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本文探讨了应用通径分析制订几个性状同时进行选择的综合选择指数。它是根据复合育种值H=sum from j=1 to m a_j A_j与综合选择指数I=sum from i=1 to n b_i x_i之间的相关RHI最大来确定b_i,以选择指数I大的个体作为种畜。为了利用通径分析确定加权系数b_i,需要提供如下的不同性状的参数,以构成最有效的选择指数: 1、不同性状的遗传力(h_i~2), 2、各性状的表型标准差(σi), 3、各性状的相对育种重要性(σi); 4、各性状间的表型和遗传相关(Υij和ΥAij)。根据上边的信息,首先求出复合育种值的方差(σ_H~2)及各性状表型值与综合育种值的相关(YiH),然后计算各性状与复合育种值的通径系数(PH·xi),最后根据通径系数求出偏回归系数(bi)。如果根据RHI进行检验是显著的,I就是一个理想的选择指数。
This article discusses the use of path analysis to develop several traits while selecting the comprehensive selection index. It is based on the composite breeding value H = sum from j = 1 to m a_j A_j and the comprehensive selection index I = sum from i = 1 to n b_i x_i between the maximum correlation RHI to determine b_i to select individuals with a large index I as Breeding animals. In order to determine the weight coefficient b_i using the path analysis, the following parameters of different traits need to be provided to form the most effective selection index: 1, the heritability of different traits (h_i ~ 2), 2, the standard deviation of the phenotype of each trait σi), (3) the importance of relative breeding of each trait (σi), and (4) the phenotypic and genetic correlation among the traits (γij and γij). According to the above information, the variance (σ_H ~ 2) and the correlation (YiH) between the composite breeding value and the value of the composite breeding value were calculated first, and then the path coefficient (PH · xi ) Finally, according to the path coefficient to find the partial regression coefficient (bi). If the test based on RHI is significant, I is an ideal choice index.