Identification and Genetic Variation Analysis of Wild and Cultivated Germplasm of Angelica sinensis Based on cp DNA / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo conduct genetic variation analysis of 11 cultivars and 7 wild populations of Angelica sinensis in Gansu province based on the chloroplast gene （cp DNA）， and provide references for germplasm identification and breeding of new cultivars of A. sinensis. MethodThree pairs of cp DNA primers were used for polymerase chain reaction （PCR） amplification and sequencing of A. sinensis samples. MegaX was used to perform statistics on sequence characteristics and calculate mean genetic distances among A. sinensis populations. Unweighted pair-group method with arithmetic means （UPGMA） clustering tree based on genetic distance was constructed by NTSYS 2.10e. DanSP v6 was used to calculate sequence polymorphism and Tajima's D of A. sinensis. PERMUT was used to calculate the population structure of A. sinensis. Arlequin v3.5 was used to perform molecular variation analysis， and PopART1.7 was used to construct TCS haplotype network. ResultThree pairs of cp DNA primers were amplified， sequenced， compared， and combined to give a sequence length of 1 759 bp. One variable site was detected in the wild A. sinensis and 480 variable sites were detected in the cultivated A. sinensis， including 97 singleton variable sites， 383 parsimony informative sites， and 152 insertion-deletion sites. In the three regions of matK， psbA-trnH， and rbcL of cp DNA in the wild and cultivated A. sinensis， matK was the region with the highest polymorphism. Tajima’s D of all the combined sequences of A. sinensis were not significantly negative， but psbA-trnH and rbcL genes of the cultivated A. sinensis were significantly negative， indicating that the A. sinensis followed neutral evolution on a whole， while psbA-trnH and rbcL genes had undergone selection. The degree of genetic differentiation （Fst=0） among wild populations was lower than that among cultivated populations （Fst=0.114 19， P<0.05）. The degree of genetic differentiation between wild and cultivated A. sinensis was relatively high （Fst=0.942 55， P<0.01）. Genetic variation in the cultivated A. sinensis was mainly found within the populations （89%）. UPGMA cluster tree based on genetic distance showed that the wild A. sinensis and the cultivated A. sinensis were clustered into one branch， respectively， with a distant genetic relationship， and the population 3 in the cultivated A. sinensis was far from other cultivated populations. The TCS haplotype network consisted of 15 haplotypes and 4 unknown haplotypes， which was divided into 3 parts， with a large number of variations among each part. Shared haplotypes were only found in the wild or cultivated groups， and there were no shared haplotypes between groups. ConclusionThe genetic diversity of A. sinensis was low at species level， and the population diversity of the wild was lower than that of the cultivated. The degree of genetic differentiation between the wild and the cultivated A. sinensis was high， but that in the wild and the cultivated populations were low. Genetic variation in the cultivated A. sinensis was mainly found within populations.