Plant disease最新文献

{"title":"Systematic exploration, evaluation, and application of significant loci for Fusarium head blight resistance in wheat.","authors":"Peng Jiang, Lei Wu, Chang Li, Yongchao Hao, Yi He, Peng Zhang, Hongwei Wang, Xu Zhang","doi":"10.1094/PDIS-10-24-2115-RE","DOIUrl":"https://doi.org/10.1094/PDIS-10-24-2115-RE","url":null,"abstract":"<p><p>Fusarium head blight (FHB), a serious disease in wheat, causes significant reductions in grain yield and quality worldwide. Marker-assisted selection can provide an effective tool for improving FHB resistance. Although many quantitative trait loci associated with resistance to FHB have been reported, few loci are currently available in breeding programs. The middle and lower reaches of the Yangtze River in China are areas that historically have experienced FHB epidemics, so that some local varieties may contain some valuable genes providing FHB resistance. In this study, association mapping was performed using 103 local cultivated varieties, and a previous QTL mapping using a recombinant inbred line (RIL) population from two locally popular parents, specifically Ningmai 9 and Yangmai 158, was integrated to identify nine candidate intervals. The corresponding Kompetitive Allele Specific PCR markers associated with FHB resistance were successfully developed and validated in 611 breeding lines. Four loci, namely QFhb.jaas-2D, QFhb.jaas-3A, QFhb.jaas-5A.2, and QFhb.jaas-6D, proved to be significantly related to FHB resistance in addition to Fhb1, and they could provide good resistance to FHB in the absence of Fhb1; the combination of multiple loci could produce a more stable resistance. These five markers were then applied in 211 breeding lines, and many resistance lines were obtained with different combinations of resistance loci. Additionally, QFhb.jaas-3A proved to be a highly selected locus, and eight differential genes in its interval were identified by genome and transcriptome analysis. This study provides additional gene resources and materials that could be used in FHB resistance breeding in wheat.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710876","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":"Bittersweet Challenges: Postharvest Disease Management in Sugarbeet and Sweetpotato.","authors":"Carlos Morales, Kelly Avila, Usha Bhatta, Malick Bill, Collins Bugingo, Maria Camila Buitrago Acosta, Hunter Collins, Sandesh Dangi, Linda Hanson, Carly Hendershot, Shyam L Kandel, Jack Mecklin Mascarenhas, Rachel P Naegele, Camilo Parada-Rojas, Lindsey Thiessen, Sarah Jane Pethybridge, Kirsten Pollok, Jaime F Willbur, Lina Quesada-Ocampo","doi":"10.1094/PDIS-10-24-2214-FE","DOIUrl":"https://doi.org/10.1094/PDIS-10-24-2214-FE","url":null,"abstract":"<p><p>Root crops like sugarbeet and sweetpotato possess an aggregated value that sets them apart from other crops. This aggregated value includes not only their economic importance but also their high nutritional content, which can enhance global food security. However, the economic and nutritional value of these crops is significantly compromised by postharvest diseases, presenting major socio-economic challenges. Postharvest diseases, caused by various fungal and bacterial pathogens, affect crops during field growth, harvest, handling, and storage. Addressing these challenges requires improving several key aspects of disease management that are often lacking in postharvest pathosystems. These aspects include but are not limited to diagnostic methodologies, cultural practices, chemical control, host resistance, and pathogen monitoring among others. Emerging technologies and strategies from various fields offer promising solutions to these challenges. In this manuscript, we review new approaches to address common challenges in postharvest diseases of sugarbeet and sweetpotato. This review highlights important considerations for the implementation, modification, and creation of new approaches to maintain or increase the value of these commodities, which are threatened by postharvest diseases.