Authors: Yingjun Zhang Xianchun Xia Zhonghu He
Publish Date: 2016/09/20
Volume: 130, Issue: 1, Pages: 81-89
Abstract
Preharvest sprouting PHS affects yield and enduse quality in bread wheat Triticum aestivum L In the present study we found an association between the TaSdrA1 gene and PHS tolerance in bread wheat TaSdrA1 on chromosome 2A was cloned using a homologous cloning approach Sequence analysis of TaSdrA1 revealed an SNP at position 643 with the G allele being present in genotypes with lower germination index GI values and A in those with higher GI These alleles were designated as TaSdrA1a and TaSdrA1b respectively A cleaved amplified polymorphism sequence CAPS marker Sdr2A based on the SNP was developed and linkage mapping and QTL analysis were conducted to confirm the association between TaSdrA1 and seed dormancy Sdr2A was located in a 29 cM interval between SSR markers Xgwm95 and Xgwm372 A QTL for GI at the TaSdrA1 locus explained 66 73 and 82 of the phenotypic variances in a Yangxiaomai/Zhongyou 9507 RIL population grown at Beijing Shijiazhuang and the averaged data from the two environments respectively Two sets of Chinese wheat cultivars used for validating the TaSdrA1 polymorphism and the corresponding genespecific marker Sdr2A showed that TaSdrA1 was significantly associated with GI Among 29 accessions with TaSdrA1a 24 828 were landraces indicating the importance of Chinese wheat landraces as sources of PHS tolerance This study identified a novel PHS resistance allele TaSdrA1a mainly presented in Chinese landraces and it is likely to be the causal gene for QPhsccsu2A3 providing new information for an understanding of seed dormancyWe thank Prof R A McIntosh Plant Breeding Institute University of Sydney for review of this manuscript This study was supported by the National Natural Science Foundation of China 31461143021 31371623 Gene Transformation Projects 2016ZX08009003 2016ZX08002003003 Beijing Municipal Science and Technology Project D151100004415003 National Key Project 2016YFD0101802 Hebei Province Natural Science Fund C2015301009 and Financial Fund of Heibei Province F15R055029
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