Genetic variability and character association analysis of various quantitative traits of orchids (Dendrobium spp.) from the East Siang District of Arunachal Pradesh
D. Mahesh Reddy1,2*, Kalkame Ch. Momin3, V. Bhargav2, Nancy Lego4, P. Chakradhar1, V. Siva Teja5, Urati Mahesh6
1Department of Floriculture and Landscaping, Dr. YSRHU- College of Horticulture, Anantharajupeta, Andhra Pradesh- 516105, India. 2Department of Floriculture and Landscape Architecture, College of Horticulture and Forestry, CAU, Pasighat, Arunachal Pradesh, 791102, India. 3Department of Horticulture, North Eastern Hill University, Tura Campus, Tura, Meghalaya. 4All India Coordinated Research Project on Medicinal and Aromatic Plants and Betel Vines, College of Agriculture, CAU, Pasighat, Arunachal Pradesh, 791102, India. 5Department of Floriculture and Landscaping, KAU, Thrissur, 680656, India. 6Department of Plantation, Spices, Medicinal and Aromatic Crops, Dr. YSRHU- College of Horticulture, Andhra Pradesh- 516105, India. Corresponding author: Maheshduggireddy1@gmail.com
Abstract: To assess the genetic variability, heritability, and association of 21 key quantitative variables in 15 distinct Dendrobium species, efforts were made to improve the germplasm of Dendrobium orchids in different parts of Arunachal Pradesh between 2020 and 2022. Significant variance was found in every attribute in the study, indicating that there is sufficient genetic diversity to support breeding efforts. The most significant values of PCV and GCV were recorded for the number of flowers per inflorescence (136.13% and 135.35%, respectively) and the number of inflorescences per plant (136.18% and 133.94%, respectively). High heritability coupled with high genetic advance was observed for inflorescence length (99.74%), the number of flowers per inflorescence (99.68%), flower width in the front view (99.41%), and flower length (99.25%). Selection based on these characteristics would be more effective for improving interspecific hybrids. Other characters exhibited moderate broad-sense heritability with low genetic advance. Plant height, internode number, number of leaves, and flower longevity showed positive and highly significant associations with the number of flowers per inflorescence and the number of inflorescences per plant at both the genotypic and phenotypic levels. However, correlation study revealed that selecting parents based on plant height, internode number, number of leaves, and flower longevity in plants would be helpful in breeding programs.
