小麦萌发期抗旱和耐盐性状的QTL分析

该研究以‘山农0431×鲁麦21’RIL群体及其父母本为材料,用20%PEG-6000溶液和100 mmol·L-1 NaCl溶液分别模拟干旱和盐环境,对12个小麦萌发期抗旱耐盐相关性状进行测定,结合已构建的分子标记遗传图谱对小麦萌发期抗旱、耐盐的相关性状进行QTL分析,为小麦抗旱、耐盐基因的克隆和分子标记辅助选择提供参考。结果表明:(1)正常、干旱和盐胁迫3种处理下共检测到143个QTL。检测到相对高频QTL(RHF-QTL)29个,平均贡献率范围为4.39%~13.28%,贡献率在10%以上的主效RHF-QTL有10个。(2)检测到胁迫下特异表达的RHF-QTL共17个,正常处理下特异表达的RHF-QTL为8个,稳定表达的RHF-QTL为4个。(3)QTL分析结果表明,7个RHF-QTL形成了3个QTL簇,且分布在2D、4D和5B等3条染色体上,其中:QC1位于2D染色体的wPt-6847~D-1172783区间,包括3个QTL(QRl-2D.2、QSdw-2D.3、QTdw-2D);QC2位于4D染色体短臂的D-2245724~D-1108531区间,包括2个QTL(QSl-4D、QShl-4D);QC3位于5B染色体的D-982263~S-1083095区间,包括2个QTL(QSl-5B.2、QTdw-5B.1)。

QTL Mapping of Drought and Salt Tolerant Traits in Wheat at Germination Stage

In this study,the test material was carried out using RILs(recombinant inbred lines)derived from the cross of‘Shannong 0431×Lumai 21’.Drought and salt environments were simulated with 20%PEG-6000 solution and 100 mmol·L-1 NaCl,respectively.We analyzed quantitative trait loci(QTL)for drought and salt tolerant related traits in wheat on the 12 drought and salt tolerant traits in wheat germination,combining with a genetic map constructed by our group,to provide references for the cloning of salt-tolerant and drought-resistant genes and marker-assisted selection of wheat.The results showed that:(1)a total of 143 QTLs were detected for 12 traits under normal,drought and salt environments.A number of 29 RHF-QTLs were detected with the average contribution rate ranged from 4.39%to 13.28%.Among them,the contribution rate of 10 RHF-QTLs was more than 10%.(2)A total of 17 and 8 RHF-QTLs with specific expression were detected under stress and normal treatments,respectively.Four RHF-QTLs with stable expression were detected.(3)A number of three QTL clusters formed by 7 RHF-QTLs were detected,distributing on chromosomes 2D,4D and 5B.Among them,QC1 was located in the wPt-6847-D-1172783 of 2D chromosome,including three QTLs(QRl-2D.2,QSdw-2D.3,QTdw-2D).QC2 was located in the D-2245724-D-1108531 of 4D chromosome,including two QTLS(QSl-4D,QShl-4D).QC3 is located in D-982263-S-1083095 of chromosome 5B chromosome,including two QTLS(QSl-5B.2,QTdw-5B.1).