A terminal deletion in wheat chromosome arm 3BS contains gene YrJ262 conferring adult plant resistance to stripe rust.

Wheat stripe (or yellow) rust, caused by Puccinia striiformis f. sp. tritici, imposes a major constraint on wheat production. While race-specific seedling resistance genes can be effective in controlling this disease, those conferring resistance at the adult stage typically protect the host from infection by a broad spectrum of the pathogen, and tend to be more durable. But the durable resistance such as that expressed by the recently developed Chinese cultivar (cv.) Jimai 262 is poorly understood. Based on the identification of a spontaneous loss-of-function mutant, a genetic analysis indicated that cv. Jimai 262's adult plant resistance to stripe rust is conferred by the presence of a single dominant gene, tentatively designated YrJ262. Bulk segregant exome sequencing implied that the distal end of chromosome arm 3BS of the mutant lacked a ~ 73 Mbp segment that was present in cv. Jimai 262, thereby placing YrJ262 within this segment. The presence of this deletion was confirmed by fluorescence in situ hybridization-based analysis. The flanking sequences of the Yr30 candidate region were identical between plants carrying Yr30 and cv. Jimai 262. YrJ262 was complemented by alleles present within QTL on cv. Jimai 262 chromosomes 1B and 4B enabling the expression of adult plant resistance.