de Vienne Dominique, Fiévet Julie B
GQE-Le Moulon, INRAE, Université Paris-Saclay, CNRS, AgroParisTech, 91190 Gif-sur-Yvette, France.
Plants (Basel). 2020 Jul 9;9(7):875. doi: 10.3390/plants9070875.
Heterosis (hybrid vigour) is a universal phenomenon of crucial agro-economic and evolutionary importance. We show that the most common heterosis coefficients do not properly measure deviation from additivity because they include both a component accounting for "real" heterosis and a term that is not related to heterosis, since it is derived solely from parental values. Therefore, these coefficients are inadequate whenever the aim of the study is to compare heterosis levels between different traits, environments, genetic backgrounds, or developmental stages, as these factors may affect not only the level of non-additivity, but also parental values. The only relevant coefficient for such comparisons is the so-called "potence ratio". Because most heterosis studies consider several traits/stages/environmental conditions, our observations support the use of the potence ratio, at least in non-agronomic contexts, because it is the only non-ambiguous heterosis coefficient.
杂种优势（杂交活力）是一种具有关键农业经济和进化重要性的普遍现象。我们表明，最常见的杂种优势系数不能正确衡量与加性效应的偏差，因为它们既包含一个解释“真正”杂种优势的成分，又包含一个与杂种优势无关的项，因为该项仅源自亲本值。因此，只要研究目的是比较不同性状、环境、遗传背景或发育阶段之间的杂种优势水平，这些系数就不适用，因为这些因素不仅可能影响非加性效应的水平，还可能影响亲本值。进行此类比较的唯一相关系数是所谓的“强度比”。由于大多数杂种优势研究考虑多个性状/阶段/环境条件，我们的观察结果支持使用强度比，至少在非农艺背景下如此，因为它是唯一明确的杂种优势系数。
