Plant disease最新文献

{"title":"qPCR-Based Quantification As A Tool For Genetic Selection And Yield-Stable Breeding Against Restricted Phloem Pathogens In Potato.","authors":"Salma Benaouda, David Alexander Schuch, David Loeffler, Kwang-Zin Lee, Christian Lang","doi":"10.1094/PDIS-05-26-0969-RE","DOIUrl":"https://doi.org/10.1094/PDIS-05-26-0969-RE","url":null,"abstract":"<p><p>The emerging phloem‑restricted pathogens Candidatus Arsenophonus phytopathogenicus (ARSEPH) and Candidatus Phytoplasma solani (PHYPSO), transmitted by the planthopper Pentastiridius leporinus, threaten European potato (Solanum tuberosum L.) production. This study used quantitative real‑time PCR (qPCR) to quantify ARSEPH and PHYPSO in 40 varieties grown at two field locations in southwest Germany under high natural P. leporinus pressure. Tuber assays revealed near‑complete infection (95.7-100%), dominated by co‑infections, with ARSEPH more prevalent and generally reaching higher copy numbers than PHYPSO. ANOVA showed that ARSEPH load was primarily genotype‑dependent, with stable varietal rankings across locations, whereas PHYPSO titres were strongly affected by both location and genotype and exhibited a pronounced genotype × location interaction. Processing varieties carried higher ARSEPH loads than ware potatoes, while maturity class did not explain clear differences in pathogen titre. Spearman correlations indicated that increased pathogen load was statistically associated with earlier symptom expression, accelerated canopy senescence, and a shift from marketable (35-65 mm) to undersized tubers, resulting in moderate but consistent reductions in net yield and increased rubbery tuber incidence; P. leporinus abundance was tightly linked to canopy yellowing and yield loss. These findings support the use of qPCR‑derived pathogen copy number as a robust quantitative trait for assessing varietal susceptibility under high infection pressure and argue for its integration into potato breeding and integrated management strategies in regions facing rising ARSEPH and PHYPSO pressure.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075276","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":"Occurrence and field-level co-occurrence of <i>Heterodera</i> spp., <i>Verticillium longisporum</i>, and <i>Pectobacterium</i> spp. in highland kimchi cabbage fields in South Korea.","authors":"Sohee Park, Balaraju Kotnala, Sung Kee Hong, Yong Hwan Lee, Sekeun Park, Mi Hyun Lee, Hyoung-Rai Ko, Heonil Kang","doi":"10.1094/PDIS-08-26-1548-SC","DOIUrl":"https://doi.org/10.1094/PDIS-08-26-1548-SC","url":null,"abstract":"<p><p>This study investigated the occurrence and field-level co-occurrence of cyst nematodes, <i>Verticillium longisporum</i>, and <i>Pectobacterium</i> spp. in highland kimchi cabbage fields in South Korea during 2023-2024. Three major pathogen groups and associated diseases were identified at the species level: cyst nematodes (CN; <i>Heterodera trifolii</i> and <i>H. schachtii</i>), <i>Verticillium</i> wilt caused by <i>V. longisporum</i> (VW), and bacterial soft rot caused by <i>Pectobacterium carotovorum</i> and <i>P. brasiliense</i> (BSR). Among 97 surveyed fields, individual detection frequencies for CN, VW, and BSR were 31%, 21%, and 54%, respectively. The simultaneous detection of CN, VW, and BSR was the most frequent field-level co-occurrence pattern, occurring in 29% of fields in which at least one target pathogen or associated disease was detected. This co-occurrence pattern was mainly observed in Taebaek and Samcheok, whereas <i>V. longisporum</i> was detected only in CN-associated fields. These findings document the regional occurrence and field-level co-occurrence of major pathogen groups in highland kimchi cabbage fields and provide a basis for future studies to determine whether these pathogens interact to influence disease severity.