Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Use of covariances between predicted breeding values to assess the genetic correlation between expressions of a trait in 2 environments | 353 Genet Sei Evol 1993 25 353-372 Elsevier INRA Original article Use of covariances between predicted breeding values to assess the genetic correlation between expressions of a trait in 2 environments DR Notter c Diaz Virginia Polytechnic Institute and State University Department of Animal Science Blacksburg VA 2406I USA Received 23 June 1992 accepted 23 March 1993 Summary - Procedures to interpret correlation and regression coefficients involving predicted breeding values BV calculated for the same animals in different environments have been developed. Observed correlations are a function of the additive genetic correlation between performances in the 2 environments but are also affected by selection of animals that produce data in both environments the accuracy of BV predictions in each environment relationships among animals within and across environments and covariances among BV predictions within an environment arising from estimation of fixed effects in best linear unbiased prediction BLUP of animal BV. Methods to account for effects of selection and variable accuracy and experimental designs to minimize effects of relationships and covariances among BV predictions from estimation of fixed effects have been described. The regression of predicted BV in environment 2 on predicted BV in environment 1 is generally not affected by selection in environment 1 but both correlation and regression coefficients are sensitive to covariances among breeding value predictions within environments. In general caution must be exercised in interpreting observed associations between predicted breeding values in different environments. predicted breeding value genetic correlation regression selection index best linear unbiased prediction Resume Utilisation des covariances entre les valeurs génétiques prédites pour estimer la correlation génétique entre les expressions d un caractère dans 2 milieux. Des procedures sont établies pour interpreter les coefficients de correlation et
