Diversity analysis and establishment of core collection among Akebia trifoliata (Thunb.) Koidz. in Qinba mountain area of China using ISSR and SRAP markers

摘要

Akebia trifoliata (Thunb.) Koidz. is a perennial woody liana that belongs to Akebia Decne. Being high-value medicinal and economic crops, different parts of the plants are utilized for producing medicines, fruit, tea, wine, edible oil, etc. A. trifoliata is mainly wild, slow growth and low reproduction. However, the fragmented habitats caused by increasingly human activities led to a sharp decline yield of wild resources. Therefore, the domestication and cultivation of this plant could be the solution. Study on the genetic diversity among individuals or populations are the basis of making its conservation strategies and germplasm selection. In this study, 242 A. trifoliata accessions of 12 populations, collected from Qinba mountain area of China, were assessed using ISSR and SRAP markers, which generated 99.4% and 98.7% polymorphism, respectively. Both ISSR and SRAP revealed the high level of genetic diversity (H = 0.31, I = 0.47, ISSR; H = 0.33, I = 0.50, SRAP), and also revealed high genetic differentiation (Gst = 0.36 for ISSR, Gst = 0.34 for SRAP) and gene flow (Nm = 1.76 for ISSR, Nm = 1.44 for SRAP). Genetic variation observed within population was higher than of among population. The Mantel Test showed that the genetic variation among populations could be explained by the geographical distances (r(2) = 0.1797, p = 0.020, ISSR marker; r(2) = 0.2793, p = 0.010, SRAP marker;) The results of Structure analysis and PCoA also supported clustering model. Finally, based on ISSR and SRAP data, a core collection of 56 accessions by the LDSS method was selected. Collectively, our results lay the foundation for making A. trifoliata's conservation strategies and germplasm selection.