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710862","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":"Efficacy of pruning-wound protectant fungicides for the management of <i>Botryosphaeria</i> canker and dieback of apple trees in Maule region, Chile.","authors":"Adrián Vinicio Valdez-Tenezaca, Mauricio A Lolas, Fernanda B Núñez, Bernardo Antonio Latorre, Lizel Mostert, Francois Halleen, Enrique Ferrada, Gonzalo A Díaz","doi":"10.1094/PDIS-11-24-2427-RE","DOIUrl":"https://doi.org/10.1094/PDIS-11-24-2427-RE","url":null,"abstract":"<p><p>Botryosphaeria canker and dieback is an important fungal disease caused by Botryosphaeriaceae spp. that affects the productivity of apple orchards in Chile and worldwide. In the field, studies on the management of this disease are focused on the protection by fungicides applied on pruning wounds. However, in Chile, information about the protection and efficacy of fungicides on apple trees against twig and branch pathogens is scarce. Therefore, in this study, we evaluated the efficacy of fungicides to control fungal trunk pathogens causing Botryosphaeria canker and dieback in apple trees using in vitro, glasshouse, and field trials. Isolates of Diplodia mutila, D. seriata, Neofusicoccum arbuti, and Lasiodiplodia theobromae obtained and characterized previously in Chile from apple trees with canker and dieback symptoms were used in this study. In vitro tests showed that benomyl, fluazinam, difenoconazole, and tebuconazole exhibited the lowest EC50 values with means of 0.08, 0.09, 0.12, and 0.18 μg/mL, respectively. This study demonstrates that infection caused by D. mutila, D. seriata, L. theobromae, and N. arbuti can be significantly reduced using single-sprayed protection of fungicides. The most effective in reducing infection on pruning wounds of apple trees by Botryosphaeriaceae were benomyl (66 to 76%), tebuconazole (47 to 68%), thiophanate-methyl (68 to 71%), boscalid + pyraclostrobin (47 to 63%), fluxapyroxad + pyraclostrobin (54 to 57%), and thiophanate-methyl + tetraconazole (63 to 74%). To our knowledge, this is the first study reporting the control of Botryosphaeriaceae causing canker and dieback in apple trees through the use of commercially available chemical fungicides, with different active ingredients and modes of action.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710867","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":"Systematic surveillance of Fusarium head blight in the southern region of the Republic of Korea.","authors":"Hosung Jeon, Jung-Wook Yang, Noh-Hyun Lee, Donghwan Shin, Donggyu Min, Nahyun Lee, Seul Gi Baek, Ju-Young Nah, Boeun Kim, Mi-Jeong Lee, In-Jeong Kang, Yul-Ho Kim, Kwang-Hyung Kim, Hokyoung Son, Theresa Lee","doi":"10.1094/PDIS-02-25-0282-SR","DOIUrl":"https://doi.org/10.1094/PDIS-02-25-0282-SR","url":null,"abstract":"<p><p>Fusarium head blight (FHB), caused by <i>Fusarium graminearum</i> species complex, is one of the most destructive plant diseases affecting wheat and barley globally. However, effective management methods remain elusive because of limited availability of resistant cultivars. Accordingly, systematic surveillance is one of the key strategies, allowing for prompt responses to emerging outbreaks and supporting the establishment of preventive guidelines for future occurrences. FHB severity in the southern region of the Republic of Korea in 2024 following an outbreak was systematically monitored. A total of 100 wheat (<i>n</i> = 43) and barley (<i>n</i> = 57) fields were assessed for FHB indices and mycotoxin concentrations. A geographical breakdown showed that several regions were heavily impacted by the FHB outbreak, with elevated