QTL Mapping Analysis Of Yield-related Traits In Barley

Barley is the main ration of Tibetan compatriots on the Qinghai-Tibet Plateau.Its stable production and increased production are essential for ensuring food security and border stability in the plateau.In view of the current limited genetic basis and the unclear genetic mechanism of barley breeding,the use of excellent germplasm to explore important loci and candidate genes has become one of the key scientific issues in current research.In this study,excellent germplasm Dalimai was used as a common parent,which was derived from cross breeding respectively with Cawangqingke,Dulihuang and Ziliuleng highland barley varieties Recombinant inbred line（RILs）,was constructed based on SNP.The genetic linkage map of the markers was used for QTL mapping of six agronomic traits such as plant height,ear length,tiller number,grain length,grain width and thousand grain weight.The specific research conclusions are as follows:1.There was a significant correlation between agronomic traits in this experiment,among which plant height was significantly correlated with spike length,tiller and grain width,and significantly correlated with thousand grains weight,and the tillering and spike length and grain width were significantly correlated,and the weight of thousand grains was significantly correlated with grain length and grain width,and the correlation Index between thousand grains and grain width was the highest.Pearson correlation coefficient was 0.792;particle length and grain width showed significant correlation.2.Genotyping and genetic linkage map construction of three RILs populations using polymorphic SNP markers.Among them,the total length of the genetic maps of Da li mai× Ca wang qing ke,Da li mai×Du li huang,Da li mai × Zi liu leng group were 897.3 c M,916.5 c M and 826.6 c M,respectively,the average chromosome was 118.09 c M ¹30.93 c M per chromosome,the whole map average mark per 10.6c M 12.06 c M.3.Among the 53 QTL loci detected,24,11 and 18 related QTL loci were detected in the RILs population of the Da li mai× Ca wang qing ke,Da li mai× Du li huang,Da li mai × Zi liu leng.A comparative analysis of the results of the three populations revealed a number of stable genetic QTL loci,including:（SCRI_RS₁19778-SCRI_RS₁43825）on the 4H chromosome simultaneously controlling the panicle length and grain width;localization control in the Da li mai× Ca wang qing ke population The QTL locus QWd.DC-5H of the grain width;the QTL locus controlling the thousand grain weight in the Da limai× Du li huang population: QTkw.DD-3H.Due to the correlation between traits and environmental factors,four QTL clusters were detected,of which SCRI_RS₂35860（SCRI_RS₁71038）-BOPA1₅211-1755 on 2H chromosome simultaneously controlled grain width,thousand grain weight and plant height;SCRI_RS₁53672-BOPA1₄065-397 simultaneously controlled plant height and ear length;SCRI_RS₁19778-SCRI_RS₁43825 on chromosome 4H simultaneously controlled tiller number,ear length,grain width and thousand grain weight.