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149075286","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":"Implementing Honey Bee Surveillance for the Detection of Avocado Sunblotch Disease in California.","authors":"Mehdi Kamali, Xiaoqian Jiang, Jiayi Xu, Ben Faber, Hamutahl Cohen, Yiding Zhong, Chuanhua Duan, Ke Du, Fatemeh Khodadadi","doi":"10.1094/PDIS-06-26-1193-RE","DOIUrl":"https://doi.org/10.1094/PDIS-06-26-1193-RE","url":null,"abstract":"<p><p>Avocado sunblotch viroid (ASBVd) represents a complex and significant hurdle for the avocado industry and growers. The viroid's uneven distribution within host tissues makes traditional leaf-based indexing logistically intensive and prone to sampling errors. This study evaluates a honey bee-mediated surveillance framework as a scalable alternative for orchard monitoring. Beehives were strategically positioned across four commercial orchards in Southern California, located directly under the canopy and at distances of 100 and 200 meters from confirmed infected trees. A total of 83 samples, comprising foragers, hive-bound workers, and stored pollen, were processed for RNA extraction and reverse transcription to cDNA and then screened using an integrated platform of Recombinase Polymerase Amplification (RPA), CRISPR-Cas12a, and solid-state nanopore-array sensing. Results were further validated and quantified via droplet digital PCR (ddPCR). ASBVd was successfully detected in both honey bee and pollen samples collected near and 100 m away from infected trees, with stored pollen exhibiting a significantly higher prevalence and viral titer. The RPA-CRISPR-nanopore platform identified nine pollen and one bee-positive samples with viroid loads down to 1.57 copies/µL, all of which were confirmed by ddPCR. Additionally, we used ddPCR to identify three more low-titer bee and pollen samples with viroid loads down to 0.52 copies/µL. This dual-detection framework combines RPA-CRISPR-nanopore for rapid field screening with ddPCR for sensitive confirmation of low-titer samples. By using honey bees as efficient biological sensors, this system offers a scalable proof-of-concept approach for monitoring ASBVd in avocado orchards.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149069974","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":"Introgression of Septoria Leaf Spot Resistance from Wild <i>Solanum</i> Species into Cultivated Tomato via Ovule Rescue, Bridging Backcrosses, and Identification of Candidate Resistance Loci.","authors":"Inty Omar Hernandez De Lira, Estefania Tavares Flores, Mannon Gallegly, Mahfuzur Rahman, Vagner Benedito","doi":"10.1094/PDIS-03-26-0581-RE","DOIUrl":"https://doi.org/10.1094/PDIS-03-26-0581-RE","url":null,"abstract":"<p><p>Septoria leaf spot (SLS), caused by <i>Septoria lycopersici</i> Speg., is an important and increasingly prevalent foliar disease of tomato (<i>Solanum lycopersicum</i> L.) with no commercially resistant cultivars available. We screened 22 cultivated and wild accessions against a prevalent <i>S. lycopersici</i> isolate (WV21-1) and identified <i>S. peruvianum</i> LA2744 and <i>S. corneliomulleri</i> LA1910 as highly resistant (score 1 on a 1-to-5 scale), with <i>S. arcanum</i> LA1984 as resistant (score 2), whereas cultivated accessions scored 4 to 5. Using an optimized ovule rescue protocol with a 25-to-35-day rescue window after pollination, we recovered five confirmed interspecific F₁ hybrids from 34,475 cultured ovules. Hybridity was validated with a 24-marker genome-wide cleaved amplified polymorphic sequence (CAPS) panel, which also identified two self-escapes. Most F₁ plants exhibited post-zygotic incompatibility, preventing direct backcrossing. Using of cv. Micro-Tom as a bridging parent overcame this barrier, yielding approximately 17 BC₁ plants per 100 pollinations. Segregating populations displayed continuous SLS score distributions and high broad-sense heritability (H²=0.80-0.84), consistent with quantitative resistance. Composite interval mapping identified putative resistance-associated regions. In the <i>S.arcanum</i>-derived BC₁ (n=169), a candidate locus on chromosome 8, with the wild allele conferring resistance, was significant in the multiple QTL model (P=0.003; 4.9% variance) but did not exceed the genome-wide threshold. In the <i>S. peruvianum</i>-derived ΨF2 (n=354), no locus reached significance. Beyond mapping, this study delivers an integrated, reproducible pipeline (donor screening, species-specific ovule rescue, low-cost CAPS-based hybrid validation, and Micro-Tom bridging) that converts wild SLS resistance into validated, backcross-ready material and nominates chromosome 8 for fine-mapping.