disease severity exceeding 50%. Furthermore, spatiotemporal analysis of the FHB outbreak revealed relatively high disease severity in 2024, ranging from 3- to 6-fold compared to the previous years, likely influenced by climatic factors. A strong correlation of FHB severity and nivalenol concentrations was also observed, with concerning levels that underscore potential risk for future FHB outbreaks. These findings provide valuable insights into the epidemiology of FHB in the Republic of Korea and will help guide the development of more effective management strategies for FHB and its associated mycotoxins.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710877","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":"First Report of <i>Phytopythium vexans</i> Causing Root Rot on Norway Spruce (<i>Picea abies</i>) in Tennessee and the United States.","authors":"Pratima Subedi, Cansu Oksel, Prabha Liyanapathiranage, Terri Simmons, Fulya Baysal-Gurel","doi":"10.1094/PDIS-01-25-0157-PDN","DOIUrl":"https://doi.org/10.1094/PDIS-01-25-0157-PDN","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Norway spruce (&lt;i&gt;Picea abies&lt;/i&gt;), a pyramidal evergreen conifer, is widely grown as an ornamental tree and a popular choice for Christmas decorations. Three-year-old Norway spruce, grown under field conditions in a commercial nursery in Warren County, Tennessee, exhibited root rot and needle chlorosis in June 2024. The affected roots displayed dark brown to black lesions. Roots were evaluated for disease severity on a scale from 0% to 100%. Disease severity was 40% of the root area affected, while disease incidence was approximately 50% of 50 plants. Symptomatic root tissues were surface disinfected using 70% ethanol and washed twice with distilled water. Then, the symptomatic root tissues were plated on V8-PARPH (V8 juice agar amended with pimaricin, ampicillin, rifampicin, pentachloronitrobenzene, and hymexazol), and incubated at 25 ± 2°C with 8 h light/16 h dark cycle. Within three days of incubation, colonies with whitish radiate and chrysanthemum flower-like mycelial growth patterns were observed (Fig. 1a). Oogonia were smooth, ranging from filamentous to globose (16.25 ± 1.30 μm in diameter, &lt;i&gt;n&lt;/i&gt;=50) (Fig. 1b and c). Antheridia were cylindrical, elongate attached to the oogonia (Fig. 1c). Sporangia were subglobose (16.48 ± 1.74 × 22.05 ± 1.26 μm, &lt;i&gt;n&lt;/i&gt;=50) with papilla (Fig. 1d and e) that are characteristic of &lt;i&gt;Phytopythium vexans&lt;/i&gt; (Ghimire and Baysal-Gurel, 2023; Thao et al. 2020). Pathogen identity was confirmed by sequencing specific genetic markers amplified from genomic DNA extracted using DNeasy PowerLyzer Microbial Kit from 7-day-old pure cultures of the isolates (FBG8275 and FBG8276). The genetic markers for the ribosomal internal transcribed spacer (ITS), the large subunit (LSU), and mitochondrial cytochrome c oxidase subunits I (&lt;i&gt;CoxI&lt;/i&gt;) and II (&lt;i&gt;CoxII&lt;/i&gt;) were amplified and sequenced using the primer pairs ITS1/ITS4 (White et al., 1990), NL1/NL4 (Baten et al. 2014), OomCoxI-Levup/Fm85mod (Robideau et al., 2011), and Cox2-F/Cox2-R (Hudspeth et al., 2000), respectively. The ITS, LSU, &lt;i&gt;CoxI&lt;/i&gt;, and &lt;i&gt;CoxII&lt;/i&gt; sequences of isolates FBG8275 and FBG8276 (ITS: PQ723098 and PQ723099; LSU: PQ723103 and PQ723104; &lt;i&gt;CoxI&lt;/i&gt;: PQ728046 and PQ728047; &lt;i&gt;CoxII&lt;/i&gt;: PQ728048 and PQ728049) matched 754, 673, 612 and 563 base pairs, respectively with the corresponding &lt;i&gt;P. vexans&lt;/i&gt; sequences MK011115, OQ754108, GU133478, and AB468910, with 100% identity. The pathogenicity test was performed on 1-year-old Norway spruce plants grown in a 1-gal container (3.8 liter) to fulfill Koch's postulates. The plants were drench-inoculated (100 ml/plant) once with a mycelial slurry (two