Genetic Variability and Correlation Studies in I Papaya (Carica Papaya L.)

Abstract

The present investigation entitled, "Genetic variability and correlation studies in Papaya (Carica papaya L. )" involving 17 genotypes/cultivars was undertaken to study the genetic variability, heritability, genetic advance, correlation coefficient and path coefficient analysis. The cultivars/ genotypes were tested in randomized block design with 3 replications. The characters under study were flower initiation, first flowering, plant height, number of leaves, days taken to harvesting, plant height, stem girth, number of leaves, length of petiole, first fruiting height, number of fruits per plant, fruit yield per plant, fruit weight, fruit length, fruit girth, pulp thickness, breadth of central cavity and total soluble solids. The analysis of variance revealed significant differences among the genotypes for all the characters. Plant height ranged from 120 to 185.33 em. Pusa Nanha was found to be of minimum plant height (120.00cm) while Pusa Giant of maximum plant height. Flower initiation took 212.93 to 228.83 days. Pusa Nanha attained the minimum duration for flower initiation while, Pusa Giant was found to be maximum. Flowering (days) ranged from 230.83 to 242.27. The minimum TSS was recorded in Pusa Nanha while the maximum was in Pant Papaya 1. Number of fruits per plant ranged from 19.67 to 60.73. The cultivar Pusa Nanha bore minimum number of fruits per plant while Surya the maximum (60. 73). Fruit weight ranged from 906.90 to 1558.77 g. Fruits of cultivar Surya weighed lowest fruit weight; while, Pusa Giant the highest. The fruit yield per plant ranged from 24.87 to 70.33 kg. Pusa Nanha recorded minimum fruit yield per plant (24.87kg) while it was the maximum (70.33kg) in genotype Papaya P S 1. High heritability (in broad sense) estimates were obtained for plant height at flowering (99.70%), fruit weight (97.50%), flower initiation (94.80%) fruit per plant (96.40%), fruit yield per plant (93.50%), petiole length (93.30%), fruit girth (92.40%), days to flowering (91. 70%) and plant height (86.70%). High genetic advance was noticed in plant height at flowering (46.96) followed by fruits per plant (43.32), fruit yield per plant (36.89). Genotypic coefficients of correlation of plant height highly significant and positive with flower initiation (0.731**), plant height at flowering (0.640 .. ), fruit length (0.577**), number of leaves at flowering (0.492**), fruit girth (0.474**), central cavity (0.458**) and TSS (0.747**) while, significant and positive with petiole length (0.377*), plant girth (0.388*), pulp thickness (0.388*) and non-significant and positive with flowering at days (0.333), number of fruits per plant (0.296) and fruit weight (0.160). Under path coefficient analysis the plant height had the negative direct effect on fruit yield per plant and plant height via fruit weight, number of fruits per plant, fruit girth, plant height at flowering and days to flowering contributed positive indirect effects where as plant height via TSS, pulp thickness, central cavity, fruit length, number of leaves at flowering, plant girth, petiole length and flower initiation had contributed negative indirect effects. The plants of genotype PS 1 yielded more fruits of superior quality. Yield and quality are the most important economic traits in papaya and ther for this enotype can be recommended for release.