Determination of genetic variation in Rhodiola crenulata from the Hengduan Mountains Region, China using inter-simple sequence repeats

Yidong Lei,Suhua Shi,Tashi Tsering,Hong Gao,Yang Zhong

doi:10.1590/s1415-47572006000200023

Abstract

The plant Rhodiola crenulata is a perennial herbaceous species distributed in the plateau region of southwestern China, especially the Hengduan Mountains region. It has been one of the most important traditional herbal remedies in Tibet for more than one thousand years, but the accelerated and uncontrolled collection of this plant since the 1980s has lead to deforestation. We used inter-simple sequence repeats (ISSR) to assess levels of genetic variation in R. crenulata from nine diverse natural populations in eastern Tibet and northern Yunnan, the first time such a study has been carried out. The 12 primers we used were able to detect 184 polymorphic loc. Analysis of molecular variance (AMOVA) indicated that species level genetic diversity was relatively high (p = 97.83%, and Ho = 0.464) and analysis using Shannons index showed that the within and between genetic diversity of R. crenulata are approximately equal. Neis genetic distance and unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis showed that the three populations from Tibet and the six populations from Yunnan form two major clusters. The Yunnan populations from three locations were further divided into three corresponding groups, indicating that genetic differentiation was correlated to geographic distribution. Understanding the genetic structure of R. crenulata provides insight for the conservation and management of this endangered species.

Highlights

The plant Rhodiola crenulata is a perennial herbaceous plant mainly distributed in the high plateau region of southwestern China, especially the Hengduan Mountains region including eastern Tibet, northern Yunnan and western Sichuan
This study is the first application of inter-simple sequence repeats (ISSR) markers to the assessment of genetic diversity in R. crenulata
The partition of genetic diversity using both Shannon’s index and Analysis of molecular variance (AMOVA) indicated that genetic diversity in R. crenulata is distributed within and between populations

Summary

Introduction

The plant Rhodiola crenulata is a perennial herbaceous plant mainly distributed in the high plateau region of southwestern China, especially the Hengduan Mountains region including eastern Tibet, northern Yunnan and western Sichuan. Thriving at high elevations (2800-5600 m) in cold, moist climatic areas of the Northern hemisphere near the tundra, R. crenulata grows exceptionally well in a variety of habitats including meadows, rocky crevices, cliffs and slopes, dunes and sandy soils. A cluster of R. crenulata plants often grows to several tens of square meters and produces reptant, succulent rhizomes and red extracting solutions from flowers, roots and stems (Fu and Fu, 1984; Wu and Raven, 2001). Recent pharmacological studies have found that this plant contains many ingredients such as salidrosides which are highly active against anoxia, fatigue, toxic reactions, radiation sickness, tumors and aging as well as presenting active-oxygen scavenging properties (Kurkin and Zapesochnaya, 1986; Peng et al, 1996; Ohsugi et al, 1999). Lei et al (2003, 2004) investigated the interpopulation chemical variability of essential oils from R. crenulata rhizomes from Tibet and Yunnan and found that there were two main chemotypes of the essential oils in Tibetan (geraniol-rich) and Yunnan (n-octanol- and geraniol-rich) R. crenulata populations which can be used for identifying the source of R. crenulata genetic resources

Methods

Results

Conclusion