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149069966","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":"Etiology, Molecular Diagnosis, and Fungicide Screening of the Newly Characterized Atractidochium Needle Spot Disease on <i>Pinus thunbergii</i> in Taiwan.","authors":"Yu-Ming Huang, Chia-Lin Chung","doi":"10.1094/PDIS-12-25-2491-RE","DOIUrl":"10.1094/PDIS-12-25-2491-RE","url":null,"abstract":"<p><p><i>Pinus thunbergii</i> is an important ornamental species in Taiwan; however, its needles frequently develop yellowish spots that have long been attributed to Lophodermium needle cast. From 2023 to 2025, surveys conducted across 13 sites and 52 sampling events consistently associated these lesions with a slow-growing Basidiomycetous fungus identified as <i>Atractidochium hillariae</i> based on morphology and multilocus phylogenetic analyses (internal transcribed spacer [ITS], small subunit rRNA [SSU], and large subunit rRNA [LSU]). Previously reported only as an endophyte of <i>Pinus taeda</i> in the United States, <i>A</i>. <i>hillariae</i> was the dominant fungus isolated from yellowish-spot needles of <i>P</i>. <i>thunbergii</i>, whereas <i>Lophodermium</i> spp. predominated in fallen, dead needles. Detached twig and field inoculations with <i>A</i>. <i>hillariae</i> reproduced restricted bright yellow lesions with reddish-brown centers identical to field symptoms, and the pathogen was successfully reisolated, fulfilling Koch's postulates. The new disease is designated as \"Atractidochium needle spot disease.\" Monthly monitoring revealed that disease severity increased from November, peaked in April to May, and declined in June to July. A newly developed <i>A</i>. <i>hillariae</i>-specific PCR assay targeting the ITS region enabled sensitive (limit of detection, 25 fg μl^-1) and specific detection from field samples. In vitro mycelial growth inhibition assays demonstrated that pyraclostrobin and tebuconazole exhibited the strongest inhibition (EC₅₀ < 0.1 mg kg^-1), suggesting their potential for chemical control. Future research on the disease cycle, host range, and fungicide efficacy in planta will facilitate the development of effective management strategies. It is also worth exploring whether <i>A</i>. <i>hillariae</i> functions as an opportunistic endophyte capable of shifting from a latent to a pathogenic phase under certain conditions.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":"PDIS12252491RE"},"PeriodicalIF":2.8,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147778416","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":"Unraveling the Dynamics of Tar Spot Epidemics in Corn Fields: A Data-Driven Framework for Disease Development and Surveillance.","authors":"Brenden Z Lane, Carlos C Góngora-Canul, Joaquín Guillermo Ramírez-Gil, C D Cruz","doi":"10.1094/PDIS-07-25-1506-RE","DOIUrl":"10.1094/PDIS-07-25-1506-RE","url":null,"abstract":"<p><p>Tar spot, caused by <i>Phyllachora maydis</i> Maubl., has significantly impacted U.S. corn production since its first detection in 2015. The elusive nature of this fungus has hindered advancement in disease characterization, especially pertaining to its spatiotemporal development. This study provides an in-depth analysis of field-scale epidemics by considering both temporal and vertical dynamics to ascertain the spatiotemporal intensification of this disease. The analysis involved generating high-resolution severity data across four growing seasons (2021 to 2024) in two production-style corn fields in northwest Indiana. We then applied population growth models and Markov chains to parameterize the temporal and vertical dynamics of tar spot progression within the corn canopy. From this, we found three distinct epidemiological phases: an establishment phase characterized by sporadic onset with <0.5% severity, a lag phase with widespread low severity (0.5 to 1%), and an exponential phase with rapid severity increases exceeding 40% in some cases. Beyond the conventional \"bottom-up\" paradigm, we observed diverse infection-like patterns influenced by canopy position, onset timing, and corn growth stage. Exponential growth models described severity intensification with an average apparent infection rate of 0.20/day, which was applicable across canopy positions, locations, and years. An aggregated Markov chain model, built from the 2021 to 2023 data, accurately estimated the 2024 epidemic's vertical-temporal progression and thus validated the framework developed from this study. Ultimately, this approach supports improved surveillance for targeted management by establishing a foundation for real-time detection and probabilistic modeling to aid in the enhancement of crop production.