pubscirivista.org Journal of Ecology Environment & Biology 2014;2(1):83-92 HETEROSIS FOR FIBER CHARACTERS, SEED COTTON YIELD AND ITS ATTRIBUTES IN INTRA AND INTER-SPECIFIC HYBRIDS OF COTTON (GOSSYPIUM SPS.) S. RAJAMANI*, M. GOPINATH, K.H.P. REDDY Regl. Agril. Res. Station, Lam, Guntur 522034, A.P, INDIA. Corresponding Author: E mail: mani_breeder@rediffmail.com Received on: 16/11/2013 Revised on: 21/11/2013 Accepted on: 31/12/2013 Key words – Cotton Inter-Specific Crosses Heterosis Heterobeltiosis ABSTRACT A study was conducted in cotton with six parents crossed in half diallel fashion and their F 1 s (15) were crossed with other parents (4) to produce 60 three way crosses to assess the extent of heterosis over mid and better parents for seed cotton yield and fibre characters. Single cross hybrids were found superior to three way crosses in expression of significant relative heterosis for number of bolls per plant, boll weight, seed cotton yield, seed index and lint index, where as three way crosses shown for ginning outturn, 2.5% span length and bundle strength. Positive and significant heterobeltiosis were recorded for number of bolls, seed cotton yield per plant and seed index in single cross hybrids than three way cross hybrids except in lint index. INTRODUCTION The lint-bearing species of the genus Gossypium, the true cottons, are four, out of which the diploid (2n = 26) species G. arboreum and G. herbaceum are indigenous in Asia and Africa. The history of introduction into India of the new world cottons (tetraploid species of G. hirsutum and G. barbadense with 2n = 52) dates back to the 18 th century AD. India had gained a pride place in the global cotton statistics with the largest cropped area of 12.19 million ha in 2011-12, growing the most diverse cultivars in terms of botanical species and composition, producing the widest range of cotton fiber quality suitable for spinning 6’s to 120’s counts yarn, and supporting the largest agro-based national industry of the country. Cotton (Gossypium hirstum L.) is one of the important commercial crops of the world and among the fibre crops it is considered as the king. India is the second largest producer in the world with 371 lakh bales and productivity of 481 kg lint per ha and forms the backbone of Indian Textile Industry. In Andhra Pradesh cotton is being grown in an area of 18.54 lakh hectares with a production and productivity of 54.50 lakh bales and 499.7 kg lint per ha respectively. The present study was carried out to study the heterotic potential in the single and three-way crosses and to exploit the extent of heterosis for commercial exploitation of hybrid vigour. MATERIAL AND METHODS The experiments were conducted at Regional Agricultural Research Station Lam, Guntur, Andhra Pradesh located at an altitude of 31.5m above MSL. Geographically this location is at latitude of 16 0 2’N and longitude of 80 0 3’E. The soils are black cotton type with clay texture. Six diverse cotton cultivars viz , 241-4-2(1), G Cot 100(2), RFS 3438(3), 65-2(s)-3(4), Hyps 152(4) G hirsutum genotypes and Suvin (6) G barbadense genotype were selected as basic material for the study. Hybridization programme for generating breeding material during Kharif 2009 six parents viz , 241-4-2, G Cot 100, RF 53438, 65-2 (s)-3, Hyps 152 ( G hirsutum ) and Suvin ( G barbadense ). Recommended package of practices were adopter Journal home page: http://pubscirivista.org/new1.aspx JOURNAL OF ECOLOGY, ENVIRONMENT & BIOLOGY Rajamani S, et al: Heterosis for Fiber Characters, Seed Cotton Yield and its Attributes in Intra and Inter-specific Hybrids of Cotton (Gossypium Sps. )