Population Genetic Diversity And Genetic Structure Of Rhus Chinensis Mill. Based On AFLP Technology

Rhus chinensis Mill.,Belonging to Anacardiaceae, has high medical and economic values.In recent years,the research of Rhus chinensis mainly focused on morphological characteristics,seed breeding, physiology and biochemistry. However, there is little information on its genetic diversity in molecular level.In this study, the genetic diversity and structure of 12 R. chinensis populations (totally 259 individuals) were analyzed using AFLP technique, the results are as following:By doing experiments for several times,the proper system for AFLP analysis of R. chinensis population was established. By comparative test of three DNA extracting methods, the innovated method (4×CTAB) was choosen to isolate the genome DNA of R.chinensis.Using the primer combination methods (E+3/M+3 and E+2/M+3),8 pairs of primers from 96 pairs were selected to amplify the R. chinensis genomic DNA.As a result,12 R. chinensis populations were analyzed by 8 primer combinations using AFLP technique. A total of 372 reproducible bands were got,333 of which were polymorphic with the percentage of 89.52%, which showed that there was high genetic diversity in the species R. chinensis. Longsheng, Wufeng and Taijiang populations had the higher proportion of polymorphic loci.The Gst, Ht and Hs are 0.2478,0.2316 and 0.1742, respectively, which showed that the genetic variation was high between the R. chinensis populations.The Fst (0.2195)and Nm (1.5176) showed that there is high genetic differentiation and limited gene flow between the R. chinensis populations.By AMOVA analysis,6.33% difference was among groups, while 16.98% difference among populations and 76.70% difference within populations, which suggested genetic variation of R. chinensis populations is mainly from intra-populations.Patchy distribution, long-term geographical isolation and the modes of R. chinensis seed transmission et al.,maybe led to higher genetic differentiation of R. chinensis populations.NJ tree based on genetic distance showed that 12 R. chinensis populations were divided into three groups.The first group include Hanzhong, Chenggu, Anxian, Emei, Zhushan and Shuifu populations, and Jinping and Malipo populations form the second group.Taijiang and Danzhai firstly clustered, and then together with Longsheng and Wufeng populations to form the third group.The results of Mantel test is consistant with cluster analysis, that is to say, there was no significant correlation between genetic distance and geographic distance within populations of R. chinensis.The study on population genetic diversity and genetic structure of R. chinensis with molecular marker techniques will provide basic data in molecular level for the further study of the co-evolution between R. chinensis and its parasitic aphid. Longsheng, Wufeng, Taijing populations with higher genetic diversity should be mainly conserved.