Forty nine genotypes of wheat were studied for generating scientific information on nature and magnitude of genetic variability and diversity for designing breeding programme. The experiment was conducted in randomized complete block design in three replications. The data were recorded on days to 50% flowering, plant height, peduncle length, number of productive tillers per plant, days to maturity, spike length, number of spikelets per spike, number of grains per spike, 1000-grain weight, biological yield per plant, grain yield per plant, harvest index and gluten content. Analysis of variance revealed significant differences among the genotypes for all the characters under study. The highest estimates of phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were observed for grain yield per plant. High heritability coupled with high genetic advance was observed for grain yield per plant. Based on D 2 -Statistics, 49 genotypes were grouped into eight clusters. The highest inter-cluster distance was found between cluster VII and VIII followed by III and VII. This indicates that genotypes included in these clusters possess wide genetic diversity. Grain yield per plant (31.46%) showed highest contribution towards genetic divergence; therefore, this character was major determinant of genetic diversity. On the basis of divergence and cluster mean it may be suggested that maximum heterosis and good recombinants could be obtained in crosses between genotypes of cluster VIII, VII and III in varietal improvement programme. Thus, crosses between the genetically diverse genotypes of cluster VIII with genotypes HUW 655, HP 1937, DBW 88 and HD 3058 and cluster VII with genotypes like HP 1938, HUW 656, K1006, DBW83, DBW 84, K1004, UP2822 and NW5050 are expected to exhibit high heterosis and are also likely to produce new recombinants with desired traits.

Forty nine genotypes of wheat were evaluated for 12 quantitative and one quality traits during 2010-11. The experiment was conducted in randomized complete block design with three replications at Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. The mean, range, genotypic and phenotypic coefficient of variation, heritability in broad sense, genetic advance, correlation and path analysis were analyzed. Plant height, number of productive tillers per plant, spike length, 1000 grain weight, biological yield per plant and harvest index were significant and positive correlated with grain yield per plant. The phenotypic and genotypic path coefficients exhibited high positive direct contribution of number of productive tillers per plant, plant height, harvest index and 1000 grain weight towards grain yield.The positive indirect effect of plant height on grain yield was registered via days to maturity, number of spikelets per spike, 1000 grain weight and biological yield per plant. Number of productive tillers per plant revealed contribution on grain yield via number of grains per spike, 1000 grain weight, biological yield per plant and harvest index revealing that indirect selection of these characters would be effective in improving grain yield per plant. Higher genotypic coefficient of variance along with high heritability and genetic advance for grain yield per plant, plant height, number of spikelets per spike, number of grains per spike and 1000 grain weight would also be of great use for indirect selection for improvement in yield per plant.

A study on genetic variability, heritability and genetic advance for seed yield and component traits was made in 40 genotypes of riceduring kharif 2011-2012 at SHIATS, Allahabad. The analysis of variance showed highly significant differences among the treatments for all the 13 traits under study.The genotypes namely CN 1446-5-8-17-1-MLD4 and CR 2706 recorded highest mean performance for panicles per hill and grain yield. The highest genotypic and phenotypic variances (VG and VP) were recorded for spikelets per panicle (3595.78 and 3642.41) followed by biological yield (355.72 and 360.62) and plant height (231.48 and 234.35).High heritability (broad sense) coupled with high genetic advance was observed for plant height, flag leaf length, panicles per hill, tillers per hill, days to maturity, spikelet’s per panicle, biological yield, harvest index, 1000 grain weight and grain yield, indicating that selection will be effective based on these traits because they were under the influence of additive and additive x additive type of gene action. Highest coefficient of variation (PCV and GCV) was recorded for tillers per hill (18.42% and 17.23%), panicle per hill (19.76 % and 18.68%), spikelet’s per panicle (34.30 and34.07 %), biological yield (28.31 % and 28.12 %), 1000 grain weight (15.57 % and 15 31 %) and grain yield (46.66% and 23.54 %), indicating that these traits are under the major influence of genetic control, therefore the above mentioned traits contributed maximum to higher grain yield compared to other traits, indicating grain yield improvement through the associated traits.

The present study aimed to assess the genetic architecture of rice through various biometrical techniques and this was achieved through a field experiment conducted during the Kharif 2022 season utilizing 23 distinct genotypes of rice. The trial was performed at the field experimentation center, Department of genetics and plant breeding, School of agriculture, Lovely Professional University. The research concluded that the highest genotypic and phenotypic coefficients of variation were for the number of productive tillers per plant, grain L/B ratio and grain yield per plant. Additionally, high heritability was observed for all traits except for kernel breadth. The investigation also explains high genetic advance as a percent of the mean for all traits except spikelet fertility and kernel breadth. Grain yield per plant had a significant positive genotypic correlation with the number of productive tillers per plant, filled grains per panicle, and total number of grains. Path analysis revealed that kernel L/B ratio, kernel length, filled grains per panicle, total number of grains, and number of productive tillers per plant had the maximum positive direct effects. The study suggests that selection based on these traits could be more effective in improving rice yield. The germplasms falling in different clusters with high mean for grain yield and other component characters can be utilized for hybridization programme to obtain elite segregants.