Krishan KumarVijay Kumar C. Talawade2024-06-202024-06-202023-06-09https://krishikosh.egranth.ac.in/handle/1/5810210647The present investigation comprising of 40 Tulsi (Ocimum spp.) genotypes received from ICAR- National Bureau of Plant Genetic Resources, New Delhi were grown in Randomized Block Design (RBD) with three replications in the Research Area of Medicinal, Aromatic and Potential Crops Section, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar during Kharif 2022. The observations were recorded for 10 qualitative and 17 quantitative traits. The 40 Tulsi genotypes were characterized into different categories for each of the qualitative trait. Analysis of variance revealed the presence of sufficient amount of genetic variability for all the 17 quantitative traits studied. The GCV and PCV estimates were high for dry herbage yield (47.31% and 47.74%), seed yield (47.21% and 48.17%) and number of spikes per plant (47.18% and 47.35%), respectively. High heritability coupled with high genetic advance was observed for number of spikes per plant, 1000 seed weight, fresh herbage yield, dry herbage yield and oil content. Seed yield per plant showed highly significant and positive correlation with number of spikes per plant (0.507** and 0.501**), 1000 seed weight (0.471** and 0.459**), number of flowers’ whorls per spike (0.455** and 0.396**), seedling length (0.291** and 0.264**) and fresh herbage yield per plant (0.262** and 0.257**) at both genotypic as well as phenotypic level, respectively. Path coefficients analysis revealed that the maximum positive direct effect was exhibited by seedling length (0.582) followed by 1000 seed weight (0.487), number of spikes per plant (0.371), number of primary branches per plant (0.292), fresh herbage yield per plant (0.292), seed vigour index-II (0.232) and number of flowers’ whorls per spike (0.209). The 40 Tulsi genotypes were grouped into 10 different clusters indicating the presence of genetic divergence among different genotypes. The maximum intra-cluster distance was recorded for cluster 7 and maximum inter-cluster distance was recorded between cluster 2 and cluster 10. Relative contribution of different traits towards genetic diversity revealed that 1000 seed weight (41.41%) contributed maximum towards genetic divergence followed by number of spikes per plant (17.31%), fresh herbage yield per plant (13.46%) and oil content (10.77%). Based on the maximum mean performance for seed yield, number of primary branches, fresh as well as dry herbage yield, oil content and seed vigour index-I & II, the genotypes EC 338772, EC 388890 and IC 326732 may be exploited in the breeding programmes to develop the improved cultivars of Tulsi for higher seed yield, oil content and other economically important traits.EnglishThesis