Molecular Characterization of All-Stage and Adult-Plant Resistance Loci Against Powdery Mildew in Winter Wheat Cultivar Liangxing 99 Using BSR-Seq Technology
Xiaohan Shi, Peipei Wu, Jinghuang Hu, Dan Qiu, Yunfeng Qu, Yahui Li, Yi Liu, Tesfay Gebrekirstos Gebremariam, Jingzhong Xie, Qiuhong Wu, Hongjun Zhang, Hongwei Liu, Li Yang, Guozhong Sun, Yang Zhou, Zhiyong Liu, Hongjie Li
Abstract
Winter wheat cultivar Liangxing 99, which carries gene Pm52, is resistant to powdery mildew at both seedling and adult-plant stages. An F 2:6 recombinant inbred line population from cross Liangxing 99 × Zhongzuo 9504 was phenotyped with Blumeria graminis f. sp. tritici isolate Bgt27 at the adult-plant stage in four field tests and the seedling stage in a greenhouse test. The analysis of bulk segregant RNA sequencing (BSR-Seq) identified a single-nucleotide polymorphism-enriched locus, Qaprpm.caas.2B, on chromosome 2BL in the same genomic interval of Pm52 associated with the all-stage resistance (ASR) and Qaprpm.caas.7A on chromosome 7AL associated with the adult-plant resistance (APR) against the disease. Qaprpm.caas.2B was detected in a 1.3 cM genetic interval between markers Xicscl726 and XicsK128 in which Pm52 was placed with a range of logarithm of odds (LOD) values from 28.1 to 34.6, and the phenotype variations explained in terms of maximum disease severity (MDS) ranged from 45 to 52%. The LOD peak of Qaprpm.caas.7A was localized in a 4.6 cM interval between markers XicsK7A8 and XicsK7A26 and explained the phenotypic variation of MDS ranging from 13 to 16%. The results of this study confirmed Pm52 for ASR and identified Qaprpm.caas.7A for APR to powdery mildew in Liangxing 99.