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":"PDIS07251506RE"},"PeriodicalIF":2.8,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147639498","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":"Detection and Distribution of <i>Fusarium oxysporum</i> f. sp. <i>fragariae</i> Race 2 in California.","authors":"Peter M Henry, Christine Jade Dilla-Ermita, Polly Goldman, Jose H Jaime, Kayla Pennerman, Hanane Stanghellini, Steve Koike, Samantha Simard, Andrew Molinar, Shashika S Hewavitharana, Gerald J Holmes, Thien Ho, Nicholas LeBlanc","doi":"10.1094/PDIS-01-26-0233-RE","DOIUrl":"10.1094/PDIS-01-26-0233-RE","url":null,"abstract":"<p><p>Fusarium wilt of strawberry is a widespread disease controlled through genetic resistance to <i>Fusarium oxysporum</i> f. sp. <i>fragariae</i> (<i>Fof</i>) race 1 conferred by the <i>FW1</i> locus. In 2022, a novel race called CA <i>Fof</i> race 2 was identified in Oxnard, California (CA), that can overcome <i>FW1</i> resistance and cannot be identified using published molecular diagnostic assays. To understand the prevalence and enable early detection of the novel CA <i>Fof</i> race 2, this research developed strain-specific qPCR and recombinase polymerase amplification (RPA) diagnostic assays and applied them to survey CA <i>Fof</i> race 2 in strawberry. A candidate locus was identified through alignment of reads from off-target isolates to genome assemblies of two virulent CA <i>Fof</i> race 2 isolates. Diagnostic qPCR and RPA tests were validated using target and off-target DNA. The RPA was validated in two laboratories to confirm reproducibility and used to test 2,945 diagnostic samples collected in strawberry-growing areas of the United States of America, Canada, and Mexico. Both assays showed 100% specificity based on laboratory screening of DNA. The limit of detection was 100 fg of DNA for the qPCR assay and 1 pg for the RPA assay. The RPA assay identified 19 out of 2,945 samples as positive for CA <i>Fof</i> race 2, all from six fields around Oxnard, CA; these results were confirmed by subsequent isolations and qPCR. Outcomes of this research provide essential diagnostic tools for quantifying and identifying CA <i>Fof</i> race 2 and highlight the limited geographic distribution of this novel resistance-breaking strawberry pathogen.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":"PDIS01260233RE"},"PeriodicalIF":2.8,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147639521","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":"Characterization of Spartina Mottle Virus (SpMV) and Barley Yellow Striate Mosaic Virus (BYSMV) Infecting Green Foxtail (<i>Setaria viridis</i>) in France.","authors":"Thierry Candresse, Chantal Faure, Armelle Marais","doi":"10.1094/PDIS-02-26-0394-SC","DOIUrl":"10.1094/PDIS-02-26-0394-SC","url":null,"abstract":"<p><p>Analysis of French Poaceae pools collected in 2023 identified Spartina mottle virus (SpMV, <i>Phragmivirus spartinae</i>) infection in green foxtail (<i>Setaria viridis</i>). RNAseq of two plants yielded near-complete SpMV genomes and a complete barley yellow striate mosaic virus genome (BYSMV, <i>Betacytorhabdovirus hordei</i>). The novel SpMV genomes show only 79.3 to 80.4% nucleotide identity with those of German and U.S. isolates (92 to 92.6% amino acid identity), while the BYSMV sequence is 94% identical to the only complete BYSMV genome available. Besides providing novel information on the genetic variability of these two viruses, these results extend the known natural host range and distribution of SpMV.