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A line x tester analysis using six lines and eleven testers was carried out to study the combining ability and gene action for grain yield and 14 quantitative traits in pearl millet. Analysis of variance for combining ability revealed that significant differences among the mean squares was observed for lines, testers and lines x testers for all the characters except for mean squares due to lines for number of productive tillers per plant, ear head weight per plant, grain yield per plant, harvest index and threshing index and due to testers for ear head weight per plant, days to maturity, dry fodder yield per plant, grain yield per plant, harvest index and threshing index, which indicated the importance of both additive and non-additive genetic variances in the expression of these characters. The ratio of GCA variance and SCA variance indicated the predominance of non-additive gene action for the characters days to 50% flowering, length of protogyny, number of nodes per plant, plant height, number of productive tillers per plant, ear head weight per plant, days to maturity, 1000-grain weight, dry fodder yield per plant, grain yield per plant, harvest index and threshing index and additive gene action for ear head girth and ear head length. Among the lines, ICMA-04111, ICMA-92777 and ICMA-05333 and the testers J-2534, J-2454 and J-2507 displayed high gca effect for grain yield per plant and for some desirable traits. Significant and positive sca effect for grain yield per plant was displayed by the cross ICMA-05333 x J-2527 followed by ICMA-05333 x J-2340, JMSA-20064 x 283-SB-11, ICMA-92777 x STPT-115, ICMA-04999 x J-2539 and JMSA-20071 x J-2507. These crosses involved either average x average, good x poor, poor x poor or good x good general combining parents. These crosses have been identified as best hybrids for improving grain yield per plant and could be further evaluated to confirm their stable superior performance.

A line x tester analysis using 12 lines and three testers was carried out to study the combining ability and gene action in sesame for seed yield and 14 quantitative traits. Analysis of variance for combining ability revealed significant differences among the mean squares due to lines, testers and lines x testers for all the characters except oil content, which indicated the existence of genetic diversity among the parents and hybrids. General and specific combining ability variances showed the involvement of both type of gene actions in the inheritance of these characters. Among the lines, IC-81564, NIC-75, Borda-1 and among testers, G.Til-10 were good general combiners for seed yield per plant and some of its contributing traits. The cross combination, IC-81564 x G.Til-10 showed significant and positive sca effect for seed yield per plant and involved good x good combining parents. It was followed by AT-238 x G.Til-10, NIC-75 x G.Til-4, TNAU-12 x G.Til-4, Keriya-2 x G.Til-3 and Keriya-2 x G.Til-10 which involved either good x good, good x poor or poor x poor combining parents. These crosses have been identified as best hybrids for improving seed yield per plant and could be evaluated under different environment to confirm their superiority.

One hundred diverse genotypes of groundnut were evaluated for 15characters in order to construct selection indices. The characters, which had desirable correlation as well as moderate to high direct effect on pod yield per plant were considered as selection index criterion. The pod yield per plant (X1) along with its five components viz., days to maturity (X2), number of pods per plant (X3), kernel yield per plant (X4), biological yield per plant (X5) and harvest index (X6) were utilized for the construction of selection indices. The discriminant function had higher genetic gain and relative efficiency over straight selection for pod yield alone. The relative efficiencies of selection indices constructed in combinations of two or more characters were ranged from 105.90 to 536.06%, while genetic advance ranged from 12.75 to 64.58g. There was an increase in genetic gain and relative efficiency with inclusion of an additional trait in the character combination. A selection index consisting of pod yield per plant, days to maturity, number of pods per plant, kernel yield per plant and biological yield per plant and an index involving pod yield per plant, number of pods per plant, kernel yield per plant and biological yield per plant registered higher genetic gain and relative efficiency. These indices could be advantageously exploited in the groundnut breeding programmes for isolating high yielding genotypes.

A study was conducted in sesame to assess the extent of heterosis for fifteen quantitative traits including seed yield per plant. Twelve lines and three testers were crossed in a line x tester fashion to develop 48 F1 hybrids. The analysis of variance revealed highly significant differences among the parents and hybrids for all the characters, indicating the presence of sufficient amount of genetic diversity for all traits studied. Heterosis was worked-out over better parent and standard variety, G.Til-4. The standard heterosis for seed yield per plant ranged from -12.32 to 137.39 %. The crosses NIC-75 x G.Til-10, IC-81564 x G.Til-10, NIC-75 x G.Til-4, AT-238 x G.Til-10 and Borda-1 x G.Til-10 were good heterotic combinations for seed yield per plant, which recorded 137.39, 128.74, 111.34, 100.42 and 90.84 % standard heterosis, respectively. The heterosis for seed yield per plant was associated with the heterosis expressed by its component characters