Sri Lanka yellow semi tall; a new addition to the coconut (Cocos nucifera L.) classification in Sri Lanka

Abstract

In Sri Lanka, coconut (Cocos nucifera L.) has been classified into three varieties, typica, nana and aurantiaca based mainly on their stature and breeding behaviour. Typica and nana are tall and dwarf coconuts respectively while aurantiaca includes intermediate types. Different phenotypes within a variety have been classified as forms of coconut. Current Sri Lankan coconut classification includes 19 different forms within three varieties. There are four different forms of coconut within variety nana, as green, yellow, red and brown dwarfs based on the colour of the epicarp of the fruit. They all conform to the morphological features of variety nana except the yellow dwarf population which was observed to be a phenotypic mixture of different types of coconut. The current study was conducted to differentiate the phenotypes within the Sri Lankan Yellow Dwarf (SLYD) population and to classify them based on existing criteria. A sample of 200 yellow dwarf palms were studied to determine their breeding behaviour, and the morphological characteristics related to stem, leaf, inflorescence and fruit morphology and yield. Based on quantitative and qualitative data generated, the pure Sri Lanka yellow dwarf coconut form could be distinguished and in addition a new coconut form which was named as Sri Lanka Yellow Semi Tall (SLYST) which was classified within the variety aurantiaca, was identified within the yellow dwarf population. There was a further group of coconuts which could not be placed within the existing varietal classification and they were hypothesized to be a population resulting from cross pollination between SLYD and SLYST.