Phytopathology最新文献

{"title":"A Device for Computer Vision Analysis of Fungal Features Outperforms Quantitative Manual Microscopy by Experts in Discerning a Host Resistance Locus.","authors":"Surya Sapkota, Dani Martinez, Anna Underhill, Li-Ling Chen, David Gadoury, Lance Cadle-Davidson, Chin-Feng Hwang","doi":"10.1094/PHYTO-01-25-0033-R","DOIUrl":"https://doi.org/10.1094/PHYTO-01-25-0033-R","url":null,"abstract":"<p><p>Accurate, quantitative phenotyping aids the discovery of quantitative trait loci (QTL), particularly QTL with minor effects. Previously, we optimized replicated precision phenotyping of mapping families after inoculation of leaf discs with the grapevine powdery mildew pathogen (<i>Erysiphe necator</i>). Pathogen colonies were stained, and hyphal density was estimated using hyphal transects. This approach outperformed field evaluations and other controlled phenotyping methods but required one or two person-months of microscopy per experiment to evaluate resistance across 300 host genotypes. More recently, we combined advanced macrophotography, robotic sample positioning, and convolutional neural networks (CNNs) to produce a high-throughput phenotyping device, which was modified and commercialized as 'Blackbird'. Here, that device was tested for non-destructive image collection and computer vision quantification of foliar grapevine powdery mildew. Blackbird outpaced manual microscopy up to 60-fold and non-destructively generated time-series segregating phenotypes from 2 to 9 days post-inoculation (dpi). Paired analysis of these phenotypes with RNase H2-amplicon sequencing (rhAmpSeq) haplotype markers targeting the <i>Vitis</i> core genome detected <i>REN13</i> on chromosome 8. Genetic analysis of Blackbird CNN data explained a greater proportion of the phenotypic variance via hyphae at 4- dpi (24.5%) and conidia at 9- dpi (24.0%) than manual microscopy at 8- dpi (15.8%). As a moderate-effect resistance locus in the widely planted resistant variety 'Norton', which already produces commercial wine quality, <i>REN13</i> could significantly delay epidemics and could be useful in grape breeding programs to increase the durability of stronger resistance loci (eg, <i>RUN1</i>, <i>REN4</i> or <i>REN12</i>) in resistance gene stacks, while maintaining fruit quality.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143764726","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":"Transcriptome Response of <i>Rosa roxburghii</i> Fruit to Top-Rot Disease and Functional Analysis of <i>RrHSP18.1</i> in Top-Rot Disease Resistance.","authors":"Minggui Li, Min Lu, Xiaomao Wu, Huaming An","doi":"10.1094/PHYTO-01-25-0015-R","DOIUrl":"https://doi.org/10.1094/PHYTO-01-25-0015-R","url":null,"abstract":"<p><p>Top-rot disease (TRD) in <i>Rosa roxburghii</i> fruit is caused by <i>Colletotrichum fructicola</i>. TRD has emerged as a significant concern due to its frequent occurrence and cause of substantial economic losses. To understand the transcriptome response to TRD infection and identify candidate genes involved in TRD resistance, four critical time points (0, 24, 72, and 120 hpi) fruit tissues inoculated with TRD pathogen were selected for RNA-seq. A total of 1,890 differentially expressed genes (DEGs) were identified from the transcriptome data, including 1,051 upregulated and 839 downregulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that they were primarily involved in oxidoreductase activity and the synthesis and metabolism secondary metabolites. Many putative transcription factor families such as MYB, bHLH, AP2-EREBP, NAC, and WRKY were also identified as being positively responsive to TRD infestation. Among the upregulated genes, <i>RrHSP18.1</i> exhibited the strongest response to TRD. Transient overexpression and gene silencing demonstrated that <i>RrHSP18.1</i> positively regulated TRD resistance in <i>R. roxburghii</i> fruit, partially through promoting the expression of antioxidant-related genes and enhancing their enzyme activities. Collectively, the results facilitated a better understanding of the transcriptional response to TRD and offered candidate genes for developing <i>R. roxburghii</i> germplasm resource with improved TRD resistance.