Genetic diversity and population structure in <i>Meconopsis quintuplinervia</i> (Papaveraceae)

Abstract

Meconopsis quintuplinervia is regarded as a valuable medicinal plant in Tibetan medicinal system. This species is distributed in Qinghai, Xizang, Sichuan, Shanxi ,Gansu and Hubei provinces of the People's Republic of China. Genetic variation of 16 M. quintuplinervia populations sampled from Qinghai and Gansu of China was examined by random amplified polymorphic DNA markers (RAPDs). In total, 225 scored DNA bands were amplified from the 17 primers used. Of the 225 loci, 192(85.33%) were
polymorphic, and total genetic diversity (Ht) was 0.2954 and Shannon’s information index (I) was0.4371, suggesting a relatively high rate of genetic variation at the species level. The average within-population
diversity also appeared to be high, with PPB, He and I values of 70.50%, 0.2408 and 0.3347, respectively. Analysis of molecular variance (AMOVA) revealed 78.3% of variation within populations and only 21.7% between populations. Nei’s coefficient of differentiation (GST) was found to be high (0.2320), also confirming the relatively high level of genetic differentiation within populations. By UPGMA cluster analysis, based on Nei’s standard genetic distance, the populations were divided into three groups including the populations distributed in same location together in every  group. The results exhibit a strong genetic differentiation which is obviously due to genetic drift in the isolated populations. The genetic structure of M. quintuplinervia has probably been shaped by its breeding modes, biogeographic history and human impact (both grazing and collection for medicinal purposes). This research might be an efficient way to conserve genetic resources of the medicinal plant, in addition to its effective uses.