Author
NJAMBERE, EVANS - Washington State University | |
Vandemark, George | |
Chen, Weidong |
Submitted to: Genome
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/15/2009 Publication Date: 6/1/2010 Citation: Njambere, E., Vandemark, G.J., Chen, W. 2010. Development and characterization of microsatellite markers of the fungal plant pathogen Sclerotinia trifoliorum. Genome. 53:494-200. Interpretive Summary: Sclerotinia trifoliorum was recently found to infect chickpea (Cicer arientinum) in North America. Very little is known about the biology and genetic structure of the pathogen. There are no molecular markers available that can be applied to S. trifoliorum. This study reports the development, characterization, transferability and utility of thirty-three microsatellite loci developed from a microsatellite-enriched library of S. trifoliorum. Many of the microsatellite markers are also applicable to related species of Sclerotinia. These markers are therefore useful for population structure assessment and ecological studies in S. trifoliorum and potentially in other Sclerotinia species. Knowledge of the genetic diversity within and between populations of the fungus will assist in the development of fungicides that can be used to reduce diseases caused by this pathogen in chickpea and other species. Technical Abstract: Sclerotinia trifoliorum was recently found to infect chickpea (Cicer arientinum) in North America. Attempts to study the population biology of this pathogen using previously developed microsatellite markers for closely related species S. sclerotiorum and S. sub-arctica resulted in little or no amplification or low levels of polymorphism. This study reports the development, characterization, transferability and utility of thirty-three microsatellite loci developed from a microsatellite-enriched library of S. trifoliorum. An average of 6.5 alleles per locus (range 3-12) and a mean expected heterozygosity of 0.63 (range 0.26-0.9) was found using a panel of 42 isolates of S. trifoliorum. Based on the genome sequences of S. sclerotiorum, the microsatellite loci are dispersed throughout the genome. However, 50% (265 of the 528) of pairwise comparisons of the 33 microsatellite loci had significant linkage disequilibrium. This was not unexpected since S. trifoliorum is a partially outcrossing fungus. Thirty of the 33 loci were successfully applied to congeneric S. sclerotiorum and 28 loci were polymorphic, ten loci in S. minor and one loci in S. homoeocarpa. These markers are therefore useful for population structure assessment, QTL mapping and ecological analyses in S. trifoliorum and potentially in other Sclerotinia species.[National Sclerotinia Initiative] |