Rice breeding against sheath blight is now feasible: a breakthrough discovery of SBRR1-mediated sheath blight resistance from natural rice germplasm.

Abstract

Sheath blight (ShB), caused by the necrotrophic fungus Rhizoctonia solani, is a globally destructive rice disease responsible for significant yield losses. However, the absence of characterized genes conferring high potential resistance to sheath blight within natural rice germplasm constrains resistance breeding. A recent study published in Nature Genetics uncovered the ShB resistance receptor-like kinase 1 (SBRR1) as a key gene associated with disease resistance. SBRR1-R, an elite resistance allele mainly presented in indica rice and distinguished by a 256-bp promoter insertion, confers strong resistance without obvious yield penalty. SBRR1 is the first gene with major effects underlying natural variation in sheath blight resistance, offering significant potential for rice breeding. Furthermore, the discovery of the "bHLH57-SBRR1-R-SIP1-Chit3/4" defense module provides fundamental insights into rice immunity and a molecular module with substantial breeding potential.