GENETIC CONTROL OF HUSKED NUT WEIGHT IN COCONUT (Cocos nucifera)

Abstract

The genetic control of husked nut weight in Coconut (Cocos nucifera) wasinvestigated using a full-diallel cross including eight parents. The parents were aselected sample of palms which gave an annual mean yield of 23 kg of copra perpalm with 713 gm of husked nut weight over five years. An average of fiveprogenies per cross planted in a fully randomised design were evaluated for fiveyears. Husked nut weight of five nuts per palm was recorded at each pick.Analysis of variance of mean husked nut weight confirmed the presence ofadditive and non additive genetic variance. The non additive genetic component wasfound to be higher in magnitude than the additive component. The heritabilityexpressed as the ratio of the genetic variance to the total phenotypic variance was0.45. Of the dominance components, directional dominance was non significant.Neither the presence of heterosis nor inbreeding depression was consistent among theselfed and crossed progenies elucidating the fact that not only crossing but selfingcould also improve the trait, depending on the genetic constitution of the individual.Reciprocal differences were evident in the crosses suggesting the importance of thedirection of cross.