plates of 7-day-old culture/liter) of the isolates FBG8275 and FBG8276 (five plants per isolate). Five plants were drenched with pathogen-free agar slurry to serve as control. The study was conducted in a greenhouse condition (23°C to 25°C and 70% relative humidity). Two weeks after inoculation, dark brown to black lesions appeared on the roo","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710894","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":"Rapid Detection of <i>Xanthomonas fragariae</i> in Strawberry Using Species-Specific Primers Based on Comparative Genomics.","authors":"Sai Wang, Peihong Wang, Weixue Liao, Xiaohui Liu, Mingyan Ouyang, Sisi Lin, Rongpeng Lin, Zhengyin Xu, Gongyou Chen, Bo Zhu","doi":"10.1094/PDIS-11-24-2299-RE","DOIUrl":"https://doi.org/10.1094/PDIS-11-24-2299-RE","url":null,"abstract":"<p><p><i>Xanthomonas fragariae</i> poses a significant emerging threat to global strawberry production. The success of surveillance strategies and quarantine measures in controlling its international spread depends heavily on the availability of rapid and reliable in-planta detection tools. Polymerase chain reaction (PCR) is the preferred method for detecting systemic infections due to its high sensitivity, specificity, and ease of use. However, despite the availability of several PCR and real-time quantitative PCR methods, many face issues with analytical specificity. Given the ongoing global evolution of <i>X</i>. <i>fragariae</i> and the emergence of new variants, there is a critical need for adaptable detection methods. In this study, we designed a specific primer pair (XfOG4-F/XfOG4-R) through comparative genomic analysis of 660 genomes from the <i>Xanthomonas</i> genus. This primer set targets a region uniquely and consistently present in all eighty-one <i>X</i>. <i>fragariae</i> genomes available on NCBI. We validated the primer pair's specificity using colony PCR with both target <i>X</i>. <i>fragariae</i> strains and non-target <i>Xanthomonas</i> strains. Detection sensitivity was assessed using PCR and qPCR on isolated DNA and bacterial cell suspensions, both in vitro and in artificially inoculated strawberry leaves. The qPCR method demonstrated sensitivity 100 times higher than standard PCR. Additionally, the PCR test successfully detected the pathogen in extracts from naturally infected strawberry crown samples collected on farms. The new primer set showed improved analytical specificity over previously reported primers, offering a valuable tool for detecting <i>X</i>. <i>fragariae</i>-infected plants in future field surveys.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143710832","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":"First report of <i>Fusarium culmorum</i> and <i>Fusarium avenaceum</i> causing vascular necrosis in European hazelnut branches in Chile.","authors":"Ernesto Antonio Moya-Elizondo, Verónica Retamal, Juan G San Martín, Braulio E Ruiz, María José Lisperguer, Tommaso De Gregorio, Matteo Maspero","doi":"10.1094/PDIS-10-24-2253-PDN","DOIUrl":"https://doi.org/10.1094/PDIS-10-24-2253-PDN","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Hazelnut (&lt;i&gt;Corylus avellana&lt;/i&gt; L.) is the second most cultivated nut crop in Chile. Pathogens associated with fungal trunk diseases (FTD) pose a serious threat to this crop, because these fungi colonize the wood causing loss of productivity and eventually death of the plants (Martino et al., 2025). During Spring 2018 and 2020, FTD symptoms such as wood necrosis, vascular discoloration of branches, cankers, and wilted branches were detected in a survey conducted in 24 hazelnut orchards located between Maule and Araucanía regions, Chile (Moya-Elizondo et al., 2023). Wood pieces (3 mm x 5 mm) were removed from the edge of necrotic canker lesions, disinfected with 2% NaOCl, rinsed twice with sterile distilled