Assessment of Genetic Diversity for Growth and Yield Traits in Marigold (Tagetes Spp.L)

Abstract

The present investigation was carried out at the Horticulture Research Center, College of Horticulture, SVPUA&T during 2023-24 to study the diversity studies in marigold (Tagetes spp.). The experiment was laid out in Randomized Block Design with three replications. Eighteen genotypes of marigold were evaluated for fourteen vegetative, flowering and yield related traits to study the genetic parameters such variability, heritability, coefficient of variation, correlation and path coefficient analysis. Analysis of variance for all the traits showed significant differences among genotypes. High range in mean performance was observed for plant height (23.82- 43.34 cm), number of primary branches per plant (7.71-26.44), number of secondary branches plant (24.44-61.23), days taken to first bud initiation (39.37-58.34 days), days taken to first flower initiation (49.67-66.67 days), flower diameter (4.55-8.44 cm), fresh flower weight (2.89-8.93 g), number of flowers per plant (53.23-153.45), flower yield per plant (224.05-860.32 g) and shelf life of flower (2.02-4.01 days). High heritability was observed for dry flower weight (97.40%), flower yield per plant (95.46%), number of flower per plant (94.31%) and number of branches per plant (93.11%). High Values of genetic advance as per cent of mean was recorded for dry flower weight (120.90%), fresh flower weight (72.98%), flower yield per plant (72.49%) and number of flowers per plant (61.69%). The magnitude of correlation coefficient at genotypic level was found higher than the corresponding correlation at phenotypic level. Flower yield per plant had a positive and highly significant correlation both at genotypic and phenotypic levels with flower diameter (0.757), fresh flower weight (0.752), dry flower weight (0.669), shelf life of flower (0.615) and plant height (0.584). Path coefficient analysis revealed that fresh flower weight (2.066) expressed highest positive direct effect on flower yield per plant followed by number of secondary branches per plant (1.013), days to taken first bud initiation (0.646), leaf length (0.485), number of flower per plant (0.389) and shelf life of flower (0.115). The clustering pattern based on Mahalanobis D2 statistic indicated the existence of wide genetic divergence among genotypes for various traits studied and categorized the genotypes into five distinct clusters. The highest inter-cluster distance was observed between cluster-IV and cluster-III 164.05 and 122.48, respectively