Variability in seed traits, oil content and genetic diversity in local and exotic accessions of <i>Jatropha curcas</i> L. in Senegal

Abstract

Variability in seed traits, oil content and genetic diversity of Jatropha curcas L. according to rainfall gradient in Senegal are hereby reported and discussed. Seed oil variability ranged from 58.61% in Sudanian zone to 46.94% in Sahelian zone. Seed oil content and seed thickness were correlated to rainfall with a correlation coefficient of 0.62 and 0.48 respectively. However, seed length, breadth and 20 seed-weight were not correlated to rainfall. The random amplification of polymorphic DNA (RAPD) primers used to assess genetic variation showed a clear polymorphism. The mean polymorphism rate was 42.68%. A low variability was observed in the accessions. The genetic diversity was not correlated to geographic position. On the basis of coefficient similarity values, the accessions were genetically diverse. Cluster analysis based on similarity values classified Jatropha curcas L. accessions into three major clusters of which cluster I was the largest group. The lowest genetic distance (0.029) was recorded between Karang and Kaffrine accessions whereas the highest genetic distance (0.274) was observed between Bignona and Karang accessions. Accession from Bignona recorded the highest intra-population variation. Special attention must be accorded to accessions with high oil content, seed weight and high intra-population variation for future selection programs.

Keywords: Jatropha curcas L., seed size, oil content, genetic diversity, Senegal.

African Journal of Biotechnology Vol. 12(34), pp. 5267-5277