water, and dried on sterile absorbent paper. Tissue pieces were placed on potato dextrose agar (PDA) supplemented with streptomycin sulphate (200 mg L⁻¹) and incubated at 25°C in darkness for five days. Different fungi were isolated from cankers, but based on morphological characteristics (pale pink or burgundy colonies), &lt;i&gt;Fusarium&lt;/i&gt; spp. were identified in 5.2% of the samples (27/520). Each colony was hyphal-tip purified in a new PDA plate. Macroconidia developed on sporodochia after 30 days of incubation at 25°C on carnation leaf agar. Two morphologically different isolates were analyzed. Colonies of isolate F066 were cottony, dark pink and light pink on the edges when grown on PDA. Macroconidia were hyaline, falcate with rounded apical cells, slightly curved, with 3 to 6 septa (30 to 53 x 5.2 to 6.2 µm). Isolate F094 presented slightly cottony colonies, light pink, and dark pink with pale yellow hues in the central area with macroconidia of similar morphological shape but measuring 36 to 55 x 2.8 to 4.2 µm. In both isolates, chlamydospores and microconidia were absent. The ITS, RPB2, and TEF-1α genomic regions were amplified with primers ITS1/ITS4, 7cf/11ar, and EF1/EF2, respectively (Sandoval-Denis et al., 2018). The ITS (MT640271, PP928999), RPB2 (MT997139, PP934182), and TEF-1α (MT661593, PP934183) sequences were deposited in GenBank, showing 100% similarity with reference sequences of &lt;i&gt;Fusarium culmorum&lt;/i&gt; (Wm.G.Sm.) Sacc. and &lt;i&gt;Fusarium avenaceum&lt;/i&gt; (Corda) Sacc. for ITS: (MK729631, MT463390), RPB2 (GQ915490, MK185027), and TEF-1α (MN044434, KP400709), respectively. To fulfil Koch's postulates, pathogenicity was evaluated in 8-year-old hazelnut plants cv. Tonda di Giffoni in a commercial orchard. A hole of 6.5 mm in diameter was made in healthy branches using an electric drill and an actively growing mycelial disc (5 mm) was placed into five branches per isolate, ensuring contact of the mycelium with the wood. The wounds were sealed with plastic film to prevent contamination and desiccation. Additionally, PDA discs were inoculated as a control. After seven months, branches were cut longitudinally to verify wood necrosis. Inoculation with isolates F066 and F094 resulted in necrotic lesions ranging between 50-125 mm and 3","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676987","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":"Etiological agents of Fusarium crown rot in Illinois wheat.","authors":"Imane Laraba, Martha M Vaughan, Susan P McCormick, Mark Busman, Christina Cowger, Peter Oppenheimer, Joseph Opoku, Briana Kathleen Whitaker","doi":"10.1094/PDIS-09-24-2034-RE","DOIUrl":"https://doi.org/10.1094/PDIS-09-24-2034-RE","url":null,"abstract":"<p><p>The world is experiencing major changes in both climate and agronomic practices, which are intensifying the need to monitor plant diseases as they expand into new growing regions. Fusarium crown or foot rot is one disease of wheat and other cereals that has previously been the subject of economic concern and research primarily in arid to semi-arid regions of the world. Many of the etiological agents involved in Fusarium crown rot (FCR) are cross-pathogenic in head tissues, causing the disease Fusarium head blight and increasing the risk for mycotoxin contamination of foods. During a survey of Fusarium head blight in the midwestern US state of Illinois in 2022, four soft red winter wheat fields displayed a high incidence of severe crown rot symptoms. The etiological agents of the observed symptoms were identified by translation elongation factor 1α sequencing, which revealed Fusarium graminearum, F. parabolicum, and F. acuminatum as the primary agents of FCR in Illinois wheat. The dominant Fusarium species varied across fields, with recovered isolates spanning five Fusarium species complexes, and a high diversity of likely secondary colonizers was also noted across fields. Lastly, no mycotoxins were detected in the screened wheat heads. Our results highlight the impact of local conditions in driving FCR and pathogen dynamics, even with relatively limited distances between fields. The identification of FCR agents in Illinois will serve as a resource for crop managers and breeders targeting effective control strategies in a changing agroecosystem.