A method is described for deriving the genetic matrix G needed for breeders to select across breeds for any breeding objective. The matrix comprises partitions among selection criteria (G11 ), between selection criteria and the breeding objective traits (G12 ), and among the breeding objective traits (G22 ). A weighting procedure is used to combine the G matrix of individual breeds with known breed differences. Between-breed variances are added to the diagonals of the matrix. Selection across many breeds can be quite different from that across a subset of the breeds. The particular breeds, and the numbers of each breed, that the breeder is prepared to consider in selection changes the genetic matrix and the selection index that should be used.

中文翻译：

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一种推导在品种组合之间进行选择所需的遗传矩阵的方法

描述了一种用于推导育种者为任何育种目标选择不同品种所需的遗传矩阵 G 的方法。该矩阵包括选择标准（G11）之间、选择标准和育种目标性状（G12）之间以及育种目标性状（G22）之间的划分。加权程序用于将单个品种的 G 矩阵与已知品种差异相结合。品种间方差被添加到矩阵的对角线上。许多品种的选择可能与品种子集的选择完全不同。育种者准备在选择中考虑的特定品种和每个品种的数量改变了应该使用的遗传矩阵和选择指数。