Evaluation of genetic diversity and identification of QTL controlling seed germination and seedling establishment traits in wheat

In order to study genetic diversity and identification of QTL controlling seed germination and seedling establishment traits in wheat 148 bread wheat RILs and their parents (RojoYecora and No.49) were studied based on an alpha lattice design with two replications under normal and drought stress conditions in 2016. In this research final germination percentage, germination speed, root and shoot length, root and shoot dry weight and seedling dry weight and vigor index were measured. Analysis of variance showed that between genotypes for all traits, there were significant differences. Under normal moisture conditions the highest heritability was observed for stem length, stem weight and final germination percentage. The highest heritability under drought conditions was found for root length. QTL analysis using composite interval mapping (CIM) for each trait in each environment and mean of two environments were performed. Under normal conditions16 QTL were detected. Phenotypic variance explained by the identified QTLs varied from 11.49 to 21.57 percent. The highest and lowest phenotypic variation belonged to shoot dry weight and root dry weight, respectively. The estimated LODs were in range of 3.15 to 6.76. Under stress conditions 20 QTL were detected. Phenotypic variance explained by these QTLs varied from 11.89 to 24.65 percent. The highest and lowest phenotypic variation were observed fot root dry weight and shoot length respectively. Furthermore LODs were in range of 3.11 to 9.67. Considering the average of two environments, 14 QTL were detected. Phenotypic variance explained by the identified QTLs varied from 11.41 to 23.20 percent, and belonged to root dry weight and shoot dry weight, respectively. The estimated LOD was in range of 3.12 to 7.25. In two different environmental conditions and their average QTL located on chromosome 4B interval markers of Wms121-Sukkula.1300 which control of shoot dry weight and seed vigor and QTL located on chromosome 2D between markers of Gwm349-Wmc445 Which is controlled vigor index was quite stable in all conditions that can be used for marker assisted selection.