Genetic diversity of Phyllanthus emblica populations in dry-hot valleys in Yunnan
云南干热河谷地区余甘子居群的遗传多样性研究

Phyllanthus emblica(Euphorbiaceae)is one of the dominant species distributed in dry-hot valleys of southwestern China.Besides its function in ecology,environment and reforestation,it is also an important medicinal plant.We studied the genetic diversity in four populations of P.emblica sampled from dry-hot valleys of Yunnan using ISSR(inter-simple sequence repeats)markers.Based on 12 primers,135 clear and reproducible DNA fragments were generated,of which 115 were polymorphic,accounting for 85.19%.The coefficient of genetic differentiation(GST)equaled 0.1222.Such a high level of genetic diversity and low level of population genetic differentiation might result from the breeding system of this species.There was a lack of significant association between genetic and geographical distances(r=0.19798,P=0.6513>0.05)among P.emblica populations.The results suggest some important recommendations about sampling meth-ods to be used in ecological reforestation of dry-hot river valleys.