Identification of a major QTL for flag leaf glaucousness using a high-density SNP marker genetic map in hexaploid wheat

摘要

cqvip:Cuticular wax plays an important role in protecting land plant against biotic and abiotic stresses. Cuticular wax production on plant surface is often visualized by a characteristic glaucous appearance. This study identified quantitative trait loci(QTLs) for wheat(Triticum aestivum L.) flag leaf glaucousness(FLG) using a high-density genetic linkage map developed from a recombinant inbred line(RIL) population derived from the cross Heyne×Lakin by single-seed descent. The map consisted of 2 068 single nucleotide polymorphism(SNP) markers and 157 simple sequence repeat(SSR) markers on all 21 wheat chromosomes and covered a genetic distance of 2 381.19 c M,with an average marker interval of 1.07 c M. Two additive QTLs for FLG were identified on chromosomes 3AL and 2DS with the increasing FLG allele contributed from Lakin. The major QTL on 3AL,QFlg.hwwgr-3AL,explained 17.5–37.8% of the phenotypic variation in different environments. QFlg.hwwgr-3AL was located in a 4.4-c M interval on chromosome 3AL that was flanked by two markers IWA1831 and IWA8374. Another QTL for FLG on 2DS,designated as QFlg.hwwgr-2DS which was identified only in Yangling in 2014(YL14),was flanked by IWA1939 and Xgwm261 and accounted for 11.3% of the phenotypic variation for FLG. QFlg.hwwgr-3AL and QFlg.hwwgr-2DS showed Additive×Environment(AE) interactions,explaining 3.5 and 4.4% of the phenotypic variance,respectively. Our results indicated that different genes/QTLs may contribute different scores of FLG in a cultivar and that the environment may play a role in FLG.