Within the framework of JGI "Community Sequencing Project: Defensive Mutualism of Fungal Root Endophytes of Soybean" CSP project, we are investigating the potential role of fungal endophytes isolated from soybean roots in protecting the plant from two devastating root plant pathogens: 1) the root rot fungus causing Soybean Sudden Death Syndrome (Fusarium virguliforme) and 2) the soybean cyst nematode (Heterodera glycines). These fungi were screened for either anti-fungal or anti-nematode activity in-vitro and genome, transcriptome, and metabolome sequencing will address possible mechanisms of antagonism against these pathogens.
This isolate falls within the family Mycosphaerellaceae (Capnodiales, Dothideomycetes), grouping most closely to sequenced strains of the genus Ramularia. Mycosphaerellaceae includes many plant pathogens of diverse plant hosts, including those in genus Mycosphaerella and one of its anamorphic taxa Ramularia [1], causing disease symptoms (leaf spot, leaf blotch, shoot blight and stem cankers) on both monocot and dicot hosts [2-5]. This isolate was cultured from a soybean showing no signs of disease. In vitro competition assays showed that it inhibited growth of F. virguliforme.
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