关键词: 珙桐, AFLP, 遗传多样性, 居群, 遗传分化

Abstract: We analyzed the genetic diversity of six natural and two artificial populations of the endangered plant species，Davidia involucrata Baill. using the AFLP method. A total of 506 reproducible bands of 100–500 bp were obtained with seven AFLP primer combinations，of which 488 bands were polymorphic with a proportion of 96.44%. The percentage of polymorphic bands in different populations ranged between 52.77%–79.25% with an average of 67.00%. At the species level，the Nei’s genetic diversity（H_s）is 0.3429，and the Shannon’s information index（I）is 0.5107；At the population level，the Nei’s genetic diversity ranged from 0.2229 to 0.3389 with an average of 0.2748，and the Shannon’s information index from 0.3219 to 0.4877，averaging 0.3995. The differentiation coefficient（G_st）among the populations was 21.60% and the gene flow（N_m）1.8. The results showed that there was a high genetic diversity in D. involucrata，and genetic differentiation and gene flow were found between the eight populations，but the genetic differentiation occurred mainly within each population. No molecular markers were found between D. involucrata and D. involucrata var. vilmoriniana.

Key words: Davidia involucrata, AFLP, genetic diversity, population, genetic differentiation