Isozyme variation among teak (Tectona grandis L.f.) provenances.

Fourteen enzyme systems were analysed in leaf parenchyma of nine native and introduced populations of teak. These enzyme systems were encoded by 20 putative loci of which 18 were polymorphic. Populations showed a general lack of heterozygosity (average FIS = 0.11). On average over the 18 polymorphic loci, the genetic differentiation among provenances varied according to the estimator: 0.09 for GST, 0.12 for FST and 0.19 for δ. The cluster analysis showed two main gene pools, the first consisted of the Indian provenances and the second of African, Indonesian and Thai provenances. Genetic distances among populations of the same group were similar, and lower than the genetic distances between populations from different groups. The factorial analysis on genotypes of seedlings also showed the same geographic differentiation into two major groups. The possible natural distribution of teak in Java is discussed.