Genetic diversity of vetiver isolates (Chrysopogon zizanioides/nigritanus) available in South Africa based on ITS, ndhF and rbcL sequencing analyses

Abstract

Vetiver grass (Chrysopogon zizanioides (L.) Roberty) is sterile and only regenerates vegetatively from clumps of the rootstock. Together with its vigorous and deep root system this makes it ideal for use in soil remediation and erosion control. In South Africa, Hydromulch (Pty) Ltd is part of the landscape, soil reclamation and erosion control industry. The company uses vetiver grass on awide scale and has compiled a collection of isolates to serve as possible germ lines for industrial use. Due to the different approaches in environmental management as well as environmental factors, a variety of ecotypes form during the planting, adaptation and domestication of this genus. Chrysopogon nigritanus ((Benth.) Veldkamp, 1999), is a close relative native to Africa and differs morphologically only slightly from C. zizanioides. It may seed freely and thus use of this species should be avoided. The need arose to screen other non-fertile plants to uncover additional genotypic variety to enable diversification of vetiver plantings. The aim of this study is to characterise the genotype of 19 isolates of vetiver obtained from Hydromulch (Pty) Ltd via sequencing analyses of three DNA fragments, ITS, ndhF and rbcL. According to the results generated during this study very little or no genotypical differences exist amongst the different isolates available from the Hydromulch (Pty) Ltd plant collection. Only in the case of the ITS inference were differences observed between 3 isolates