed that rice-associated strains colonized onion tissue less than generalist strains, consistent with evolutionary specialization for rice. Comparative pangenome analysis supported the separation of lineages and identified hundreds of lineage-specific genes that may underpin host associations. These findings demonstrate that <i>P. ananatis</i> populations associated with rice comprise distinct evolutionary lineages with differing genomic features and virulence strategies and reveal a decoupling between symptom development and bacterial proliferation during infection of rice.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"PHYTO04260138R"},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148272738","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}

{"title":"Machine Learning and Statistical Models for Genomic Selection of Phytophthora Fruit Rot Resistance in Watermelon.","authors":"Rahul Kumar, Jennifer Ikerd, Raman Dhariwal, Raghupathy Karthikeyan, Chandrasekar Kousik","doi":"10.1094/PHYTO-03-26-0072-R","DOIUrl":"https://doi.org/10.1094/PHYTO-03-26-0072-R","url":null,"abstract":"<p><p>Breeding for Phytophthora fruit rot (PFR) resistance caused by the devastating pathogen <i>Phytophthora capsici</i> remains challenging in watermelon mainly due to phenotyping constraints. To overcome these bottlenecks, we developed and validated genomic selection models using an interspecific recombinant inbred line (RIL, F₁₁) population derived from USVL531-MDR (resistant, <i>Citrullus mucosospermus</i>) × USVL677-PMS (susceptible, <i>Citrullus lanatus</i>) and a segregating F₂ population (USVL531-MDR × 'Calhoun Grey'). Mature fruits from both populations were artificially inoculated under controlled conditions and phenotyped for lesion diameter, visible pathogen growth diameter, and sporulation intensity. Fourteen genomic selection models comprising ten parametric approaches (Bayesian and regression-based), one semi-parametric model (RKHS), and three machine learning algorithms (Random Forest, SVM, XGBoost) were evaluated for their performance. Parametric models achieved high predictive accuracy in the RIL population (r = 0.700-0.718 in 10-fold cross-validation; r = 0.694-0.713 in 5-fold cross-validation), while the F₂ population showed moderate accuracies, with GBLUP performing well under 10-fold cross-validation (r = 0.476) and Bayesian ridge regression under 5-fold cross-validation (r = 0.433). Coincidence analysis demonstrated that genomic prediction effectively captured top-performing RILs, with 10% and 20% selection intensities showing strong overlap with phenotypic selection and Bayesian models achieving up to 85% coincidence. These results establish a solid framework for application of genomic selection in watermelon PFR resistance breeding programs.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149113916","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}

{"title":"Temporal Dynamics of Viral Load and Genomic Diversity of Plantago Asiatica Mosaic Virus During Long-Term Infection in a Herbaceous Perennial.","authors":"Yuna Yamamoto, Azusa Okawa, Kagari Sakugawa, Nami Minato, Tsutomu Arie, Ken Komatsu","doi":"10.1094/PHYTO-11-25-0357-R","DOIUrl":"https://doi.org/10.1094/PHYTO-11-25-0357-R","url":null,"abstract":"<p><p>Plant positive-strand RNA viruses exhibit high mutation rates that drive genetic diversity and adaptation to different hosts. While herbaceous perennials potentially serve as reservoirs for viral diversification through persistent infections, the mechanisms underlying this process remain largely unexplored. We investigated the temporal dynamics of viral load and genomic diversity of Plantago asiatica mosaic virus (PlAMV) during long-term infection in its natural herbaceous perennial host, <i>Plantago asiatica</i>. Mechanical inoculation of <i>P. asiatica</i> with PlAMV isolate Vi resulted in systemic infection that persisted through aboveground senescence (withering) and regeneration cycles. RT-qPCR analysis revealed that PlAMV migrated from inoculated leaves to uninoculated upper leaves and roots, maintaining infection during overwintering by accumulating in roots. Population diversity analysis of the triple gene block protein (TGBp) 1-3 region showed significantly increased mutation frequencies after the aboveground senescence and regeneration (172 days post-inoculation) compared to those observed before senescence (21 and 45 days post-inoculation) in three of four infected plants. Chimeric viruses constructed with mutations acquired during persistent infection exhibited altered pathogenicity and accumulation patterns in <i>P. asiatica</i>, <i>Nicotiana benthamiana</i>, and <i>Chenopodium quinoa</i>. Host range analysis of natural PlAMV isolates representing the major phylogenetic clades revealed clade-dependent and even isolate-specific differences in infectivity across 17 plant species. These findings provide the first experimental evidence that this perennial species acts as an amplifier of viral genetic diversity, contributing to a deeper understanding of how persistent infection in such a host can shape virus evolution and potentially facilitating the emergence of variants with expanded host ranges.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149114085","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}

