A parameter for measurement of genetic differences between parents is introduced, ie: ω/(2 μ)=heterosis over mid-parent value-heterosis over better-parent value=(D_(ij)-(D_(ii)+D_(jj)/2)/μ-(F_1-MP-ω/2)/μ; The assessment of genetic relationship among tropical a.
采用混合线性(AD)模型,和MINQUE(1)法(Minimum Norm Quadratic Unbiased Estimation,最小范数二阶无偏估算法)分析了9个热带亚(温)带玉米群体2年2点双列杂交设计的非平衡数据,估算了产量及其构成因素的遗传方差分量和F1基因型值,并对群体平均优势和群体超亲优势也进行了估算;引入亲本遗传差异的度量参数:ω/(2μ)=群体平均优势-群体超亲优势=[D_(ij)-(D_(ii)+D_(jj))/2]/μ-(F_1-MP-ω/2)/μ;通过估算F1群体平均优势和群体超亲优势,得到群体(亲本)间的遗传差异,从而,对这些群体间的遗传关系做出了评价。