BETTINA HEIDER, ELKE FISCHER, TANJA BERNDL, RAINER SCHULTZE-KRAFT
University of Hohenheim, Institute of Plant Production and Agroecology in the Tropics and Subtropics, Department of Biodiversity and Landrehabilitation, Germany
Pueraria montana (LOUR.) MERR. (kudzu) is a neglected crop with a long history of cultivation and ethnobotanical uses in Asia. Its potential as forage and soil cover crop as well as its close relation to soybean has stimulated research aiming at conservation of germplasm, plant improvement, and breeding programmes. Nevertheless, little is known about genetic diversity of this species. However, such information is key to efficient collection, sustainable utilisation, and appropriate conservation strategies of plant genetic resources. The objective of this study was to develop an appropriate molecular marker based methodology to analyse the genetic variation of five P. montana accessions collected in Bac Kan province, North Vietnam, in order to gain a basic understanding of genetic differentiation patterns in the target region. Using RAPD markers, P. montana presented a high level of variation with 54.3% of the detected markers being polymorphic and a mean JS coefficient that amounted to 0.35. The UPGMA dendrogram showed that P. montana accessions clustered in congruence with their eco-geographical origin i.e. genetic diversity increased with geographic distance or coincided with topographically isolated collecting sites. The high level of differentiation among P. montana accessions suggested that variation was mainly distributed among accessions rather than within accessions. Thus further collections should take place at larger distances or in diverse environments where isolation by distance or by natural barriers can be expected, and in addition, should focus on sampling small numbers of individuals from many different populations rather than intensive collecting of only few populations. The results of this study indicate that the RAPD technology is highly informative and thus represents an effective tool to generate molecular markers in P. montana. Generated data serve as a reference point for further collecting and research on this species.
Keywords: Genetic diversity, kudzu, molecular markers, North Vietnam, plant genetic resources conservation, Pueraria montana