D. N. Colombo, A. Figueruelo, N. B. Paniego, R. M. Comerio, A. Corró Molas
{"title":"Phomopsis Head Rot caused by Diaporthe helianthi: A New Disease on Sunflower in Argentina","authors":"D. N. Colombo, A. Figueruelo, N. B. Paniego, R. M. Comerio, A. Corró Molas","doi":"10.1111/jph.13416","DOIUrl":null,"url":null,"abstract":"<div>\n \n <p>During a survey conducted in the 2021, 2022 and 2023 seasons, sunflower heads showing symptoms of dry rot were collected from 80 fields in the semi-arid Pampa region of Argentina. A total of 72% of the fields examined in 2021, 71% in 2022 and 63% in 2023 showed the presence of the disease. The highest incidence was recorded as 70% in 2021. Phomopsis head rot began as dry, brown spots on the back of the head, progressing to necrosis and twisting of adjacent leaves. Infected head tissue samples were surface sterilised, cultured on potato dextrose agar (PDA) and incubated at 25°C for 14 days. <i>Diaporthe helianthi</i> was identified based on cultural and morphological characteristics as well as molecular data. A phylogenetic analysis was performed. Internal transcribed spacer (ITS), translation elongation factor 1-α (<i>ef1-α</i>) and β-tubulin sequences were deposited in GenBank, showing the identity with the ex-type <i>D. helianthi</i> strain CBS 592.81. Pathogenicity experiments confirmed the presence of similar disease symptoms in inoculated sunflower heads, and <i>D. helianthi</i> was consistently reisolated from these organs. Our Koch's postulates testing results on heads constitute the first confirmed report that <i>D. helianthi</i> is the cause of Phomopsis head rot on sunflower in Argentina.</p>\n </div>","PeriodicalId":16843,"journal":{"name":"Journal of Phytopathology","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Phytopathology","FirstCategoryId":"97","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/jph.13416","RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
During a survey conducted in the 2021, 2022 and 2023 seasons, sunflower heads showing symptoms of dry rot were collected from 80 fields in the semi-arid Pampa region of Argentina. A total of 72% of the fields examined in 2021, 71% in 2022 and 63% in 2023 showed the presence of the disease. The highest incidence was recorded as 70% in 2021. Phomopsis head rot began as dry, brown spots on the back of the head, progressing to necrosis and twisting of adjacent leaves. Infected head tissue samples were surface sterilised, cultured on potato dextrose agar (PDA) and incubated at 25°C for 14 days. Diaporthe helianthi was identified based on cultural and morphological characteristics as well as molecular data. A phylogenetic analysis was performed. Internal transcribed spacer (ITS), translation elongation factor 1-α (ef1-α) and β-tubulin sequences were deposited in GenBank, showing the identity with the ex-type D. helianthi strain CBS 592.81. Pathogenicity experiments confirmed the presence of similar disease symptoms in inoculated sunflower heads, and D. helianthi was consistently reisolated from these organs. Our Koch's postulates testing results on heads constitute the first confirmed report that D. helianthi is the cause of Phomopsis head rot on sunflower in Argentina.
期刊介绍:
Journal of Phytopathology publishes original and review articles on all scientific aspects of applied phytopathology in agricultural and horticultural crops. Preference is given to contributions improving our understanding of the biotic and abiotic determinants of plant diseases, including epidemics and damage potential, as a basis for innovative disease management, modelling and forecasting. This includes practical aspects and the development of methods for disease diagnosis as well as infection bioassays.
Studies at the population, organism, physiological, biochemical and molecular genetic level are welcome. The journal scope comprises the pathology and epidemiology of plant diseases caused by microbial pathogens, viruses and nematodes.
Accepted papers should advance our conceptual knowledge of plant diseases, rather than presenting descriptive or screening data unrelated to phytopathological mechanisms or functions. Results from unrepeated experimental conditions or data with no or inappropriate statistical processing will not be considered. Authors are encouraged to look at past issues to ensure adherence to the standards of the journal.