{"title":"Plant Pathology and the Qualitative Social Sciences: Toward an Interdisciplinary Dialogue.","authors":"Camilo Castillo","doi":"10.1094/PHYTO-02-26-0049-RVW","DOIUrl":"https://doi.org/10.1094/PHYTO-02-26-0049-RVW","url":null,"abstract":"<p><p>This article attends to recent calls from plant pathology to advance toward interdisciplinary approaches. It argues for the importance of qualitative social science as a catalyst for new research and strategies to foreground the societal relevance of plant diseases. Through a narrative review and thematic analysis, the article first identifies how the social dimensions of plant disease have been incorporated within plant pathology in studies addressing the economic impacts of plant disease, its socio-historical importance and technology adoption. Second, it examines the qualitative social science literature identified in the review, organizing its contributions to the study of plant diseases into four categories.: i) institutions, ii) actors, iii) social processes, iv) relational approaches. Based on these findings, the article discusses the need for interdisciplinary dialogue to situate plant disease more prominently in current societal debates on the transformation of food systems. However, as the article argues, achieving this will require a renewed understanding of interdisciplinarity in plant pathology - one that sees it as a negotiated process of building shared concerns around plant diseases. In this process, learning from and accepting differences between disciplines become essential for creating open and robust interfaces through which scientists from diverse fields can work together to study and address plant disease.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149114074","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}

{"title":"Fungicide Resistance Mutations to Oxathiapiprolin Display Clade-Specific Occurrence in <i>Pseudoperonospora cubensis</i>, Causal agent of Cucurbit Downy Mildew.","authors":"M Prieto-Torres, K N D'Arcangelo, K L Childs, K Avila, L M Quesada-Ocampo","doi":"10.1094/PHYTO-02-26-0046-R","DOIUrl":"https://doi.org/10.1094/PHYTO-02-26-0046-R","url":null,"abstract":"<p><p><i>Pseudoperonospora cubensis</i>, the causal agent of cucurbit downy mildew, causes severe annual losses in cucurbit production. Management relies on frequent fungicide applications, with oxathiapiprolin (OXTP; FRAC 49) being a cornerstone of current programs. Because OXTP is classified as high risk for resistance development, monitoring for resistance alleles is critical. Although OXTP resistance mutations have been reported in other oomycetes, none had previously been documented in <i>P. cubensis</i>. In this study, we reconstructed the <i>P. cubensis</i> oxysterol-binding protein (OSBP) gene, the target of OXTP, and identified the N772I resistance mutation by Sanger sequencing. We then developed a novel qPCR assay for high-throughput detection of resistance alleles. Screening more than 500 isolates revealed that the N772I resistance mutation is strongly associated with clade 2 isolates, which typically infect cucumber and cantaloupe and are also resistant to QoI and CAA fungicides. In contrast, clade 1 isolates primarily infecting squash, pumpkin, and watermelon remained largely sensitive. These findings provide the first evidence of OXTP resistance mutations in <i>P. cubensis</i>, demonstrate clade-specific occurrence of resistance mutations, and provide a diagnostic tool for rapid screening. Integration of this assay into biosurveillance systems will enable in-season monitoring and support more effective fungicide programs for cucurbit downy mildew.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149113925","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}

