Location: Crop Production and Pest Control ResearchTitle: Identification of Fusarium fujikuroi as a new root rot pathogen of soybean in Indiana
|DETRANALTES, CHRISTOPHER - Purdue University|
|JONES, CHRISTOPHER - Purdue University|
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2021
Publication Date: 8/2/2021
Citation: Detranaltes, C., Jones, C.J., Cai, G. 2021. Identification of Fusarium fujikuroi as a new root rot pathogen of soybean in Indiana. American Phytopathological Society Abstracts. Plant Health 2021. 2-6 Aug 2021 (virtual).
Technical Abstract: Identifying new pathogens in local environments is an integral part of disease management. A screening for typical and emergent seedling pathogens of soybean (Glycine max L.) grown at Purdue’s ACRE farm was conducted in summer of 2020. Two isolates of Fusarium fujikuroi (Sawada) Wollenw. were recovered from seedlings showing dry brown root discoloration and necrotic cotyledons, symptoms typical of seedling infection by Fusarium spp. Cultures were obtained from surface sterilized root tissue on water agar and semi-selective media and purified by single-spore isolation. Morphological examinations of the cultures and spores were consistent with species descriptions of F. fujikuroi. The ITS, mtSSU, and tef1-a molecular barcodes were sequenced and matched 100% to accessions of F. fujikuroi deposited in GenBank. To complete Koch’s postulates, sterilized sand-cornmeal media was inoculated either with plugs of a 7-day old isolate on CMA or sterile CMA plug controls. Soybean seeds (cv. Williams) were planted directly on the media, covered, and grown in a greenhouse for 14 days. All seedlings grown on infested media showed symptoms of root rot consistent with field symptoms while controls were healthy. F. fujikuroi was recovered from infected plants but not controls and identified as above. Some infected seedlings showed stem elongation as a symptom of infection compared to their matched controls, a first for this host. This is the first report of Fusarium fujikuroi infecting soybean in the state of Indiana, warranting assessments of disease risk in this newly reported geographic distribution.