Botany, origin and genetic resources of coconut

Abstract

The coconut palm, Cocos nucifera L., native of the humid tropics, is a versatile, multipurpose palm with slender unbranched stem crowned with a cluster of long green pinnate leaves producing fruit bunches borne on the leaf axils. The stem lacks bark, cambium, and with no secondary growth features, volume once formed remains unaltered. Similarly, the fibrous roots never expand in thickness after formation. The palm neither produces branches nor forms vegetative buds on the stem, the only vegetative buds being those at the apex of the stem and if this bud gets killed, the palm dies. The palm is non-tillering and monoecious, the spadix bears distinct male and female flowers and the fruits take about 10-12 months to mature. C. nucifera, though a monotypic species with no known wild/domesticated relatives, still presents considerable intraspecific diversity and heterozygosity. Systematic classification of the genetic diversity in the crop, using the distinct morphological features of the palm, has been attempted by many. The genetic resources in this crop are conserved mainly in field gene banks, in the coconut-growing countries. Various aspects covering botany, morphology, phylogeny, development, varieties, their classification, the variability reported and the genetic resources in the crop are discussed.