Mechanisms Underlying Broad Spectrum Resistance

Mechanisms Underlying Broad Spectrum Resistance Genome-wide interactions between Xanthomonas oryzae pv. oryzae (Xoo) and rice resulting from a broad-spectrum hypersensitive reaction (BSHR) mediated by a new rice R gene, Xa39, were investigated by comparative dynamic transcriptomic profiles in the incompatible and compatible interactions using three related rice lines and a highly virulent Xoo isolate, PXO99. Results indicated that the gene network consisted of 27 genes in four groups of distinct functions involving leading to BSHR of rice in the sequential events from the avrXa39 x Xa39 interaction → signal recognition and transduction → protein modification → programmed cell death. Combined evidence suggests LOC_Os11g37759, one of a two-member CC-NBSLRR gene family on rice chromosome 11, as the most likely candidate for Xa39 in rice and two genes, XopN and XopX, involved in the type III secretion system of Xoo as the most likely candidate genes for the corresponding avrXa39 in Xoo. 