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The present investigation was carried out with 36 hybrids and they were evaluated for growth, quality, mosaic disease incidence and yield through line x tester method to identify combinations expressing high hybrid vigour in snake gourd. The significant variation in gca, sca and heterosis over the standard variety were noticed for all the traits. The line IC 308557 (L4), IC 284753 (L5), IC 546083 (L6) and the testers Jeyamkondam Local (T2) and Kulithalai Local (T1) were found to be best general combiners for growth, quality, mosaic disease incidence and yield characters. Among the hybrids L2xT3, L7xT2, L2xT4, L5xT1 and L8xT4 were found to be the good specific combiners (gca) for most of the characters viz., growth, ascorbic acid, mosaic disease incidence and yield per vine. Among the 36 hybrids, seven viz., IC333314 x Kumbakonam Local (L2xT3), IC433526 x Kulithalai Local (L3xT1), IC546083 x Kulithalai Local (L6xT1), IC546083 x Kumbakonam Local (L6xT3), IC433526 x Kumbakonam Local (L3xT3), IC284753 x Kulithalai Local (L5xT1) and IC410160 x Jeyamkondam Local (L7xT2) exhibited highly significant positive standard heterosis for growth, quality, mosaic disease incidence and yield. These seven hybrids were found to be suitable for exploiting heterosis. [ABSTRACT FROM AUTHOR]

A total of 50 hybrids was generated by Line x Tester mating design using ten lines and five testers of sweet corn. These hybrids along with parents and checks were evaluated at TNAU, Coimbatore during Kharif-2015. Genotypes were significantly different for all the traits under study. Green cob yield was found to have positive significant correlation with number of kernel rows per cob, plant height, green cob weight, total chlorophyll content, cob length, cob breadth, 100 seed weight, number of kernels per row indicating that indirect selection for yield through these traits will be effective. Green cob yield had no significant correlation with total sugar content of kernels indicating the scope of developing high yielding hybrids with high sugar content. Traits viz., tassel branching, green cob weight, number of kernels per row, green cob yield, 100 seed weight, reducing sugar, non reducing sugar, photosynthetic efficiency, stomatal conductance and total chlorophyll content recorded high genetic advance as per cent of mean coupled with high heritability thus providing maximum opportunity for improvement and genetic gain through selection of these traits. [ABSTRACT FROM AUTHOR]

The present study on heterosis and combining ability for seed yield and its components was carried out in a set of 15 F1 hybrids of sesame involving five lines and three testers diverse parents at Agricultural college, Bapatla. The ratio of the genetic variance was less than the unity, which indicated the predominance of the non-additive gene action in all the characters studied. The analysis revealed that none of the parents was found as good general combiners for all the traits consistently, however two lines YLM 95, IS 355 and a tester Gowri were found to be good combiners for seed yield and its contributing traits. The hybrids IS 355 x Gowri followed by KMR x Madhavi, YLM 95 x Gowri and IS 355 x Madhavi have exhibited higher heterosis (Average heterosis and Heterobeltiosis) for seed yield. These crosses involved good x poor and poor x poor combiner parents. Further improvement in seed yield could be possible through the hybridization and selection of transgressive segregants. [ABSTRACT FROM AUTHOR]