Submitted to: APS Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: August 13, 2003
Publication Date: December 20, 2002
Citation: Clough, S.J., Vuong, T.D., Hartman, G.L. 2002. Genomic Analyis of white mold resistence in soybean. APS Annual Meeting. v. 93. p. S17. Technical Abstract: Sclerotinia sclerotiorum is an important pathogen of soybean producing the disease known as either Sclerotinia Stem Rot or White Mold. Partial resistance to this pathogen has been reported; however, understanding of the molecular basis of resistance is limited. The recently developed cDNA microarray technology provides a promising tool to aid our search for genes involved in resistance to this disease. The power of this tool lies in its ability to measure the expression of tens of thousands of genes simultaneously at any specific time point and to compare that directly to a control sample. We will use cDNA microarrays, representing at least 18,000 different genes from soybeans, to detail the genetic responses of soybeans to this pathogen and to search for specific genes governing soybean resistance. The susceptible cultivar Williams 82 and the resistant plant introduction PI194639 were inoculated by applying an agar plug containing a fresh culture of S. sclerotinia to a freshly cut stem. The top 1.5 inches of inoculated or mock inoculate stem was collected at 0, 3, 18, and 48 hours post inoculation and immediately frozen in liquid nitrogen and stored at minus 80 degrees C. Total RNA was isolated from these tissues by Trizol extraction and is being labeled with fluorescent dUTP to determine gene expression profiles using the soybean microarrays. Genes that show strong correlation with resistance will be converted into molecular markers to determine if they are associated with known QTLs.