{"title":"Comparative Analyses of the Order Enterobacterales Support the Importance of Methyl-Accepting Chemotaxis Proteins and ATP-Binding Cassette Transporters in the Pathogenicity of Soft Rot Pectobacteriaceae.","authors":"Yuan Zeng, Hanoch Senderowitz, Iris Yedidia, Amy O Charkowski","doi":"10.1094/PHYTO-06-26-0187-R","DOIUrl":"https://doi.org/10.1094/PHYTO-06-26-0187-R","url":null,"abstract":"<p><p>Methyl-accepting chemotaxis proteins (MCPs) are bacterial chemoreceptors that sense environmental and intracellular signals and regulate flagellar rotation through interactions with Che proteins. Some MCPs interact with ATP-binding cassette (ABC) transporters, which import and export various compounds across cell membranes. Using annotated prokaryotic genome assemblies, we assessed the abundance and organization of MCPs and ABC transporters in plant pathogenic Pectobacteriaceae and compared these features with those in other members of the Enterobacterales order, including <i>Escherichia</i>, <i>Yersinia</i>, <i>Pectobacterium</i>, <i>Salmonella</i>, <i>Erwinia</i>, and <i>Sodalis</i>. Soft rot Pectobacteriaceae encode at least 20 MCP genes per strain and contain diverse ligand-binding domains, including TarH, 4HB, HBM, NIT, dCache-1, sCache_2, Cache_3-Cache_2, FIST, Chase3, CZB, NIT, and Pas domains. Their genomes are also enriched in ABC transporters that transport sugars, peptides, amino acids, iron-siderophores, and the family 5, 6 and 9 transporters compared to other Enterobacterales. Some MCPs are clustered in Pectobacteriaceae, and some are collocated with ABC transporters. A subset of substrate-binding proteins of ABC transporters that bind to sugar, amino acid, mineral salt, iron, and polyamine may interact with MCPs in <i>Pectobacterium</i> to co-sense signals. Our findings suggest that soft rot Pectobacteriaceae are enriched in both MCPs and ABC transporters relative to many other members of Enterobacterales, supporting the potential importance of these proteins in adaptation to diverse environments and pathogenesis within the context of shared phylogenetic history. MCPs and ABC transporters therefore provide candidates for future functional studies of soft rot pathogenesis and may help identify strategies for plant disease management.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149114013","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}

{"title":"Quorum-Sensing Signal Molecule C10-HSL Exhibits a Cross-Kingdom Inhibition Effect on <i>Phytophthora sojae</i>.","authors":"Ke Dai, Xinyi Wu, Qingwen Su, Haixu Liu, Ying Xu, Zhuoqun Zhang","doi":"10.1094/PHYTO-01-26-0008-R","DOIUrl":"10.1094/PHYTO-01-26-0008-R","url":null,"abstract":"<p><p>N-acylhomoserine lactone (AHL) quorum-sensing signal molecules of bacteria are involved in regulating the inhibition effect of biocontrol agents on several plant diseases. However, the direct inhibition effect of AHL on pathogens and the molecular mechanism of inhibition remain unclear. Phytophthora root rot (PRR) of soybean, caused by <i>Phytophthora sojae</i>, is a devastating oomycete disease in soybean production. To investigate the application potential of AHL in PRR control, zoospore chemotaxis, oospore formation, mycelial growth, and pathogenicity in <i>P. sojae</i> responding to AHL were determined. The transcriptome of <i>P. sojae</i> in response to AHL was also analyzed. The key differentially expressed genes were quantitatively verified by qRT-PCR. We found that N-decanoyl-L-homoserine lactone (C10-HSL) was the most abundant AHL in the fermentation broth biocontrol strain <i>Pseudomonas mandelii</i>. C10-HSL repels <i>P. sojae</i> zoospores, inhibits <i>P. sojae</i> mycelial growth and oospore formation, and alleviates the pathogenicity of <i>P. sojae</i>. The inhibition effect was regulated mainly by nitrogen metabolism, efferocytosis, glycolysis/gluconeogenesis, and carbon metabolism pathways. <i>P. sojae</i> cell structures could disrupt and carbohydrate utilization could interfere with the response process. This result reveals that C10-HSL acts as a cross-kingdom signaling molecule to inhibit <i>P. sojae</i> and control PRR.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"PHYTO01260008R"},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148631578","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}

