Studies on genetic diversityin snake gourd (trichosanthesanguina l.)

An investigation entitled “Genetic divesityin snake gourd (Trichosanthesanguina L.)” was carried out in the Department of Horticulture, Faculty of Agriculture, Annamalai University, Tamil Nadu, India during 2004. The parents from diversified genotypes in snake gourd were evaluated for fruit yield per plant, yield attributing characters and quality traits with the objective of selecting superior genotypes for heterosis breeding. The characters observed were days to first male and female flower opening, number of fruits per plant, fruit length, fruit girth, flesh thickness, single fruit weight, fruit yield per plant, number of seeds per fruit, Vitamin C and acidity content of fruit. The degree of divergence among 40 genotypes was computed using D2 analysis. The results revealed that the genotype G27 followed by G2, G29, G5 and G12 expressed the maximum fruit yield per plant. High PCV, GCV and genetic advance as per cent of mean were observed among the genotypes for most of the traits studied except days to first male flower opening and acidity content of fruit. Among the 40 genotypes studied, the genotypes were grouped into eight clusters. Among 40 diversed genotypes, the cluster I consists the maximum number of 23 genotypes. The traits namely single fruit weight, fruit length, number of fruits per plant, number of seeds per fruit and fruit girth contributed more to the fruit yield per plant. Based on the per se performance with specific trait and genetic divergence from different clusters, six genotypes namely P1–Hessaraghatta local (Bangalore, Karnataka), P2–Ottanchathiram local (Dindigul district, Tamil Nadu), P3–IC-212484, NBPGR, Trichur, P4–Michaelpalayam local (Dindigul district, Tamil Nadu), P5–PKM–1 (mutant variety, HC&RI, TNAU, Periyakulam), P6–Vellayani local (Kerala) were selected for crossing in full diallel programme.