Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: May 25, 2001
Publication Date: N/A
Soybean cyst nematode (SCN) is a major pest of soybean causing losses in millions of dollars. The presence of SCN elicits a variety of defense responses in the soybean plant. The resistance of soybean to SCN is a multigenic trait that varies depending upon the genotypes of soybean and SCN. Elucidation of the gene expression profile of defined soybean genotypes will be useful for developing soybean plants with improved resistance to present and evolving SCN races. Furthermore, it will help in understanding the molecular mechanisms underlying resistance in this, and other plant-pathogen interactions. In order to provide a genome-wide analysis of the soybean genes that are expressed specifically in the roots of a resistant and a susceptible cultivar in response to a specific SCN isolate, microarray technology was used. Microarrays were produced that display PCR amplified cDNA inserts from approximately 1500 root-specific genes. These genes are derived from cDNA libraries made from root tissue of resistant soybean cultivars infected or not infected by SCN. The arrays were hybridized with probes derived from root mRNA of Peking (resistant) or Kent (susceptible) cultivars two days after infection with SCN. The number of genes that were induced in the presence of SCN was higher in the resistant cultivar as compared to the susceptible cultivar. Among the genes induced specifically in the resistant soybean variety are defense-related genes, potential regulatory factors such as kinases, phosphatases and transcription factors, and a number of genes encoding proteins of unknown function. These results provide some insights into the mechanisms used by soybean to respond to SCN attack.