{"title":"Recurrent Invasion of Oregon's Coastal Forests by the Sudden Oak Death Pathogen: The NA2 Lineage's First Escape into the Wild.","authors":"Steph M Chase, Kelsey L Søndreli, Niklaus J Grünwald, Jared M LeBoldus","doi":"10.1094/PHYTO-04-26-0106-R","DOIUrl":"10.1094/PHYTO-04-26-0106-R","url":null,"abstract":"<p><p><i>Phytophthora ramorum</i>, the sudden oak death (SOD) pathogen, has invaded U.S. nurseries and western forests repeatedly. Invasions by three distinct clonal lineages (NA1, NA2, and EU1) have affected U.S. wildland forests since 2001. Most recently, NA2 established an invasive population in coastal forests surrounding Port Orford in southwest Oregon. This is the first instance of NA2 encountered outside of a nursery. We assessed this new invasion's diversity and population structure using single-nucleotide polymorphisms from whole-genome sequences of 195 isolates. Genomes were sampled from the nursery trade and from the forest invasion surrounding Port Orford. The NA2 forest invasion lacks genetic diversity and likely originated from a single introduction. A subset of NA2 isolates (10.8%) were genetically distant from all other isolates including each other. This distance was correlated with frequency of genomic runs of homozygosity. No evidence of hybridization was found, though NA2 and EU1 mating types are compatible and their ranges in wild forests overlap. The aggressiveness and sporulation of NA2 isolates were measured on three host tree species and compared with isolates of other lineages. NA2 and EU1 phenotypes were similar. NA2 caused larger lesions on Douglas-fir and tanoak seedlings than NA1, the lineage of the original introduction into Oregon forests. Results indicate that the NA2 population is not distinct from the older EU1 Oregon population in terms of population diversity, disease aggressiveness, or potential for spread. However, the introduction of NA2 has increased the SOD epidemic's range, risk of hybridization, overall genetic diversity, and adaptive potential.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"PHYTO04260106R"},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148580000","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}

{"title":"Dual Transcriptomic Analysis of Isolates of <i>Phytophthora sansomeana</i> with Varying Levels of Aggressiveness Compared with <i>P. sojae</i> During a Time Course Infection Assay of Soybean.","authors":"L M Hebb, J W Poelstra, A E Dorrance","doi":"10.1094/PHYTO-12-25-0395-R","DOIUrl":"10.1094/PHYTO-12-25-0395-R","url":null,"abstract":"<p><p><i>Phytophthora sansomeana</i> was detected in several soybean root rot surveys in the United States, alongside another well-studied oomycete, <i>P. sojae</i>. We compared the transcriptomic responses among three <i>P. sansomeana</i> isolates that differed in aggressiveness and <i>P. sojae</i> isolate OH25 with the most aggressive <i>P. sansomeana</i> isolate in a moderately susceptible soybean using dual host-pathogen RNA-Seq. At each time point, the relative pathogen read abundance was higher following inoculation with <i>P. sojae</i> than <i>P. sansomeana.</i> Differentially expressed genes (DEGs) relative to mycelial samples were more pronounced for <i>P. sojae</i> than for <i>P. sansomeana</i>. More than a hundred genes were significantly upregulated across all three <i>P. sansomeana</i> isolates for all three time points. These included genes associated with cell wall degradation, jacalin-like lectin, NmrA-like family, one RxLR, and amino acid auxin permease family. For <i>P. sansomeana</i>, more genes annotated as crinkling- and necrosis-inducing were downregulated, and fewer necrosis-inducing peptides were upregulated compared with <i>P. sojae</i>, which could explain in part the difference in necrosis symptom development between the two species. Additionally, <i>P. sojae</i> had more DEGs associated with pathogenicity than the most aggressive <i>P. sansomeana</i> isolate. Several key defense pathways were upregulated in soybean earlier in response to the three <i>P. sansomeana</i> isolates than to <i>P. sojae</i>, including glucosinolate and glutathione biosynthesis, sulfur and tropane, and piperidine and pyridine alkaloid metabolism, which may also explain the reduced lesion sizes. These results provide a framework for using effector screening to select for effective host resistance against populations of both <i>P. sansomeana</i> and <i>P. sojae</i>.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":"PHYTO12250395R"},"PeriodicalIF":3.4,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148309071","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}