RESUMEN
Objective: The genetic diversity and population structure of Gynostemma pentaphyllun were investigated to give the rise to theoretical foundation for its resources protection and rational utilization. Methods: Six pairs of SSR primers were screened in 28 natural populations of 426 individuals to calculate the genetic parameters of G. pentaphyllun, and further then cluster analysis was carried out. Results: The genetic diversity of G. pentaphyllun was low: the average value of the percentage of polymorphic loci (PPL) and Nei's genetic diversity index (He) was 58.33% and 0.18, respectively. The values of Shannon index (I) within different populations were ranged from 0.02 to 0.50. AMOVA revealed that genetic variation mainly existed among the populations (inter-populations was 78.86%, intra-populations was 21.14%). Furthermore, it possessed the significant population genetic differentiation (FST=0.673) with low level of gene flow (Nm=0.142). The outcomes of cluster analysis indicated there were distinct genetic relationships and genetic structures within different ploidys of G. pentaphyllun. Conclusion: The populations of G. pentaphyllun exist a low level of genetic diversity and clear genetic structure. We suggest that it is necessary to employ in-situ conservation for the natural populations of G. pentaphyllun with higher genetic diversity, while for the populations which contain specific genotypes, it is better to combine ex-situ conservation with in-situ conservation in protection.
RESUMEN
Objective: To analyze the genetic diversities and phylogenetic relationships of Gynostemma pentaphyllun germplasm. Methods: Genetic diversities and phylogenetic relationships of 48 G. pentaphyllun germplasm from 12 provinces in different ecological environments were analyzed by inter simple sequence repeat (ISSR) molecular makers. Results: (1) Fifteen primers were selected from 100 primers which had clear and stable polymorphic bands. A total of 214 loci were obtained, including 206 loci, on average, amplification site of each primer 14.27 and polymorphic loci (PPL) was 96.26%. The averagely observed number of alleles (Na), effective number of alleles (Ne), Shannon information index (I) and Nei's genetic index (H) were 1.9626, 1.3358, 0.2211, and 0.3598, respectively. The enetic similarity coefficient (GS) ranged from 0.57 to 0.96. Cluster annlysis with UPGMA method showed that the 48 testing materials were divided into four groups at the level GS 0.72. Conclusion: The results of ISSR analysis reveal that G. pentaphyllun germplasm has a higher genetic diversity level and the genetic relationship is not entirely consistent with geographical distribution and ecological environment.