</p>","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676948","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":"First Report of Leaf Blight on <i>Lithocarpus litseifolius</i> Caused by <i>Diaporthe amygdali</i> in China.","authors":"Yuling Wang, Jing Liu, Meng Li, Changjiang Liu, Shuai Li, Zixuan Qiu, Wuping Yan","doi":"10.1094/PDIS-11-24-2287-PDN","DOIUrl":"https://doi.org/10.1094/PDIS-11-24-2287-PDN","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Lithocarpus litseifolius is a third-generation new tea source that integrates \"tea, sugar, and medicine\" (Wang et al., 2021). In July 2023, a leaf blight on L. litseifolius was observed in the L. litseifolius plantation (0.33 ha) at Mount Dajue, Fuzhou City, Jiangxi Province, China (27.696119°N, 117.172554°E). The disease incidence was estimated to be above 40%. The symptoms on leaves showed brown necrotic lesions at the tips and margin of leaves, and localized areas on leaf blades. As the disease developed, the lesions enlarged and the leaves incurved with time and, in severe cases, the whole leaves became light brown, necrotic, desiccated, papery, dead, and eventually defoliated. We collected 10 leaves from the diseased area for pathogen isolation. The leaf tissue near the lesion was cut into 5 × 5 mm slices, disinfected with 75 % ethanol for 30 s, soaked in 2.5 % sodium hypochlorite solution for 3 min, and washed with sterile distilled water 4 times. The sterilized leaves were placed on potato dextrose agar (PDA) plates and incubated in darkness at 28°C for 3 days to isolate symptom-related pathogens. After 3 days of incubation, hyphal tips from the edge of the growing colony were transferred to fresh PDA plates for further purification. Finally, 10 colonies with similar morphology were isolated from 10 symptomatic tissues. Fungal colonies initially appear white, turning pale gray from the center with dense and felted mycelium with concentric zonation. The alpha conidia were on average 2.56× 5.84 μm ( 2.00 to 3.80 × 3.96 to 7.89 μm) in size and were aseptate, hyaline, smooth, and ellipsoidal (n = 30). Based on these morphological characteristics, the fungi were determined to be Diaporthe species (Gomes et al. 2013). The internal transcribed spacer region (ITS), a partial sequence of β-tubulin gene (Tub2) and translation elongation factor 1-α gene (TEF1) of one representative isolate 2BDJS1 were amplified and sequenced using primers ITS1/ITS4 (White et al., 1990), Bt2a/Bt2b (Glass and Donaldson, 1995), and EF1-728F/EF1-986R (Carbone and Kohn, 1999), respectively. The nucleotide sequences obtained from isolate 2BDJS1 were deposited in GenBank under accession numbers PQ185599 (ITS), PQ358310 (TEF1), and PQ358311 (Tub2). BLASTn analysis revealed that the ITS, TEF1, and Tub2 sequences of isolate 2BDJS1 exhibited 97.98%, 95.16%, and 99.79% similarity, respectively, to those of the D. amygdali isolate DJY-HW-1 (GenBank accession numbers MK511798 for ITS, MK570512 for TEF1, and MK570513 for Tub2). A Maximum-Likelihood (ML) phylogenetic tree was constructed using the concatenated ITS-TEF1-Tub2 multigene sequences in MEGA7. The results indicated that isolate 2BDJS1 clustered independently with two reference strains of D. amygdali, with a bootstrap support value of 99%. Combining these molecular data with morphological characteristics, including colony morphology and alpha conidia morphology, we confidently identified isolate 2BDJS1 as