Genotypic Variation And QTL Mapping Of Potassium Use Related Traits In Wheat

Genotypic variation of K use related index of some wheat varieties which were promotedin China’s Huang-Huai Wheat Region over the past decade were studied by hydroponicculture and field trials. And the characteristics of the different index were discussed in theevaluation of potassium efficiency; At the same time, a set of131“Shannong483×Chuan35050” recombinant inbred lines (RIL) were used to identify the QTL for potassium userelated traits at seedling stage and maturing stage under different potassium treatments andstudy the genetic linkage between seedling growth and grain yield of wheat under differentpotassium treatments. The test has verified the basic genetic characteristics of K efficiencyrelated traits in wheat, and obtained some valuable QTL with K efficiency related traits Theseresults will provide theoretical basis for genetic improvement of K efficiency related traits inwheat and provide data support for the marker-assisted selection and map-based cloning ofmajor QTL. The main results of study are as followed:1. The are significant genotypic variation among potassium use related index. The totalK accumulation by wheat could be used as a seeding and fleld screening index.2. The correlation coefficient of TGW, GN and SN were lower in the genetic process, thegeneral contributions of lower9%to phenotypic variation. They had a strong independenceand were no absolute trade-off phenomenon. Therefore, for the three elements of output-TGW, GN and SN, improved single even three traits simultaneously have theory possible.3. Six seedling traits under hydroponic culture trial of two K treatments, and10yieldtraits in a pot trial of three K concentrations were investigated. A total of25QTLs forseedling traits and59QTLs for yield traits were detected. These QTLs distributed on all thewheat chromosomes except the chromosomes3D,4D and6D.4. The vast majority of QTL for the same trait detected under different K levers are notthe same, which showed that the same traits under different K treatments were controlled bydifferent QTL/gene. But there also existed QTL which were detected simultaneously underdifferent K treatments, thest sites are stable, and can control the same traits under different Ktreatments. Some QTLs with different traits were mapped in the same or closedchromosomal regions, which suggested that these regions may control multiple traitssimultaneously. There exist obvious linkage relationship between seeding traits (SDW,RSDW, SKC, TKC and KUE) and adult stage traits (TGW, GN, SN, GWP, StWP, StKC, AGKC, GKUE and StKUE) of QTLs. Seven QTL clusters were referred simultaneously toseedling traits and yield traits, which should be the constitutive expression loci at the wholestage of plant growth and development. The founding of constitutive expression loci providedgenetic evidence for that seedling traits influenced yield improvement at maturity. These areasare the hot regions controlling wheat K efficiency related traits, and worthy of further study.