云南松的种群遗传与进化

本文从种群遗传学的角度研究了云南松（pinus yunnanensis)的遗传体制，种群内的多态现象，种群的遗传结构，演化潜力，生态小种和地理小种以及共交种等问题，得出的若干结论如下：（1）种内存在巨大的遗传变异，如在自然 群中表明的，几乎所有可见的形态性状都具有多态现象，这种巨大的遗传变异是自然选择进化的一个必要条件。（2）自然种群中，大多数个体的基因型很多座位都是杂合的，它们常表现出杂种优势，并且也可能表明增强了生理上发育上的体内平衡。（3）由于种群大，而且又分割成许多相对独立的亚群，各种进化要素都有能同时起作用，并已分化出生态种和地理小种，（4）云南松具有拟态种子，其起源和适应意义作了初步讨论。

The Population Genetics and Evolution of Pinus Yunnanensis

t The problems with genetic system, polymorphism in population, genetic strucre in population, evolutionary potential, ecolgical and geographic race, and cenospecies of Pinus yunnanensis have been studied from the point of view of population genetics on this paper. Some conclusion have been drawn. Among these are the follows. (1)A great deal of genetic variation exsts in this species, as indicated by polymorphism of almost every visible characteristics in natural populations, That is a necessary condition for evolution by natural selection. (2)The majority of individuals in natural population should have the genotypes with heterozygous loci. They often manifest hybrid vigor andincrease physiological or development homeostasis. (3)A11 the evolutionary factors could operate simultaneously,because the populations of Pinus yunnanensis are large and subdivided into a number of partially isolated groups, so that this species not only has sufficient current fittness but also high evolutionary flexibility and great evolutionary potential. The ecological and geographic race have been differentiated. (4)There exist mimetic seeds in the species. The origin and adaptive signficance of mimetic seeds have been discussed.