SSR markers indicate a common origin of self-pollinating dwarf coconut in South-East Asia under domestication

- Dwarf coconut originated from a typical domestication event in Southeast Asia.
- The triggering event was the appearance of autogamy which, after a few generations, resulted in fixed lines each incorporating a random subset of the alleles of the ancestral Tall population.
- The presence of the bole character and the height in coconut depend on different major genes.

The commercial cultivation of dwarf coconut is rare in the world, representing about 5% of global population. However, Dwarfs are currently receiving more attention, particularly for the harvest of tender nut water. Dwarfs are distinguished from tall coconuts primarily by their short height with an absence of a bole at the base of the stem, their early setting of nuts, their predominantly self fertilizing mating system and by large numbers of relatively small nuts. To date, the origin and domestication of Dwarfs has not been established. This study investigates the origin and domestication of dwarf coconut using molecular markers, mainly microsatellite (SSR) data. The inheritance of height and the presence of a bole was investigated in the F2 of a cross between Dwarf and Tall palms. The data suggest that the presence of a bole results from a single codominant locus. There was no strong association between the presence of a bole and height, with height also depending on a single codominant gene. However genetic and environmental factors make it difficult to assign individuals a definite genotype. SSR allele frequency differences between dwarf and tall accessions, ethno botanical and geographic information indicate that dwarf coconut originated from a typical domestication event in Southeast Asia.