Pooni H S, Jinks J L
Heredity (Edinb). 1986 Dec;57 ( Pt 3):341-4. doi: 10.1038/hdy.1986.133.
Accurate estimates of the true additive genetic variance (sigma ki = 1 d2i) of a cross between two pure breeding varieties can be obtained from the additive genetic components of the first three ranks (D1, D2 and D3) when the latter are biased by the presence of linkage. Additive genetic variances of the lower ranks are directly equatable with sigma ki = 1 d2i because they incur minimal bias even when the predominating linkages are strong. More precise estimates of sigma ki = 1 d2i are however obtainable from the asymptotic regression analysis or a weighted least squares analysis. Estimates of sigma ki = 1 d2i when obtained from 784 hierarchically derived F7 families of the V2 X V12 cross of Nicotiana rustica were observed to be considerably larger than the additive genetic variance displayed by the F13 inbreds of the same cross for all the characters that showed significant excess of repulsion linkages. These results lend support to our commonly held view that the prediction procedures generally underestimate the probability of successful recovery of superior recombinant inbreds.
当两个纯育品种之间杂交的真实加性遗传方差（sigma ki = 1 d2i）因连锁的存在而产生偏差时，可从前三个秩次（D1、D2和D3）的加性遗传成分中获得其准确估计值。较低秩次的加性遗传方差可直接等同于sigma ki = 1 d2i，因为即使主要连锁很强，它们产生的偏差也最小。然而，通过渐近回归分析或加权最小二乘法分析可获得sigma ki = 1 d2i更精确的估计值。当从784个烟草V2×V12杂交组合的分层衍生F7家系中获得sigma ki = 1 d2i的估计值时，对于所有表现出显著过量相斥连锁的性状，观察到该值远大于同一杂交组合的F13自交系所显示的加性遗传方差。这些结果支持了我们普遍持有的观点，即预测程序通常低估了成功获得优良重组自交系的概率。
