Submitted to: Mid Atlantic Plant and Molecular Biology Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 30, 2001
Publication Date: N/A
The soybean cyst nematode (SCN) is the major pest of soybean causing an estimated $1.5 billion in damage throughout the US each year, more than all other soybean pests combined. The defense response of soybean to SCN is a multigenic trait and varies depending upon the genotypes of soybean and SCN. The expression of approximately 1,500 soybean genes was monitored using microarrays to identify genes involved in the response of soybean to SCN. RNA was harvested from roots of soybean cv. Peking resistant to SCN race 3 and cv. Kent susceptible to SCN race 3, either two days after infection by SCN race 3 or not infected. Three independent biological samples were harvested and analyzed for each experiment. 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. The number of genes that were at least 2-fold 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 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.