Sakai Satoki
Department of Ecology, National Grassland Research Institute, Nishinasuno, Tochigi, 329-27, Japan.
Evolution. 1995 Jun;49(3):557-564. doi: 10.1111/j.1558-5646.1995.tb02287.x.
I present a resource-allocation model to analyze how patterns of allocation to reproductive structures influence the evolution of selfing rates in hermaphrodites subject to competing and delayed forms of self-fertilization. The evolutionarily stable state does not depend on the mode of pollination. In contrast to previous models in which the number and the size of flowers were not considered, intermediate selfing is not evolutionarily stable with linear constraints on flower number and size. In contrast, intermediate selfing can be evolutionarily stable with nonlinear constraints on flower number and size. Optimal allocations to attractive structures increase and selfing rates decrease in the presence of inbreeding depression. In particular, stable intermediate levels of selfing may be favored when flower number is strongly constrained. Thus, nonlinear constraints on flower number and size could favor the evolution of intermediate selfing in either the delayed or the competing modes of selfing. Outcrossing is not favored in the absence of inbreeding depression, a result inconsistent with Holsinger's results in which allocation to attractive structures was not considered.
我提出了一个资源分配模型，以分析对生殖结构的分配模式如何影响雌雄同体植物在面临自花受精的竞争和延迟形式时自交率的进化。进化稳定状态不依赖于授粉方式。与之前未考虑花朵数量和大小的模型不同，在花朵数量和大小存在线性限制的情况下，中等程度的自交在进化上并不稳定。相比之下，在花朵数量和大小存在非线性限制的情况下，中等程度的自交在进化上可能是稳定的。在存在近亲繁殖衰退的情况下，对吸引结构的最优分配增加，自交率降低。特别是，当花朵数量受到强烈限制时，稳定的中等自交水平可能会受到青睐。因此，花朵数量和大小的非线性限制可能有利于在延迟或竞争自交模式下中等自交的进化。在没有近亲繁殖衰退的情况下，异交不受青睐，这一结果与霍尔辛格未考虑对吸引结构分配的结果不一致。
