|Van De Mortel, Martijn|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2007
Publication Date: 7/1/2007
Citation: Van De Mortel, M., Schneider, K., Bancroft, T., Nettleton, D., Frederick, R.D., Baum, T.J., Whitham, S.A. 2007. Gene expression in a soybean cultivar containing the Rpp3 gene for resistance to Phakopsora pachyrhizi. Phytopathology. 97(7):S117
Technical Abstract: Phakopsora pachyrhizi, the causal agent of soybean rust (SBR), is now established in all major soybean-producing countries. Since none of the four known rust resistance genes, Rpp1 through Rpp4, appear to be durable in the field, information about the molecular basis of P. pachyrhizi-soybean interactions is needed to assist future efforts to develop effective, broad-spectrum resistance. Toward this end, the abundance of soybean mRNA transcripts was measured over a twelve-day time course using the Affymetrix Soybean Genome Array in incompatible and compatible SBR-interactions. A soybean line containing the Rpp3 resistance gene, PI462312 was inoculated with the P. pachyrhizi isolates Hawaii 94-1 and Taiwan 80-2, which result in incompatible and compatible reactions, respectively. Soybean genes that were differentially regulated following SBR infection were identified by mixed model analysis, and q-values were used to set a stringent false discovery rate of 0.001 percent. Using these criteria, 19% of the soybean genes represented on the array were differentially regulated following inoculation with SBR in either one or both interactions. Temporal expression profiles revealed that differential gene expression occurred early in both interactions, was reduced at 24 hours after inoculation, and was again observed during later stages of infection. Functional classification of these genes revealed biological processes that are important to resistance and susceptibility of Rpp3-containing soybean plants to SBR. Together this information will help prioritize the list of genes to be tested for their function in resistance to SBR and other pathogens.