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Low temperatures pose a major climatic problem for all rice growing countries as the rice crop growth and development requires optimum temperatures specific for each and every developmental stage. Thirty Five cold tolerant genotypes were evaluated under different dates of sowing for yield and yield related parameters, to identify high yielding genotypes suitable for late kharif and rabi seasons. Pooled analysis over environments shown highly significant mean squares due to G × E interaction for all the traits when tested against the pooled error, indicated that the genotypes interacted considerably with the environmental conditions that are associated with different dates of sowing. Significant environment linear component for all the characters indicating that the variation among the environments is linear and the linear response of genotypes to additive environmental variance. K-475, Himalaya-1, SKAU-82, Vivek Dhan -62 and Vivek Dhan -65 recorded favourable mean values for early flowering. MTU 1010 and RP-2421 are the stable genotypes for higher number of tillers. Twenty thee genotypes were found for panicle exertion, which is an important trait that influences yield under cold stress. Vivek Dhan- 62, V L Dhan -207, V L Dhan -208, SKAU-339, RP-2421 and Rajendra are the stable genotypes with panicle length more than 20 cm. Spikelet fertility ranged between 70-87% in twenty five genotypes which recorded non significant deviation from regression. V L Dhan -206, SKAU-382, HPR-2373, Vivek Dhan -85, Sukaradhan-1, V L Dhan -207, Vivek Dhan -65, SKAU-389 and V L Dhan -208 registered their adaptability to wider environments for filled grains per panicle. For seed yield per plant, V L Dhan-209, V L Dhan-208, Sukaradhan-1, Vivek Dhan -65 and Himalaya-1 were considered as ideal genotypes for all seasons. Among the stable genotypes for seed yield per plant, Sukaradhan-1, Vivek Dhan -65 and Himalaya-1 showed stability for important yield contributing characters viz; days to 50% flowering, tillers per plant, panicle length, panicle exertion, spikelet fertility and filled grains per panicle.

Information on combining ability and standard heterosis are crucial for the success of any hybrid breeding program. The present study was conducted in sweet corn involving crossing of twenty inbreds as female lines and five inbreds as testers in line × tester mating fashion during kharif, 2019. Resulted 100 F1 s were evaluated in rabi, 2019-2020 for twelve yields and its attributing traits. Analysis of variance for combining ability revealed the existence of wider variability in the material studied exhibiting significant differences due to lines, testers, hybrids and various interactions. Non-additive gene action was observed pre-dominant for all the traits. Inbreds SCGP-88, SCGP-111, SCGP-36-3- 1, SCGP-91, BSL-4, SCGP-44-2, VNR-SC-24, VNR-SC-23, SCGP-66-1 and SCGP-61-1-4 were identified as good general combiners. Crosses viz., SCGP-207-1 × SCGP-44-2, SCGP-54 × VNR-SC-29, SCGP-42 × SCGP-80, SCGP-82 × SCGP-80 and SCGP-66-1 × SCGP-44-2 were identified as promising hybrid combinations based on per se performance, sca effects and standard heterosis over the commercial checks. [ABSTRACT FROM AUTHOR]

Low temperature tolerance during seedling stage is an important yield contributing attribute for rabi/boro rice. Thirty five cold tolerant genotypes along with three checks were evaluated for the stability of seedling traits under four cold environments viz., controlled conditions at 80C, 130C & at 280C under field condition during Rabi season. The Genotype x Environment interaction was significant for all the characters which indicates differential behavior of genotypes in different cold environments. More pronounced linearity over non linearity for all the characters revealed the possibility of precise prediction of performance of genotypes over the cold environments. None of the genotypes showed average adaptability over all the cold regimes for shoot length. For root length, performance of all the genotypes was entirely unpredictable as they recorded significant non linearity. Among the genotypes, Vivek Dhan -85 and V L Dhan-86 were found to be stable for both vigour index and speed of germination. K-429 was highly suitable for poor environments for the traits viz; shoot length, root length and speed of germination. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate genetic and epistatic effects governing the inheritance of seed cotton yield and yield components using the four crosses viz., CPD 420 x LK 861, CPD 420 x 4084, NA 1325 x LK 861 and NA 1325 x 4084 and their F2, parents and back cross generations for seven characters. Estimates of gene effects through joint scaling test of three, six parameter and sequential fit model revealed that simple additive dominance model exhibited lack of good fit for all the traits indicating the role of non-allelic interactions. Differential model schemes for same trait in different crosses were noticed in the present investigation which was due to different parents involved with variable gene frequency with opposing and reinforcing gene effects. The magnitude of [d] was relatively small to that of other gene effects indicating its minor role in the inheritance of these traits. All the traits exhibited the three types of epistatic interactions viz., add x add (i), add x dom (j) and dom x dom and duplicate type of interaction in one or other cross and none of the traits showed complementary type of interaction. Linkage or higher order interactions were also observed in all the crosses which were evidenced by the significance of all the tested parameters and χ2 value. [ABSTRACT FROM AUTHOR]