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143753371","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":"Deciphering the Mechanisms That Regulate Variability in Induced Systemic Resistance Among Tomato Genotypes.","authors":"Jane Marian Luis, Amit K Jaiswal, Tesfaye D Mengiste, James R Myers, Lori A Hoagland","doi":"10.1094/PHYTO-07-24-0240-R","DOIUrl":"https://doi.org/10.1094/PHYTO-07-24-0240-R","url":null,"abstract":"<p><p>Tomato responds to induced systemic resistance (ISR) by the beneficial fungus <i>Trichoderma harzianum</i> against foliar pathogens in a genotype specific manner. This study investigates the mechanisms underlying these differences using the foliar pathogen <i>Botrytis cinerea</i> and RNA-seq. <i>Solanum pimpinellifolium</i> LA 1589 (responsive) and <i>S. lycopersicum</i> cv. Wisconsin 55 (unresponsive) were treated with <i>T. harzianum</i> before inoculation with <i>B. cinerea</i> to characterize differences in priming capabilities. The LA 1589 <i>T. harzianum</i>-treated samples exhibited reduced disease lesion area, increased plant height, and higher root biomass compared to the non-treated control. Conversely, the Wisconsin 55 <i>T. harzianum</i>-treated samples did not show the same response. To understand the molecular basis of this differential response, temporal gene expression patterns were compared between genotypes. Genes and Gene Ontology terms associated with responses to autophagy, hypersensitive response, as well as auxin, brassinosteroid (BR), ethylene (ET), flavonoid, jasmonic acid (JA), phenylalanine, salicylic acid (SA), and sterol metabolic processes were uniquely enriched in at least one genotype × <i>T. harzianum</i> × <i>B. cinerea</i> treatment combination. Upregulation of genes associated with the BR, phenylpropanoid, and JA/ET signaling pathways, along with downregulation of genes related to the SA signaling pathway were identified as key factors to prime the ISR-responsive genotype against <i>B. cinerea</i>. These findings provide valuable insights into how to improve the efficacy of <i>Trichoderma</i>-based biocontrol strategies, and provide foundation for the development of more effective approaches to select genotypes that can better respond to beneficial microbes to obtain improved growth traits and heightened resistance against tomato pathogens.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143753434","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":"The First Molecular Characterization of <i>Solanum Lycopersicum</i>-<i>Phytophthora cinnamomi</i> Rands Phytopathosystem: The Essential Role of Pectin.","authors":"Lucía Del Castillo-González, César Poza-Carrión, Serine Soudani, Noelia de la Cruz-Gómez, María Fé Andrés, Azucena González-Coloma, José Antonio Manzanera, Marta Berrocal-Lobo","doi":"10.1094/PHYTO-01-25-0022-R","DOIUrl":"https://doi.org/10.1094/PHYTO-01-25-0022-R","url":null,"abstract":"<p><p><i>Phytophthora cinnamomi</i> is a destructive phytopathogen responsible for crown rot, trunk canker, and root rot in over 5,000 plant species worldwide. Despite its significant impact, the molecular interactions between this oomycete and host plants are not well understood. This study aimed to investigate the physiological and molecular responses of <i>Solanum lycopersicum</i> (tomato) to <i>Phytophthora cinnamomi</i> infection. The initial defense response in tomato seeds included producing reactive oxygen species (ROS) and callose deposition. Screening of commercial tomato varieties revealed varying levels of susceptibility, with the variety Marmande exhibiting heightened vulnerability. Three days post-inoculation, Marmande showed increased expression of genes associated with ROS generation, and biosynthesis pathways for phenylpropanoids and flavonoids. Additionally, 850 genes related to cell wall remodeling, including those involved in lignin biosynthesis and pectin methyl esterase inhibitors (PMEIs), were significantly upregulated. Seven days post-inoculation, a stronger transcriptional response was observed, with activation of ethylene (ET) and jasmonic acid (JA) signaling pathways, while salicylic acid (SA) showed minimal activity. Metabolomic analysis of infected roots revealed elevated levels of metabolites linked to lycopene, flavonoids, and phenylpropanoids. Furthermore, infected roots exhibited a significant reduction in pectin levels, which was corroborated by in vitro assays showing zoospore-mediated pectin degradation. These results suggest that the degradation of root pectin is a key mechanism facilitating zoospore invasion in susceptible tomato hosts. This study provides new insights into the molecular mechanisms underlying host-pathogen interactions and identifies potential targets for managing <i>Phytophthora cinnamomi</i>-induced crop diseases.