The Genetic Analysis Of Agronomic Traits And Yield Of Edible Sunflower

Sunflower is one of the world major annual crops grown for snacking and edible oil and its meal is a potential source of protein for human consumption. It contains tocopherol that decreases potential risk of chronic diseases in human. The research used 8 inbred lines of the edible sunflower which had rich genetic background to make up 16 cross combinations according to incomplete diallel cross, constructed the analysis of genetic populations. The genetic model of Additive-Dominance considering Gene-Environment interaction was used for genetic and correlation analysis of the 10 agronomic traits and yield on edible sunflower, and the method of multivariate conditional analysis was applied for genetic contribution analysis of agronomic traits to seed yield.So as to provide reference for the utilization of the heterosis in edible sunflower breeding and inbred lines selection. The main research results were as the followings.1. Eleven traits, such as plant height, growth period, seeds per disc, fertility, 100-achene weight, seed weight per disc, hull percentage were mainly controlled by additive effect. For additive effect, it was predominant on kernel percentage and hull percentage, while it was slightest on yield.For dominance effect, the yield was mainly controlled by the dominance effect and dominance×environment effect, it was predominant on disc diameter, while it was small on kernel percentage and hull percentage.2. Seeds per disc performed significantly positive additive effect in parents of R121828、R1210368、R1011393、KJR1301 and 101033 R, the stem diameter perfored significantly positive additive effect in the parents of T1210395 、 KJR1301 and 101033 R. The dominance variance component ratios were much higher than the additive variance component ratios of the cross combinations on yield. At the F1 and F2 generations, disc diameter and seed yield showed positive heterosis over mid-parent value and over better-parent value significantly, about two generations are expected, heterosis of genotypes can relatively stable inherited. Fifty percent combinations which showed significant or highly significant difference on positive effect of the seed yield at the two environments were potential cross combinations for seed yield.3. The analysis of correlation among yield and seed percentage,seed weight per disc,seeds per disc,100-achene weight, kernel percentage revealed that most of phenotypic and genotypic correlation, except for day to maturity and hull percentage, between 0.534-0.728 and 0.536-0.731 respectively. The yield only had additive correlation with plant height for significantly additive effect, and had negative correlation with growth period for significantly additive effect, At the same time, yield showed additive correlation with growth period, plant height, disc diameter, seed percentage, seed weight per disc, 100-achene weight for significantly dominant effect, and negatively related to seeds number per disc for significantly dominant effect.4. The analysis of heterosis revealed that all the traits showed positive heterosis over mid-parent value and over better-parent value significantly in the F1 and F2 generations, except for the hull percentage and kernel percentage, all the traits showed positive heterosis over better-parent value significantly, but most of traits performed for negative heterosis over better-parent value. The strength of F1 heterosis had additive correlation with the decreased strength of F2 heterosis, the residual heterosis of F2 individual character were still very considerable.5. The highest contribution to yield additive effect was stem diameter. Disc diameter highly contributed to yield additive effect of three parents. The disc diameter and 100-achene weight of most cross combination had a high level of contribution value to yield were controlled by the dominance effect that can be used as the selection of cross combination production index. Fertility can be use as the assistant selection trait of crossbreed dominant effect, in terms of increasing yield of crossbreed, dominant effect is more important than additive effect.