Analysis of coconut (Cocos nucifera L.) diversity using microsatellite markers with emphasis on management and utilisation of genetic resources

Sixteen SSR markers were used to identify genetic relationships of 43 coconut accessions conserved ex-situ in field gene banks of the Coconut Research Institute of Sri Lanka (CRISL). The 16 SSR markers clearly unveiled the genetic relationships of Sri Lankan coconut populations. Gene diversity and polymorphism information content (PIC) were relatively higher in the common ‘tall’ coconut and Pacific tall coconut than in autogamous dwarf form of coconut. The SSR assessment unveiled the genetic lineages based on evolutionary mechanisms signifying the narrow genetic base of coconut germplasm, with most of the diversity confining to ‘tall’ coconut. The main genetically different coconut groups identified were ‘tall’, ‘San Ramon and alike’ and ‘dwarf’. These have already been utilised in coconut improvement programmes and the study emphasizes the need for enrichment of the gene pool by exotic introductions. The overall results also supports the hypothesis that coconut disseminated from it’s center/s of origin in far east to Indo Atlantic regions via America.

Keywords: Coconut, genetic diversity, germplasm, microsatellite

doi :10.4038/jnsfsr.v37i2.1065

J.Natn.Sci.Foundation Sri Lanka 2009 37 (2):99-109