QTL Mapping For Salt Tolerant Traitsat Seedling Stage In Wheat

The population used for the QTL for salt tolerance analysis consisted of a set of177RILs derived from ‘‘Shannong0431×Lumai21’’(F8in2011). The main results are asfollowes:The177RILs and their parents were grown under hydroponic culture in greenhouse andoutdoor at ShandongAgriculturalUniversity. There are three treatments for each RIL includedthree Na+concentration gradient(T1CK,T275mM,T3150mM). For each treatment, there arethree repeat. For the RILs, the variance for either genotype or environment effects of all of theten investigated traits were significant at the p≤0.001level, indicating that the environmentsand genetic background were both important in explaining the overall phenotypic variations,and continuous distributions were common for all of the traits in the six environments,indicating the quantitative nature of polygenic inheritance. The simple correlation coefficientsshowed that the SH had a significant positive correlation with the RN, SFW、SDW、RFWandRDW and but a significant negative correlation with the RL and CH. The strong positivecorrelations were simultaneously obtained between the RL and SFW、SDW、RFW、RDW.Significant negative correlations were found between the RN and SFW、SDW、RFW、RDW.The correlation between the SFW、SDW、RFW、RDW were significant, and had a significantpositive correlation with CH.A total of282QTLs were detected on19chromosomes (except for1D and3A) for all ofthe investigated traits. A single QTL in different environments explained3.27～84.9%of thephenotypic variations. Of which,143QTLs showed positive additive effects with Shannong0431increasing the effects of QTLs, whereas139QTLs were negative effects with Lumai21increasing the QTL effects. In the present study,20QTLs for SH、34QTLs for RL、27QTLsfor RN、34QTLs for SFW、24QTLs for RFW、25QTLs for SDW、24QTLs for RDW、29QTLs for SK/Na、31QTLs for RK/Na、36QTLs for CH.Among them,18QTLs (QSh-4A、QSh-5B、QRl-2B、QRl-4B、QRfw-3D、QRfw-5A、QRfw-5B、QSfw-5B、QSfw-5A、QRn-7A、QSdw-5B、QRK/Na-3D、QRK/Na-1A、QRK/Na-5D、 QSK/Na-4A、QCh-4A、QCh-4B、QCh-5B、QCh-2A) were detected in more than four treatment-experiments, andmost of the18QTLs made large contributions of approximately10%. Surprisingly,QRK/Na-3D、QRK/Na-5D、QSK/Na-4A explained as much as52.8%、42.8%、55.5%of thephenotypic variation, respectively.Despite the QTLs were distributed widely throughout the wheat genome, thirteen clusters included three or more QTLs were identified on five chromosomes, specifically,1A(2)、2B、3D(2)、4A、4B、5A(2)、5B(2)、5D、6A.