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Poster: Diseases of Plants: Disease Detection & Diagnosis


Identifying and characterizing fungal pathogens causing seedling diseases of soybean through a multi-state survey
A. WARNER (1), J. Bond (2), A. Fakhoury (2) (1) Southern Illinois University Carbondale, U.S.A.; (2) Southern Illinois University Carbondale, U.S.A.

Seedling diseases are common and very detrimental to soybean, Glycine max. They are caused by a variety of plant pathogens including fungi, bacteria, and oomycetes. The central goal of this project was to identify fungal pathogens causing seedling diseases of soybean in various soybean producing states. Two approaches were used for genus and species determination, including morphological features using microscopy and the sequencing of specific genetic loci. For sequencing, up to three different barcodes were targeted, the internal transcribed spacer (ITS), the elongation factor EF-1α, and the intergenic spacer (IGS). The data produced from this project included the identification of approximately 150 fungal isolates per state from eight different states: Arkansas, Indiana, Illinois, Iowa, Nebraska, Michigan, Minnesota, and Kansas. Isolates were collected in 2012 and 2013 to help determine the predominant causal agents of seedling diseases of soybean in those surveyed locations. A variety of genera were isolated from the fields surveyed, with Fusarium species constituting approximately 74% of the isolates. Data analyses also involved determining associations and correlations between different factors, such as cultural practices, soil physical and chemical properties, irrigation practices, cropping history, and the frequency of the incidence of the species in the surveyed locations.