Conservation Genetic Studies Of Three Endangered Plants

Conservation genetic studies of endangered plants are a key part in the conservation effort for endangered species. Using several molecular markers, genetic variation and population structure of three endangered plant species which were severely disturbed by anthropogenic activities were studied. These baseline data should be essential to understand historical demographic and genetic events, and their interactions on endangered species. The main results are highlighted in the following:1. Berchemiella wilsonii (Schneid.) Nakai var. pubipetiolata Qian (Rhamnaceae) is distributed in fragmented habitat patches in eastern China. It is highly endangered because of severe disturbance by anthropogenic activities. Allozyme variation of population genetic diversity and structure of four extant populations was investigated by using isoelectric focusing in thin-layer polyacrylamide slab gels. Based on 20 loci scored from the nine enzymes examined, a high genetic diversity was detected at both the species and population levels, while there was a loss of low frequency alleles (<0.1) in all populations, possibly due to a recent decrease in population size, and genetic drift in small populations has resulted in a loss of alleles occurring at low frequency.. Most loci showed deviation from Hardy-Weinberg equilibrium due to excess of heterozygotes in all populations, suggesting that selection for heterozygotes and/or severe inbreeding depression have occurred in this species.2. AFLP and cpDNA markers were further used to determine the population structure of remnant populations of B. wilsonii var. pubipetiolata and assess the genetic effects of...