Qtl Mapping Of Wheat Spike Traits In A New Germplasm From The Cross Between Common Wheat And Agropyron Cristatum

Spike-related traits are the important agronomic traits of wheat, which are the important research direction in increase wheat yield and variety improvement. At the same time, distant hybridization variety as research materials are also the most important means in germplasm innovation and breeding of the wheat.In the study, as a new wheat derivative Line'3558-2' from the cross between common wheat Variety Fukuho and Agropyron cristatum Z559 the research materials. It is not only can control the development of effective tillers, but also possess the elite traits of more kernel number per spike. In order to reveal the genetic feature of spike traits in Line '3558-2', Using major gene plus polygene mixed linear model analysis, single marker analysis and composite interval mapping methods, researth a population with 282 F2 lines derived from the cross between'3558-2'and 'Jing 4841', that was used to genetic analysis and QTL mapping about Spike length, Spikelet number per spike, Kernel number per spikelet and Kernel number per spike traits.The main results as following:1. The analysis results of the major gene plus polygene mixed linear model indicate that these spike traits are all accord with the feature of quantitative traits.2. QTL mapping results show that four QTLs were detected on chromosomes 1A, including Spike length, Spikelet number per spike, Kernel number per spikelet, Kernel number per spike, which explain 14.41%,5.15%,14.84% and 10.87% of phenotypic variance respectively. Most of QTL's phenotypic variance exceed 10%, that indicate those QTLs are major sites. Dominance effect are 0.1084,-0.3922, 0.2310 and 1.8184 respectively, show that most of traits come from wheat derivative Line'3558-2'3. Interestingly, the research find two elite gene clusters on 1AS chromosome contained the traits of Spike length, Spikelet number per spike, Kernel number per spikelet, Kernel number per spike, and effective tillers as well. The results suggest that Line '3558-2'carry elite gene cluster in 1AS chromosome and can be a good germplasm resource for wheat improvement.