Study on Grain-leaf Area Ratio and the Yield Traits of Wheat Cultivars with Different Spike Types under Close Planting Conditions

The grain-leaf area ratio and its correlation with the yield trait of 12 high-yield wheat cultivars with different spike types broadly planted in Henan province were measured under close planting conditions in this study.The results showed that there was significant difference in the grain-leaf ratio among multi-spike wheat cultivars,mid-spike wheat cultivars and big-spike wheat cultivars.The ratio of spike grain weight to flag leaf area(SGW/FLA) and grain number per spike to flag leaf area(GNPS/FLA) were positively correlated to the grain yield,and the positive effects were significantly higher than the ratio of spike grain weight to the top two leaf areas and grain number per spike to the top two leaf areas.These indicated that GNPS/FLA and SGW/FLA could be more effective selection factors in the wheat breeding,and the suitable ranges were 1.521-1.879 grains/cm2 and 0.076-0.089g/cm2,respectively.The heritability of grain-leaf arearatio was at middle-low level and there was some variance in its genetic coefficient.