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650005","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":"A Novel QTL on Chromosome 7D Derived from <i>Aegilops tauschii</i> Confers Moderate Field Resistance to Wheat Blast.","authors":"Xinyao He, Cong Li, Masahiro Kishii, Soichiro Asuke, Mohammad R Kabir, Krishna K Roy, Roberto Butron, Aakash Chawade, Yukio Tosa, Pawan K Singh","doi":"10.1094/PHYTO-01-25-0018-R","DOIUrl":"https://doi.org/10.1094/PHYTO-01-25-0018-R","url":null,"abstract":"<p><p>Wheat blast is a devastating disease in the tropical and subtropical regions of South America and has recently spread to Bangladesh and Zambia. Host resistance to this disease has primarily relied on the 2NS/2AS translocation, making it crucial to identify and utilize novel sources of resistance. In the current study, a recombinant inbred line population consisting of 345 BC₁F₄ progenies was generated, using the susceptible wheat genotype 'Gladius' as the female and recurrent parent, and the resistant <i>Aegilops tauschii</i> line 'KU-2097' as the male parent. Field phenotyping was conducted at two locations in Bolivia and one in Bangladesh, each with two sowing dates, during the 2022-23 or 2023 cropping cycles. Genotyping was performed using DArTseq® technology. QTL mapping identified a major and consistent QTL on the long arm of chromosome 7D, designated as <i>Qwb.cim-7D</i>, which explained 7.7 to 50.6% of the phenotypic variation across different experiments. The DArTseq markers in the QTL region were converted to KASP markers, enabling the precise mapping of this QTL to a genomic region between 619.90 and 625.61 Mb, flanked by the KASP markers <i>K3222157</i> and <i>K1061589</i>. This novel QTL, along with its flanking markers, could be valuable for breeding programs targeting wheat blast resistance.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143650003","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 of Novel Basil Downy Mildew Resistance Genes Using <i>De Novo</i> Comparative Transcriptomics.","authors":"Kelly S Allen, Gregory A DeIulio, Robert Pyne, Jacob Maman, Li Guo, Rebecca Lyon, Eric T Johnson, Robert Wick, James E Simon, Anne Gershenson, Li-Jun Ma","doi":"10.1094/PHYTO-11-24-0369-R","DOIUrl":"https://doi.org/10.1094/PHYTO-11-24-0369-R","url":null,"abstract":"<p><p>Sweet basil (<i>Ocimum basilicum</i> L.) production is threatened by the oomycete pathogen <i>Peronospora belbahrii</i>, causing basil downy mildew (BDM). BDM-resistant cultivar 'Mrihani' (MRI) was identified in a germplasm screen, and bred with BDM-susceptible 'Newton' (SB22) to produce resistant cultivars, but the molecular mechanisms conferring resistance in MRI and the progeny remained unknown. A comparative transcriptomic approach was used to identify candidate resistance genes and potential mechanisms for BDM resistance. To differentiate the host-pathogen interactions in resistant and susceptible plants, RNA samples from BDM-infected MRI and SB22 plants were harvested at four time points during the first three days of infection, with mock-inoculated controls for both genotypes. Three categories of genes uniquely transcribed in the resistant MRI upon pathogen challenge were identified: nucleotide-binding leucine-rich repeat proteins (NLRs), multi-functional receptor-like kinases (RLKs), and secondary metabolic enzymes. Validation of the top resistance candidate NLR gene confirmed its unique presence in MRI and two of four resistant MRIxSB22 F₂ progeny. In MRI, pathogen challenge also induced differential regulation in members of the salicylic acid synthesis pathway, suggesting its role in BDM resistance. Overall, our study demonstrates the utility of <i>de novo</i> comparative transcriptomics to identify resistance genes and mechanisms in non-model crops.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143624626","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":"Effect of Weather Variables on the Inoculum of <i>Diaporthe amygdali</i> Causal Agent of Twig Canker and Shoot Blight in Almond Orchards.","authors":"Francisco Beluzán, Antonio Vicent, David Conesa, Felipe Torrentí, Diego Olmo, Maela León, Paloma Abad-Campos, Josep Armengol","doi":"10.1094/PHYTO-02-25-0047-R","DOIUrl":"https://doi.org/10.1094/PHYTO-02-25-0047-R","url":null,"abstract":"<p><p><i>Diaporthe amygdali</i> is the causal agent of twig canker and shoot blight disease on almond. The main objective of this study was to elucidate the effect of weather variables on the <i>D. amygdali</i> inoculum in almond orchards in Mediterranean conditions. For that purpose, a quantitative PCR (qPCR) assay for the detection and quantification of <i>D. amygdali</i> was developed. This methodology was used to detect and quantify inoculum of <i>D. amygdali</i> in spore traps placed at two almond orchards from different locations in two growing seasons (2019 to 2020 and 2020 to 2021). Weather variables were also recorded. Two-part Hurdle models, which include a qualitative part (Bernoulli), with a binary response, and a quantitative part (Gamma), were used to study the relationships of DNA concentration of <i>D. amygdali</i> on the traps with