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":"PDIS02260394SC"},"PeriodicalIF":2.8,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147778358","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":"Geographic Isolates of Reniform Nematode Differ in Their Reproduction and Virulence.","authors":"Sagar Gc, John Mueller, Christopher McMahan, William Bridges, Kaitlyn Bissonnette, Christopher Saski, Churamani Khanal","doi":"10.1094/PDIS-02-26-0378-RE","DOIUrl":"10.1094/PDIS-02-26-0378-RE","url":null,"abstract":"<p><p>Management of the reniform nematode (<i>Rotylenchulus reniformis</i> Linford and Oliveira) in upland cotton (<i>Gossypium hirsutum</i> L.) continues to be a challenge primarily due to inconsistent performance of resistant genotypes. We hypothesize that diversity in reproduction and virulence in <i>R. reniformis</i> has contributed to the inconsistent performance of resistant cotton genotypes. <i>R. reniformis</i> isolates from Tennessee (TN), Alabama (AL), Mississippi (MS), Texas (TX), Louisiana (LA), Arkansas (AR), Florida (FL), South Carolina (SC), and Georgia (GA) were assessed for their reproduction and virulence on a resistant cultivar, DP 2141NR B3XF, and a susceptible cultivar, DP 2317 B3TXF. The AR isolate had the greatest reproduction factor (Rf) of 19.7, while the AL isolate had the lowest Rf of 3.3. Rfs of other isolates were intermediate. Up to 85% of reproductions were suppressed by the resistant cultivar relative to the susceptible cultivar. While plants inoculated with nematodes had lower root biomass than the noninoculated control, the degree of root biomass reduction varied by isolate, suggesting differing levels of virulence among <i>R. reniformis</i> isolates. The AR isolate reproduced the most and was the most virulent. The AL isolate reproduced the least and was less virulent. The AR, MS, TN, and LA isolates were the top four reproducing isolates, probably indicating a greater suitability of the Delta region for nematode reproduction. The correlation analysis indicated that up to 85% of variation in plant biomass was explained by nematode reproduction. These results suggest that resistance breeding programs in cotton must consider the diversity in <i>R. reniformis</i>.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":"PDIS02260378RE"},"PeriodicalIF":2.8,"publicationDate":"2026-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147639513","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":"Identification and Characterization of PVY^N-Wi Isolates Associated with External Tuber Necrosis in the San Luis Valley (Colorado): A New Challenge for Seed Potato Certification.","authors":"Peter Abrahamian, Samuel Grinstead, Crosley Kudla-Williams, Mohamad Chikh-Ali","doi":"10.1094/PDIS-02-26-0371-SR","DOIUrl":"https://doi.org/10.1094/PDIS-02-26-0371-SR","url":null,"abstract":"<p><p>Potato (Solanum tuberosum L.) is a major global staple crop, and potato virus Y (PVY) is one of the most economically important viruses affecting potato production worldwide. The San Luis Valley (SLV) produces approximately 95% of Colorado's potatoes and is the second-largest fresh potato-growing region in the United States. PVY is the leading cause of seed potato rejection in the SLV and has contributed to a sustained decline in certified seed potato production over the past two decades. The PVY population in Colorado is dominated by three strains: PVY^O, PVY^N-Wi, and PVY^NTN. PVY^N-Wi accounts for approximately 40% of PVY infections in the SLV and its impact on tuber quality remains poorly understood. During the 2023 and 2024 growing seasons, potato tubers exhibiting external necrosis and cracking were submitted to the Potato Pathology Program of the San Luis Valley Research Center for diagnosis. PVY^N-Wi was consistently identified in the symptomatic tubers. These results agree with previous studies demonstrating that external tuber necrosis, historically attributed to PVY^NTN, may also be associated with PVY^N-Wi, under field conditions. As PVY^N-Wi belongs to the O-serotype, it is not detected by the N-serotype specific antibodies used in seed certification programs to manage tuber necrotic strains of PVY. Consequently, the contribution of PVY^N-Wi to tuber quality losses in the SLV may be underestimated, highlighting the need to reassess PVY diagnostic and management strategies.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2026-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149025622","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}