No abstract

Kalopanaxpictus (Araliaceae) is a long-lived woody species primarily distributed throuBhout East Asia. This species isregarded as medically and ecologlcally important in Korea. We used starch gel electrophoresis to invesUgate its ailoz. yme variation and genetic structure in samples from Korean populations (both natural and cultivated). Our analysis of 10 enzymes revealed 18 loci, of which 10 were polymorphic (55.6%). Genetic diversity at the species and population levels were 0.200 and 0.149, respectively, with the mean for cultivated populations (0.124) being lower than for natural (wild) populations (0.181). Asexual and sexual reproduction modes, perennial habitat, and Iongevib/all were possible factors contributing to such high diversity. An indirect estimate of the number of migrants per generation (Nm : 1.08) indicated that gene flow was not extensive arnon 8 these Korean populations. Therefore, we suBgest that geographical distance as well as reproductive isolation between wild and cultivated plants may play roles in shaping the population structure of this species.

These parameters of genetic diversity indicate that the cultivated populations are genetically depauperate relative to their presumptive progenitor, and that the domestication process has partly eroded the level of genetic variation of this species. Nevertheless, the diversity of this species has higher-than.average values compared with other species having similar life-history traits.We propose that the mix-mating system; perennial, high gene flow; and large population sizes are possible factors contributing to this high diversity, which seemed to increase with distance from the coastlines.

No abstract

Most plants, especially rhizomatous and .st ol()niferous species, have physical connections among ramels although the level of persisten(~ is highly variable among species and habitats (Sobey and Barkhouse, 1977). Studies on the geneti( structure of ap()nlicti( plant tx)pulations have received increase(i interest over the past decade with the advent of electrophoretic techniques, which allow us to better access the genotypic composition of populations. A wellestabli.~hed general belief has been that asexuallyreproducing species lack genetic diversity and can be considered as evoluti()nary "dead-ends". Vari()us studies have shown that asexually-reproducing plants can be much more geneti(:ally diw~rse than originally thought (EIIstrand and Roose, 1987). Clearly, descriptive genetic work on both sexual and asexual plant populations is needed as well. Despite the imD)rtance of genetic variation data for conservation purposes and population genetk structure, detailed studies of the levels and distributi()n of genetic variation have not been t)efformed on most H}ecies in Korea, and are particularly lacking for plants with both sexually -and asexually-reprodudive ability (Chung el al., 1995;.The genus Potentilla is a large, diverse family