Genetic Control of Soybean Innate Immunity

Microbe associated molecular pattern (MAMP)-triggered immunity (MTI) is an important component of the plant innate immunity response to invading pathogens.   However, most of our knowledge of MTI comes from studies of model systems with relatively little work done with crop plants. In this work, we report on variation in both the MAMP-triggered oxidative burst and gene expression across four soybean genotypes. Variation in MTI correlated with the level of pathogen resistance for each genotype. A QTL analysis on these traits identified four loci that appeared to regulate gene expression during MTI in soybean. Likewise, we observed that both MTI variation and pathogen resistance were quantitatively inherited. The approach utilized in this study may have utility for identifying key resistance loci useful for developing improved soybean cultivars, as well new players involved in regulation of plant innate immunity. Indeed, we are now analyzing the functional role of some candidate genes contained within the identified QTL regions.