MSc

The present investigation on “Development and evaluation of hybrids in ivy gourd (Coccinia grandis L.Viogt.) was carried out at the College of Agriculture, Vellayani during 2007-2008. The objectives of the study were to develop hybrids in ivy gourd, to estimate genetic parameters, variability among and within families and to identify superior hybrids over the check variety “Sulabha”.
Hybridization was carried out between four selected gynoecious and three androecious lines. Based on the mean values of the twelve families and their progenies variability among the families and progenies were studied. Genetic parameters and standard heterosis were also estimated in this study.
The family 1(Royappanpatty 1 x Royappanatty local) revealed superiority over the other families for days to flower, first harvest, length, girth number of fruits and fruit yield per plant.
The magnitude of variation among the progenies of 12 families revealed the heterogeneous nature of the F1 families. Significant variation among the progenies for vitamin C content was expressed in eight families viz., family 3, 4, 5, 7, 9, 11 and 12. Seven families viz., family 2, 3, 4, 5, 6, 11 and 12 showed significant variations among progenies for days to first flowering. Variations among progenies for fruit length were expressed by the families 2, 3, 4, 6, 9, 10, and 11. The families 4, 5, 8 and 10 showed significant variations for average fruit girth among the progenies. The families 4, 5 and 7 showed variations among progenies for days to first fruit harvest. The families 2, 6 and 8 showed variations among the progenies for girth of fruits. Families 4, 6 and 11 recorded significant variations among the progenies for number of fruits. Families 4 and 6 showed significant variations among progenies for fruit yield per plant. Superior plants can be selected from the families showing significant variation for different characters.
Pooled analysis of the data showed significant differences among the progenies for all the characters. The minimum days to flowering was recorded in progeny 1 and 5 of family 1 (Royappanpatty 1 x Royappanatty local) followed by progeny 7 of the same family and progeny 1 of family 3. (Royappanpatty 1 x Karyavattam). The same trend was observed for days to first harvest of fruits. The progeny 1 of family 1 was found to be earliest to take harvest followed by three other progenies progeny 2, 5 and 6 of the same family.
Significant variation for average fruit length was observed among the progenies. Progeny 1 of family 1 recorded the longest fruits. The highest fruit girth was observed in progeny 1 of family 4. The progeny 3 of family 3 produced fruits having the maximum weight followed by progeny 3 of family 1. The maximum number of fruits was produced by progeny 4 of family 1. Progeny 1 of family 4 recorded the highest vitamin C content. The highest fruit yield was recorded by progeny 3 of family 1 followed by progeny 1 of family 3 and progeny 3 of the same family. Superior progenies identified for different characters from the hybrid population can be utilized for further improvement.
The results of the analysis of variance showed significant differences among the genotypes for all the characters studied.
The differences between phenotypic and genotypic coefficients of variation were found to be low in this study indicating the major contribution of genetic component.
The highest heritability was estimated for days to first harvest followed by fruit yield per plant, fruit weight, fruit length, fruit girth, number of fruits per plant, days to first flower and vitamin c content. High heritability and high genetic advance estimated for important traits like fruit yield per plant, number of fruits per plant, and fruit weight which indicated the effectiveness of selection.
Higher genotypic correlation than the phenotypic correlation observed for most of the characters indicated the reduced influence of environment. The number of fruits per plant had significant positive correlation with yield per plant, fruit length and fruit weight. Average length of fruits, girth of fruits, average weight of fruits and number of fruits per plant exerted significant positive direct effect on fruit yield per plant. Therefore improvement of anyone of these characters would bring out simultaneous improvement of yield.
The families showed standard heterosis at varying levels for different characters. In this study mean values of the families were taken for comparison with the standard parent. Compared to the standard check “Sulabha” the hybrid population took more days to flower. However, among the hybrid progenies family 1 took the minimum days to flower and fruit harvest. The families 1 (Royappanpatty 1 x Royappanatty local) and 3 (Royappanpatty 1 x Karyavattam) manifested marginal positive heterosis for fruit length and families 1 (Royappanpatty 1 x Royappanatty local), 2 (Royappanpatty 1 x Vellayani local), 3 (Royappanpatty 1 x Karyavattam) 5 (NBPGR 1 x Vellayani local and) and 6 (NBPGR x Karyavattam) expressed heterosis for fruit girth. The positive heterosis for average fruit weight was observed in the families 1 and 3.
The maximum positive heterosis for number of fruits per plant was observed in the family 1 followed by 2 and 3. Nine hybrids expressed positive heterosis for vitamin C content. The heterosis for fruit yield per plant was the maximum in family 1 followed by 3 and 2. The superior progenies identified for different characters from the hybrid population can be utilized for further improvement.







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