Genetical Studies in Papaya (Carica papaya L.)

Genetical studies in papaya were carried out using the variety Coorg Honey Dew. The purification programme in the variety Coorg Honey Dew was taken up and the data were recorded from the S2 to S4 generation of sibmated progenies. The variety Coorg Honey Dew yields big sized fruits of about 1.5-2.0 kg, pulp is yellow in colour and fruits are sweet to taste with a TSS of 12°Brix. The sibmated progenies were studied for uniformity in fruit size and shape. A total of ten half-sib families (25 trees/family)were used for the study. Genotypic variation and phenotypic variation was highest in S2 generation, while in S4 variation it was observed to be low. The PV and GV were observed to decline with the progress of the generation. The genotypic coefficient of variation was lesser than the phenotypic coefficient of variation implying the role of environment influencing the characters. High heritability was recorded for all the characters except inter nodal length and pulp thickness. Very little difference was noticed in the heritability values between S3 to S4 generation. Among the characters, high genetic advance as percent mean was recorded for the characters of fruit weight, fruit length and number of seeds, while other characters exhibit moderate to low. Heritability and genetic advance as percent mean was obtained high for the characters of fruit weight and fruit length. The correlation studies showed that plant height at first fruiting were positively correlated with fruit length and first flowering height. The study indicated that three generation of sibmating considerably reduced the variability in morphological and yield characters.