Genetic Structure and Conservation of Teak (Tectona Grandis) Plantations in Côte d'Ivoire, Revealed by Site Specific Recombinase (SSR)

Abstract

Teak (Tectona grandis L.f; Verbenaceae) is a diploid species (2n=36). It is native to the tropical deciduous forests of India, Myanmar, Thailand and Laos. Snuffed for its aesthetic physical properties and its qualities, teak is becoming increasingly important in the forest plantation development in Côte d'Ivoire. To preserve the genetic resources of this species and ensure the supply of genetically superior quality germplasm for improvement and plantations, a core collection of superior genotypes with large genetic diversity is a prerequisite. This paper reports the use of site-specific recombinase (SSR) technology using microsatellite DNA markers to investigate the level of genetic variability, distribution of genetic variation and genetic relatedness in Tectona grandis grown in Côte d'Ivoire. The proportion of the total genetic variation resides within provenances (80.52 %) with 5.5 % of the variation occurring among populations of one region and 13.98 % among regions. The SSR markers showed a clear differentiation of the populations introduced in Côte d'Ivoire with an Fst = 0.21. The populations coming from the natural area were characterized by three clusters corresponding to South India, North India and Thailand. The study on the origin of African teak was close to North of India. However, Bambuku 7 population was an exception, as it seemed to have some affinity with Thailand populations. The use of SSR markers for conservation of teak forest diversity is discussed.