The Demographic Genetics of Liatris cylindracea Michx. (Compositae)

Abstract

The demographic genetics of a population of L. cylindracea were studied. The population has a nonstable age structure; there is a deficiency of young plants. Plants are divided into 6 age classes and the average heterozygosity of each age class measured at 27 allozyme loci. Average heterozygosity increases with increasing age class while FST, the standardized genetic variance, decreases. In addition, a positive relationship was found between individual heterozygosity and fecundity, longevity and speed of development. Both age and reproductive potential are positively correlated with individual heterozygosity; plants flowering after 2 seasons are more heterozygous than plants which do not flower. It is concluded that individual heterozygosity is being selected for.