Metroglyph Analysis in Coconut (<i>Cocos nucifera</i> L.)

Abstract

Metroglyph analysis was done in a group of 23 genotypes of coconut, Cocos nucifera L. The varieties came under two groups based on morphological characters. Three groups were recognized when the classification was made on the basis of nut cha racters. The exotic cultivars, in general, had relatively higher expression for morpholo gical and nut characters. The possibility of obtaining heterotic hybrids from divergent parental combinations was indicated. MATERIALS AND METHODS Twenty three genotypes of coconut (Cocos nucifera L.) maintained at the Coconut Research Station, Veppankulam, Tamil Nadu, India, formed the materials for the study. The trees in different accessions were in the age group of 24-26 years. The ex periment was raised in a completely randomised design. Among the 23 cultivars, 14 were collected from India and the rest exotic. The exotic types were drawn from Malay sia (three) Philippiness, Java, Siam, Fiji, New Guinea and Vietnam (Cochin China) through Central Plantation Crops Research Institute, Kasaragod, India. Although the number of palms in each genotype varies from 6 to 13, observations were limited to only 4 palms in each genotype which resemble to each other very closely in morphology and nut charac ters, to avoid intra genotypic variation. The mean data over the four palms were subjected to study. Observations were made on six morphological traits viz. plant height, number of functional leaves, girth at collar, length of petiole, length of leaflet bearing portion and the number of leaflets on one side, during 1982 to 1984. For studying the nut components, two nuts of 12 months maturity were collected from each of the four trees at harvest. Data were collected on weight of whole nut, dehusked nut, kernel and copra per nut and kernel thickness for each nut separately by following standard procedures during the summer months (March, April, May, June), The mean data over 96 observations (2 nuts, 4 palms, four months and three years) in each variety were used for the study.