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 belongs to the family Nectriaceae and groups most closely with Cylindrocarpon olidum. It was isolated from the cyst of a soybean cyst nematode. Taxonomic studies of fungi with Cylindrocarpon-like anamorphs suggest this isolate belongs to the teleomorphic genus Thelonectria (Salgado-Salazar et al., 2016, Rossman et al., 2013). Fungi identified as C. olidum have been previously detected in relatively high abundance in studies of mycota inhabiting both the cysts of soybean cyst nematode (Chen and Chen, 2002) and the egg masses of the root knot nematode (Kok et al., 2001). Chemical analysis of C. olidum has identified the metabolie Cannabiorcichromenic acid, which shows both antifungal activity and is toxic to nematodes(Quaghebeur et al., 1994).
Researchers who wish to publish analyses using data from unpublished CSP genomes are respectfully required to contact the PI (Dr. Kathryn Bushley) and JGI to avoid potential conflicts on data use and coordinate other publications with the CSP master paper(s).
References:
- Chen, F. J. & Chen, S. Y. 2002. Mycofloras in cysts, females, and eggs of the soybean cyst nematode in Minnesota. Applied Soil Ecology, 19, 35-50.
- Kok, C. J., Papert, A. & Hok-A-Hin, C. H. 2001. Microflora of Meloidogyne egg masses:: species composition, population density and effect on the biocontrol agent Verticillium chlamydosporium (Goddard). Nematology, 3, 729-734.
- Quaghebeur, K., Coosemans, J., Toppet, S. & Compernolle, F. 1994. Cannabiorcichromenic and 8-chlorocannabiorcichromenic acid as fungal antagonists from Cylindrocarpon olidum. Phytochemistry, 37, 159-161.
- Rossman, A. Y., Seifert, K. A., Samuels, G. J., Minnis, A. M., Schroers, H. J., Lombard, L., Crous, P. W., Poldmaa, K., Cannon, P. F., Summerbell, R. C., Geiser, D. M., Zhuang, W. Y., Hirooka, Y., Herrera, C., Salgado-Salazar, C. & Chaverri, P. 2013. Genera in Bionectriaceae, Hypocreaceae, and Nectriaceae (Hypocreales) proposed for acceptance or rejection. Ima Fungus, 4, 41-51.
- Salgado-Salazar, C., Rossman, A. Y. & Chaverri, P. 2016. The genus Thelonectria (Nectriaceae, Hypocreales, Ascomycota) and closely related species with cylindrocarpon-like asexual states. Fungal Diversity, 80, 411-455.