weather variables. The temperature effect was related to the daily thermal amplitude; narrower thermal ranges increased DNA detection, while wider thermal ranges reduced DNA concentration. Days with average relative humidity higher than 80% had a negative effect on the concentration of <i>D. amygdali</i> DNA. Rainfall had a positive influence on both parts of the model, confirming the contribution of precipitation in the abundance of inoculum. Finally, wind speed positively influenced both parts of the models in both growing seasons. The relationships between weather variables and inoculum of <i>D. amygdali</i> will assist to develop a decision support system to optimize the management of twig canker and shoot blight disease on almond.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605481","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 Three Resistance-Breaking Isolates of Sugarcane Mosaic Virus from Rwanda and Implications for Maize Lethal Necrosis.","authors":"Jennifer R Wilson, Kristen J Willie, Lucy R Stewart, Margaret G Redinbaugh, Erik W Ohlson","doi":"10.1094/PHYTO-07-24-0227-R","DOIUrl":"https://doi.org/10.1094/PHYTO-07-24-0227-R","url":null,"abstract":"<p><p>Maize lethal necrosis (MLN) is a devastating disease of maize caused by synergy between two viruses: maize chlorotic mottle virus (MCMV) and a potyvirus, often sugarcane mosaic virus (SCMV). Throughout the 2010s, severe MLN outbreaks occurred in East Africa including Kenya, Rwanda, and Ethiopia. Previous studies have shown extensive sequence diversity among SCMV isolates collected from this region. In this study, we assessed how this diversity may alter virulence by screening a panel of maize near isogenic lines containing different combinations of major potyvirus resistance loci with diverse SCMV isolates collected from Rwanda. We discovered that the three isolates tested overcame all three potyvirus resistance loci even when stacked, including one isolate that asymptomatically infected all resistant lines tested. To understand how SCMV virulence may contribute to MLN, each SCMV isolate was co-inoculated with MCMV on a panel of SCMV and MCMV resistant maize lines. No significant differences in MLN severity were observed for the isolates from Rwanda compared to the reference SCMV isolates, indicating that increased virulence in SCMV single infection did not necessarily correlate with increased MLN severity in co-infection with MCMV. At least two potyvirus resistance loci were needed to reduce MLN severity and combining SCMV and MCMV resistance was most effective. Remarkably, in some cases, co-infection with MCMV facilitated SCMV infection of potyvirus resistant lines that SCMV could not infect alone. These results underscore the challenges of developing durable MLN resistance and highlight the importance of incorporating strong, multigenic potyvirus resistance into MLN resistance breeding programs.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143606253","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":"Novel Non-Destructive Detection Methods for <i>Bretziella fagacearum</i> in Northern Red Oak and Chestnut.","authors":"Karandeep Chahal, Ethan J Wachendorf, Laura A Miles, Adam M Grove, Martin I Chilvers, Timothy D Miles","doi":"10.1094/PHYTO-08-24-0253-R","DOIUrl":"https://doi.org/10.1094/PHYTO-08-24-0253-R","url":null,"abstract":"<p><p>Oak wilt, caused by the fungal pathogen <i>Bretziella fagacearum</i>, spreads via root grafts and insect vectors, threating oaks (<i>Quercus</i> spp.) and chestnuts (<i>Castanea</i> spp.) in the United States. Detection and management of <i>B. fagacearum</i> are crucial, as oak wilt can devastate forested and urban ecosystems. However, diagnosing oak wilt presents challenges and requires laboratory confirmation due to symptom similarities with other stressors. Common detection methods also have limitations. In this study, we optimized and validated an existing TaqMan real-time PCR assay, comparing it with a culture-based method and using nested PCR as gold standard. We also developed a novel non-destructive sampling technique. Our optimized real-time PCR assay demonstrated a consistent 100% detection rate and accuracy across all branch sapwood samples. In contrast, the culture-based method varied significantly, achieving 100% detection rate and accuracy only for fresh samples displaying sapwood discoloration. In the absence of sapwood discoloration, the culture detection rate and accuracy were 80% and 90%, respectively. For dry samples, these rates decreased significantly to 22% and 52%. The novel non-destructive sampling method used leaf petioles of fallen leaves to detect <i>B. fagacearum</i> from two tree hosts, using both optimized real-time PCR and culture-based methods. Our real-time PCR consistently outperformed the culture-based method, regardless of symptom severity in leaf samples. The real-time PCR offers improved efficiency, specificity, sensitivity, and turnaround time compared to nested PCR and culture-based methods. Our findings highlight the potential of detecting vascular-inhabiting pathogens from leaf petiole samples, particularly in scenarios requiring non-destructive sampling and high-throughput screening.