RAPD ANALYSIS ON GENETIC DIVERSITY OF CARYA DABIESHANENSIS POPULATIONS
大别山山核桃种群遗传多样性研究

The genetic diversity and genetic variation within and among three natural Carya dabieshanensis populations were studied using RAPD analysis. The result showed that 238 loci were detected by using 20 random primers (10 bp) of which 162 loci were polymorphic (68.1%). Species genetic diversity indicated by Shannon's index was 0.476 1, 58.18% of which was due to within population genetic diversity and 41.82% among population variation. Species gene diversity indicated by Nei's index was 0.314 5, gene diversity within populations (H_S) was 0.186 5, gene diversity among populations (H_ ST) was 0.128 0 and the coefficient of gene differentiation (G_ ST) among the populations was 0.406 7, 59.33% of which was within populations and 40.67% was among populations. The gene diversity estimated by Nei's index was consistent with that estimated by Shannon's index. These results suggest that there is rich genetic within population variation, which offers excellent prospects for seeding selection. The estimate of gene flow from G_ ST (N_m) was 0.730 6, indicating that genetic recombination between populations is quite small, which probably is related to environmental adaptations of C. debieshanensis and population isolation in their high mountain habitat.