D. amygdali.","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143677002","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":"First report of <i>Colletotrichum fructicola</i> causing Anthracnose on the leaf of flowering cherry (<i>Prunus serrulata</i> 'Sekiyama') in China.","authors":"Yufu Peng, Guohang Wang, Xueling Ouyang, Huohui Peng, Xiaoqun Xie, Yong Peng, Shuai Hu, Hualing Chen, Xuezhen Yang","doi":"10.1094/PDIS-11-24-2302-PDN","DOIUrl":"https://doi.org/10.1094/PDIS-11-24-2302-PDN","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Flowering cherry (&lt;i&gt;Prunus serrulata&lt;/i&gt;) is a notable garden tree that blooms in early spring. In June 2023, an anthracnose disease was identified on 60% of &lt;i&gt;P. serrulata&lt;/i&gt; 'Sekiyama' plants in the Fenghuanggou Scenic Area (0.2 ha.) in Nanchang City, Jiangxi Province (28.37° N, 116.01° E). At early disease stages, brown, small spots (0.5 to 1 mm) appeared on the upper surface of leaves. Subsequently, a chlorotic halo developed around each lesion. Then necrotic lesions were enlarged, the leaves were perforated. Ten symptomatic leaves were collected from 5 trees, rinsed under running water for 3 min, sectioned into 5×5 mm pieces, disinfected in 75% ethanol for 30 sec and rinsed three times with sterile water. Tissue pieces were placed on potato dextrose agar (PDA) and incubated at 27 °C for three days. Among the 15 isolates, 5 isolates with similar morphology were obtained from the 10 infected tissue pieces. Colonies were off-white with cotton-like hyphae, with the reverse of the culture became brownish. Conidia were hyaline, smooth-walled, cylindrical, aseptate, and had wide rounded ends and were measured 0.91 to 1.41 μm × 2.11 to 3.18 μm (n=28). To identify these isolates, ITS1/ITS4 (Gardes and Bruns, 1993) primers were first used to amplify the &lt;i&gt;ITS&lt;/i&gt; sequence, and it was found that the five isolates had 100% homology to the genus &lt;i&gt;Colletotrichum&lt;/i&gt; (Tang et al., 2022). One isolate (ZJ1-1) was selected for subsequent verification, and partial chitin synthase (&lt;i&gt;CHS&lt;/i&gt;), calmodulin (&lt;i&gt;CAL&lt;/i&gt;) and glyceraldehyde-3-phosphate dehydrogenase (&lt;i&gt;GAPDH&lt;/i&gt;) genes were amplified with the primers CHS-79F/CHS-345R (Carbone and Kohn, 1999), CL1C/CL2C (Weir et al., 2012) and GDF/GDR (Templeton et al., 1992), respectively. Sequences were deposited in GenBank as accession numbers PP481926 (CHS), PP481927 (CAL), PP481925 (GAPDH), and PP077091 (ITS). Blast analysis demonstrated that the sequences were 99% to 100% identical with those of &lt;i&gt;Colletotrichum fructicola&lt;/i&gt; isolate ICMP18646 (JX009874, JX009674, JX010032, JX010173). A phylogenetic tree was produced using &lt;i&gt;CHS-CAL-GAPDH-ITS&lt;/i&gt; concatenated sequences in MEGA 11.0 and found that ZJ1-1 was assigned to the &lt;i&gt;C. fructicola&lt;/i&gt; clade with 95% bootstrap support. According to its morphological characteristics and molecular biology, the strain was identified as &lt;i&gt;C. fructicola&lt;/i&gt; ( Kang et al., 2023). The fungus ZJ1-1 was inoculated onto healthy 3-year-old &lt;i&gt;P. serrulata&lt;/i&gt; 'Sekiyama' trees. 3 trees were wounded and inoculated with 10 μL spore suspension (1.0×106 conidia/mL) of ZJ1-1, and other 3 trees were inoculated with sterile ddH2O to act as the control. The inoculated plants were incubated in a greenhouse with 27 ℃ and 95% RH. Each plant was inoculated on three leaves, with three replicates. Symptoms of anthracnose appeared on the third day following inoculation, but no symptoms appeared on the trees maintained as controls. &lt;i&gt;C. fructicola&lt;/i&gt; was re-isolated (named 003) ","PeriodicalId":20063,"journal":{"name":"Plant disease","volume":" ","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676957","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}