ARS | Publication request: Development and characterization of microsatellite markers in Sclerotinia trifoliorum

Submitted to: Proceedings of the International Sclerotinia Workshop
Publication Type: Abstract Only
Publication Acceptance Date: May 15, 2009
Publication Date: December 15, 2009
Citation: Njambere, E., Vandemark, G.J., Chen, W. 2009. Development and characterization of microsatellite markers in Sclerotinia trifoliorum. Proceedings of the International Sclerotinia Workshop.

Technical Abstract: Sclerotinia trifoliorum is an important pathogen of leguminous forage crops and a few vegetable crops. Recently it has been also reported to cause stem and crown rot of chickpea in California. Little is known about the population diversity of this pathogen. Our attempts to use previously developed microsatellites markers for Sclerotinia sclerotiorum and S. subarctica resulted in either no amplification or low levels of polymorphism in S. trifoliorum. This study was initiated to develop microsatellite markers specific for S. trifoliorum. A microsatellite-enriched library was constructed from the S. trifoliorum genome using the SuperSNX linker technique (Glenn and Schable, 2005, Methods in Enzymology 395:202-222). Sixty clones from the library were arbitrarily selected and sequenced. Fifty-six primer pairs flanking microsatellite repeats were designed and tested on eight isolates of S. trifoliorum and four isolates of S. sclerotiorum. Thirty-three of the 56 microsatellite loci were found to be polymorphic. For the eight isolates of S. trifoliorum, the polymorphic loci showed an average of 4.4 alleles per locus (ranged 3 to 8) and an average expected heterozygosity of 0.63 (range 0.59 to 0.76). All the markers could cross amplify S. sclerotiorum, and many of them were polymorphic. These markers will be useful for further investigations on population structure and ecological analysis in S. trifoliorum and potentially in other Sclerotinia species.