[Genetic diversity and genetic differentiation of Rhododendron concinnum wild populations in Qinling Mountains of Northwest China: an AFLP analysis]

Abstract

By using amplified fragment length polymorphism (AFLP) technique, an investigation was made on the genetic diversity and genetic differentiation of seven wild populations of Rhododendron concinnum in Qinling Mountains of Northwest China. A total of 182 amplification products were generated from three AFLP selective primer combinations, of which, 151 were polymorphic. The percentage of polymorphism was 83.1%. The change trends showed by the percentage of polymorphic loci (PPL), Nei's gene diversity (h), and Shannon's information index (I) were uniform, and the order of the populations was Meixian > Zhashui > Zhen' an > Huxian > Ningqiang > Nanzheng > Zhouzhi. The POPGENE analysis showed that the R. concinnum had higher genetic diversity at both species level (PPL = 91.22%, I = 0.7217, h = 0.5095) and population level (PPL = 77.56%, I = 0.6409, h = 0.4725). The coefficient of gene differentiation among the populations (Gst) was 0.0726, indicating that 92.74% of genetic variation occurred within the populations. The analysis of molecular variance (AMOVA) showed that 85.3% of the genetic variation was within the populations, and 14.7% of it was among the populations. The unweighted pair group method with arithmeticmean (UPGMA) indicated that there was no significant correlation between the genetic distance and the geographic distance among the R. concinnum populations. The conservation strategies for R. concinnum germplasm resources were put forward.