Comparison of genetic diversity in Pogostemon cablin from China revealed by RAPD, morphological and chemical analyses

Abstract

The genetic diversity of 16 patchouli populations by random amplified polymorphic DNA (RAPD), morphology and chemical composition was presented in this paper. Polymorphism of RAPD primers and the percentage of polymorphic bands revealed with RAPD were 79.21 and 78.40%, respectively, which indicated a high level of genetic diversity existed among Pogostemon cablin (Blanco) populations. A dendrogram based on RAPD analysis showed most populations from the same or adjacent regions were classified together. High polymorphism in morphological parameters was found among populations, but did not reflect completely the differences by geographic location. According to the relative contents of nine compounds in P. cablin, the tested samples were divided into two main clusters, pogostone-type and patchouliol-type. A correlation between genetic and chemical polymorphism (r2 = 0.816) was higher than that between genetic and morphological variations (r2 = 0.629). High morphological and chemical variability as well as genotypic polymorphism provided ecological advantages that might explain the extensive distribution of P. cablin.   Key words: Pogostemon cablin (Blanco) Benth, genetic diversity, random amplified polymorphic DNA (RAPD), morphology, essential oil.