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605495","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":"Preserving the Biologically Coherent Generic Concept of <i>Phytophthora</i>, 'Plant Destroyer'.","authors":"Clive M Brasier, Niklaus J Grünwald, Tyler B Bourret, Francine Govers, Bruno Scanu, David E L Cooke, Tanay Bose, David L Hawksworth, Z Gloria Abad, M Victoria Albarracin, Wael Alsultan, Astrid E Altamirano-Junqueria, Arild R Arifin, Matthew J Arnet, Herbert Dustin R Aumentado, József Bakonyi, Wei H Belisle, Alessandra Benigno, John C Bienapfl, Guillaume J Bilodeau, Jaime E Blair, Leticia Botella, Andrea Brandano, Santa Olga Cacciola, Ignazio Carbone, Vanina L Castroagudin, Narayan Chaendaekattu, Jonathan D Consford, Tamara Corcobado, Paul A Covey, Hazel A Daniels, Antonia Deidda, Anne E Dorrance, Erika N Dort, Andre Drenth, Fryni Drizou, Edouard Evangelisti, Sebastian N Fajardo, Yufeng Fang, Christopher M Ference, Susan J Frankel, Erica M Goss, David I Guest, Giles E St J Hardy, Anna R H Harris, Mehari Desta Hawku, Kurt Heungens, Chuanxue Hong, Ian J Horner, Marília Horta Jung, Olumayowa J Iyanda, Brittney-Aidan Jamieson, Steven N Jeffers, Howard S Judelson, Muhammad Junaid, Eleni Kalogeropoulou, Sophien Kamoun, Seogchan Kang, Takao Kasuga, Tomáš Kudláček, Jared LeBoldus, Christopher A Lee, DeWei Li, Alejandro K Llanos, Horacio D Lopez-Nicora, Helena Machado, Cristiana Maia, Kajal Mandal, Patricia Manosalva, Frank N Martin, Michael E H Matson, Rebecca L McDougal, John M McDowell, Richard W Michelmore, Ivan Milenković, Salvatore Moricca, Reza Mostowfizadeh-Ghalamfarsa, Zoltán Á Nagy, Ekaterina V Nikolaeva, Paula Ortega-López, Trudy Paap, Camilo H Parada-Rojas, Francesca Peduto Hand, Ana Perez-Sierra, Martin Pettersson, Pramod Prasad, Alina S Puig, Milica Raco, Nasir A Rajput, Jean B Ristaino, Suzanne Rooney-Latham, Michael F Seidl, Simon F Shamoun, Alejandro Solla, Christoffel F J Spies, Martha A Sudermann, Tedmund J Swiecki, Miaoying Tian, Sucheta Tripathy, Seiji Uematsu, Kris Van Poucke, Aikaterini E Vichou, Monika Walter, Joan F Webber, Nari M Williams, Michael J Wingfield, Dhananjay Yadav, Xiao Yang, Thomas Jung","doi":"10.1094/PHYTO-11-24-0372-LE","DOIUrl":"https://doi.org/10.1094/PHYTO-11-24-0372-LE","url":null,"abstract":"<p><p><i>Phytophthora</i> is a long-established, well known and globally important genus of plant pathogens. Phylogenetic evidence has shown that the biologically distinct, obligate biotrophic downy mildews evolved from <i>Phytophthora</i> at least twice. Since, cladistically, this renders <i>Phytophthora</i> 'paraphyletic', it has been proposed that <i>Phytophthora</i> evolutionary clades be split into multiple genera (Runge et al. 2011; Crous et al. 2021; Thines et al. 2023; Thines 2024). In this letter, we review arguments for the retention of the generic name <i>Phytophthora</i> with a broad circumscription made by Brasier et al. (2022) and by many delegates at an open workshop organized by the American Phytopathological Society. We present our well-considered responses to this proposal in general terms and to the specific proposals for new genera; together with new information regarding the biological properties and mode of origin of the <i>Phytophthora</i> clades. We consider that the proposals for new genera are mostly non-rigorous and not supported by the scientific evidence. Further, given (1) the apparent lack of any distinguishing biological characteristics (synapomorphies) between the <i>Phytophthora</i> clades; (2) the fundamental monophyly of <i>Phytophthora</i> in the original Haeckelian sense; (3) the fact that paraphyly is not a justification for taxonomic splitting; and (4) the considerable likely damage to effective scientific communication and disease management from an unnecessary break-up of the genus, we report that Workshop delegates voted unanimously in favour of preserving the current generic concept and for seeking endorsement of this view by a working group of the International Commission on the Taxonomy of Fungi.</p>","PeriodicalId":20410,"journal":{"name":"Phytopathology","volume":" ","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143605498","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}