Elaborative Report of Allium sativum Clove Brown Rot Caused by Fusarium solani in China

HomePlant DiseaseVol. 108, No. 4Elaborative Report of Allium sativum Clove Brown Rot Caused by Fusarium solani in China PreviousNext DISEASE NOTE OPENOpen Access licenseElaborative Report of Allium sativum Clove Brown Rot Caused by Fusarium solani in ChinaMingzhao Zhu, Huanhuan Xu, and Yongqin WangMingzhao Zhuhttps://orcid.org/0000-0002-6703-4171State Key Laboratory of Vegetable Biobreeding, National Engineering Research Center for Vegetables, Beijing Key Laboratory of Vegetable Germplasms Improvement, Key Laboratory of Biology and Genetics Improvement of Horticultural Crops (North China), Beijing Vegetable Research Center, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China, Huanhuan XuState Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China, and Yongqin Wang†Corresponding author: Y. Q. Wang; E-mail Address: [email protected]State Key Laboratory of Vegetable Biobreeding, National Engineering Research Center for Vegetables, Beijing Key Laboratory of Vegetable Germplasms Improvement, Key Laboratory of Biology and Genetics Improvement of Horticultural Crops (North China), Beijing Vegetable Research Center, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, ChinaAffiliationsAuthors and Affiliations Mingzhao Zhu1 Huanhuan Xu2 Yongqin Wang1 † 1State Key Laboratory of Vegetable Biobreeding, National Engineering Research Center for Vegetables, Beijing Key Laboratory of Vegetable Germplasms Improvement, Key Laboratory of Biology and Genetics Improvement of Horticultural Crops (North China), Beijing Vegetable Research Center, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China 2State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China Published Online:8 Apr 2024https://doi.org/10.1094/PDIS-01-24-0232-PDNAboutSectionsView articlePDFSupplemental ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat View articleIn September 2023, brown rot disease was observed on cloves of garlic (Allium sativum) variety Zipi-1 (purple skin) collected from Jinxiang County, China, during scientific research at the Beijing Academy of Agricultural and Forestry Sciences after being planted in nutrient soil for approximately 2 weeks in a growth chamber maintained at 22°C, 60% relative humidity, and 16 h of light. Out of 90 garlic cloves investigated, 18 showed signs of decay, characterized by a brown color and rot, with the surface covered by blue and white mold layers. Six symptomatic cloves were collected for isolating the pathogen using the method described in a previous study (Wu et al. 2021). After 2 days of incubation, individual spores were harvested from the fungal colonies and recultured. Single-spore cultures growing on potato dextrose agar were white and flocculent on the upper side and yellowish brown on the reverse side. After 5 days of cultivation, the colonies had a diameter of approximately 5.8 cm, and microscopic examination revealed that the mycelium had a diameter of about 9 to 13 μm. The isolate As1 produced three types of spores: oval-shaped chlamydospores with a diameter of approximately 6 μm, and spindle-shaped microconidia and sickle-shaped macroconidia measuring approximately 6 to 7 × 20 to 30 μm and 8 × 50 μm, respectively. The mycelial characteristics and reproductive structures of the isolates were consistent with the morphological description of Fusarium solani (Xie et al. 2022). To confirm the identification, translation elongation factor (TEF1), RNA polymerase II largest subunit (RPB1), and second-largest subunit (RPB2) regions of the genome were amplified from three separate isolates (As1, As2, and As3) using EF1/EF2, RPB1-Fa/G2R, RPB2-5F2/7cR, and RPB2-7cF/11aR primer pairs (O'Donnell et al. 2022). The results indicated that the sequences of the three isolates were completely identical. Furthermore, the BLASTn comparison results of the TEF1 (OR916018, 710 bp, 100%), RPB1 (OR916019, 1,797 bp, 99.8%), and RPB2 (OR916020, 1,874 bp, 100%) sequences in the FUSARIUM-ID version 3.0 database revealed that As1 was F. solani species complex 5 (O'Donnell et al. 2022). To confirm the pathogenicity of As1, the surface of healthy garlic cloves (n = 30) was inoculated with the As1 conidial suspension (106 microconidia/ml), while a control group (n = 30) was inoculated with sterile water. All inoculated cloves were placed in an artificial climate chamber under the same conditions described above. After 10 days, all inoculated cloves exhibited rot symptoms consistent with those of the initially infected cloves identified in September 2023, whereas the control plant cloves remained asymptomatic. Based on morphological and molecular characteristics (TEF1, RPB1, and RPB2), the reisolated pathogen from diseased plants was identical to the As1 isolate used for inoculation, and the disease assays were repeated two times. Fusarium spp. have been reported as the causal agent of garlic rot disease in several countries such as Mexico, America, and Russia (Gálvez and Palmero 2022). Tai (1979) previously published a report on the presence of F. solani in garlic; however, the content in the book is rather basic, lacking detailed information on the isolation, identification, and the potential for causing pre- or postharvest garlic diseases. Our research can be considered a supplement and improvement to the study by Tai (1979) and lays the groundwork for future studies on management strategies to combat plant diseases caused by F. solani.The author(s) declare no conflict of interest.References:Gálvez, L., and Palmero, D. 2022. Horticulturae 8:628. https://doi.org/10.3390/horticulturae8070628 Crossref, ISI, Google ScholarO'Donnell, K., et al. 2022. Plant Dis. 106:1597. https://doi.org/10.1094/PDIS-09-21-2035-SRLink, ISI, Google ScholarTai, F. L. 1979. Sylloge Fungorum Sinicorum. Sci. Press, Acad. Sin., Beijing, China. Google ScholarWu, D., et al. 2021. Plant Dis. 105:1562. https://doi.org/10.1094/PDIS-09-20-2003-PDNLink, ISI, Google ScholarXie, S.-Y., et al. 2022. Microbiol. Spectr. 10:e00683‐22. https://doi.org/10.1128/spectrum.00683-22Crossref, ISI, Google ScholarFunding: This work was supported by the National Natural Science Foundation of China (grant no. 31972409) and Science Innovation of the Beijing Academy of Agriculture and Forestry Sciences (grant no. KJCX20230123).The author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 108, No. 4 April 2024SubscribeISSN:0191-2917e-ISSN:1943-7692 Download Cover Image Metrics Article History Issue Date: 29 Apr 2024Published: 8 Apr 2024First Look: 1 Mar 2024Accepted: 28 Feb 2024 Page: 1116 Information© 2024 The American Phytopathological SocietyFundingNational Natural Science Foundation of ChinaGrant/Award Number: 31972409Beijing Academy of Agriculture and Forestry SciencesGrant/Award Number: KJCX20230123Keywordsfungipathogen detectionvegetablesThe author(s) declare no conflict of interest.PDF download