Mapping and characterization of a novel adult-plant leaf rust resistance gene LrYang16G216 via bulked segregant analysis and conventional linkage method

Abstract

Leaf rust (Puccinia triticina) is one of the most devastating fungal diseases of wheat (Triticum aestivum L.). Discovery and identi cation of new resistance genes is essential to develop disease-resistant cultivars. An advanced breeding line Yang16G216 was previously identi ed to confer adult plant resistance (APR) to leaf rust. In this research, a recombinant inbred line (RIL) population was constructed from the cross between Yang16G216 and a highly susceptible line Yang16M6393, and genotyped with exome capture sequencing and 55K SNP array. Through bulked-segregant analysis (BSA) and genetic linkage mapping, a stable APR gene, designated as Lr16G216, was primarily detected and mapped to the distal region of chromosome arm 6BL with a genetic interval of 2.8-cM. For further veri cation, another RIL population derived from the cross between Yang16G216 and a susceptible wheat variety Yangmai 29 were analyzed using the enriched markers in the target interval, and Lr16G216 was further narrowed to a 0.59-cM genetic interval anked by the KASP markers Ax109403980 and Ax95083494, corresponding to the physical position 712.34-713.94 Mb in the Chinese Spring reference genome, in which twenty-six disease resistance-related genes were annotated. Based on leaf rust resistance spectrum, mapping data and physical location, Lr16G216 is identi ed to be a novel and effective APR gene. The Lr16G216 with linked markers will be useful for marker-assisted selection in wheat resistance breeding. Key MessageA novel adult-plant leaf rust resistance gene Lr16G216 on wheat chromosome 6BL was identi ed and mapped to a 0.59-cM genetic interval by BSA and conventional linkage method.

Identification and Characterization of Resistance to Rust in Lentil and Its Wild Relatives

“…Race non-specific adult plant resistance (APR) associated with slow rusting has frequently been exploited in wheat [ 50 , 51 , 52 ]. APR is believed to be more durable for successful long-term rust control [ 53 , 54 ] as it is generally not affected by race, and keeps the disease below the threshold level and decreases the chances of selection of new pathotypes.…”

Deciphering the roles of unknown/uncharacterized genes in plant development and stress responses

“…A leaf rust resistance gene named Lr81 was identified in wheat line PI470121, which is a unique leaf rust resistance locus (Xu et al, 2022a). A stable APR gene, named LrYang16G216, was detected in wheat and identified as a new and effective gene for leaf rust resistance (Zhao et al, 2023b). A gene Pc54 with leaf rust resistance has been identified in oat (Avena sativa) (Admassu-Yimer et al, 2022).These newly identified genes all have excellent activity in inhibiting rust (Figure 4A), which could contribute to the breeding of rust resistant wheat varieties.…”