Inheritance and correlation analysis of genotype × environment interaction for nitrogen metabolism-related traits of wheat

【Objective】 Selection of wheat cultivars of high nitrogen utilization is essential for the improvement of nitrogen fertilizer use efficiency and environmental safety. In this study, the genetic effects of nitrogen metabolism-related traits of wheat were analyzed, to provided a theoretical basis for wheat breeding of high nitrogen use efficiency cultivars. 【Methods】 Seven wheat cultivars with different nitrogen use efficiencies and their twelve F1 crosses were used as materials in a pot experiment. Three nitrogen levels were designed, a genetic model was used to calculate the additive and dominance effects and their interaction. 【Results】 The additive effects are the major genetic component for plant height, the dry weights in single stem at the anthesis stage and maturity stage, the nitrogen accumulation in anthesis stage, the nitrogen accumulation in grain and the total nitrogen contents. The total N assimilation amounts after the anthesis are mainly controlled by dominance environment interaction effects, and the nitrogen use efficiency and nitrogen physiological efficiency mainly by additive environment interaction effects. The heritabilities of ten traits in narrow-sense are generally small with a mean of 0.56, but are high in broad-sense with a mean of 0.881. The interaction between the heritability of ten traits in broad-sense is significant at 1%, showing a intense effect on the genetic expression under different nitrogen levels. The narrow-sense heritability interactions for the nitrogen use efficiency, nitrogen physiological efficiency and nitrogen assimilation amount after the anthesis are high, showing the different selection results of nitrogen levels to the wheat traits. The additive effect forecast shows the significant positive interaction of DK138 and JN10 in N use efficiency and N use physiological efficiency. The dominant effects in most crosses do not always show agreeable directions with those in the interactions of domestic environmental factors, which indicate that the selection of wheat traits with high N efficiencies should consider the supply levels of nitrogen. The dominance effects of the nitrogen physiology efficiency on cross JN10W9903 are maximum and reach significant level, showing high nitrogen physiology efficiency. The cross LM14W9903 exhibits expecting potential for the selection of desirable progenies according the values of dominance effect. The correlation analysis indicates the predominance effects of additive correlation among traits. The nitrogen physiological efficiency and plant height show positive additive correlations which reach the significant level at 10%. Except the plant height and glutamine synthetase activity, the nitrogen use efficiency and other traits are given priority to dominant environment interaction correlation. The correlations between nitrogen use efficiencies and phenotypic and genotypic nitrogen physiological efficiencies are positive significantly. 【Conclusions】 The plant height can be used as indirect selection traits of nitrogen physiological efficiency to a certain extent. Both the genotypic nitrogen use efficiency and nitrogen physiological efficiency traits could be improved simultaneously. The DK138 and JN10 can be used as parents to breeding cross progenies with high nitrogen use efficiency and nitrogen physiological efficiency. Cross LM14W9903 has good potential of selecting progenies according to the values of dominance effect.