991 Environment & Ecology 32 (3) : 991—994, July—September 2014 Website: environmentandecology.com ISSN 0970-0420 Genetic Diversity Analysis in Upland Cotton (Gossypium hirsutum L.) Santoshkumar Pujer, S. S. Siwach, Jagadeesh Deshmukh, R. S. Sangwan, O. Sangwan Received 29 January 2014; Accepted 27 February 2014; Published online 11 March 2014 Abstract An experiment was conducted during kharif of 2011 and 2012 to assess the pattern of mor- phological variation through D 2 technique in 68 cot- ton genotypes (Gossipium hirsutum L.). Based on this technique genetic variability was evaluated for 9 characters viz., days to first flower, plant height (cm), number of monopods per plant, number of bolls per plant, boll weight (g), seed index (g), lint index (g), ginning out turn (%) and seed cotton yield per plant. All genotypes were grouped into 5 distinct clusters, which differed among themselves, C II had the larg- est genotypes (29) followed by group III having 26 genotypes, Group I consisted of 11 genotypes and C IV and V consist of only one genotypes. Based on the inter-cluster distances, C IV and C V were found to be most divergent followed by C III and C IV, C III and C V, C I and C V and II and C V could be used as parents representing wide genetic variability helpful in future hybridization breeding programme for achieving higher seed cotton yield. Keywords Genetic diversity, D 2 statistic, Gossypium hirsutum L, Seed cotton yield, Cluster. S. Pujer*, S. S. Siwach, J. Deshmukh, R. S. Sangwan, O. Sangwan Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar 125004, India e-mail : pujer_851@rediffmail.com *Correspondence Introduction Cotton is the most important fiber and cash crop. It is fulfilling the domestic need as well as earning foreign exchange for the country. The genus Gossypium be- longs to the family. Malvaceae is divided into four species viz, Gossypium arboreum, G. herbaceum, G.. hirsutum and G. barbadense. The species, G. hirsutum largely cultivated in India. Ninety per cent of world cultivated cotton is under this species. Germplasm have high level of genetic diversity which provides a basic material for launching a crop improve- ment programme. Genetic diversity is the basic re- quirement in any crop improvement programme. The hybrids involving the parents with high diversity among them are expected to exhibit higher amount of heterotic expression and broad spectrum of variabil- ity in segregating generation. Multivariate analysis, utilizing Mahalanobis’s D 2 statistics has been found Table 1. Percentage contribution of each trait toward diver- gence (Tocher method). Sl. Time ranked Contribution No. Characters first (%) 1. Days to first flower 522 22.92% 2. Plant height (cm) 319 14.00% 3. Number of monopods/plant 355 15.59% 4. Number of bolls/plant 329 14.44% 5. Boll weight (g) 220 9.66% 6. Seed index (g) 108 4.74% 7. Lint index (g) 43 1.89% 8. Ginning out turn (%) 21 0.92% 9. Seed cotton yield/plant (g) 361 15.83%