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Cotton is vital in economic, political and social affairs of most countries of the world including India. There is increasing demand of cotton in local and international market, hence urgent need to exploit potential of available germplasm through hybridization and selection programme. Thorough study of F2 populations may highlight proper knowledge for the design of different breeding programmes. This study was on F2 generation of the cross ARBC1301 x Surabhi along with their parents. Observation was made on 230 F2 progenies and 15 randomly selected plants for parents. Sixteen biometric observations; days to flowering (DF), plant height (PH), number of monopodia per plant (NMPP), number of sympodia per plant (NSPP), number of nodes per plant (NNPP), first internode length (FIL), number of fruiting points per plant (NFPP), number of bolls per plant (NBPP), boll weight (BW), ginning outturn (GO), single plant yield (SPY), 2.5% span length (SL), bundle strength (BS), uniformity ratio (UR), fibre fineness (FF) and elongation percentage (EP) were recorded. Single plant yield ranged from 6.17g to 97.04g for the F2 with a mean of 33.64. F2 hybrids were earliest to flower, they also recorded the least in plant height, first internode length, boll weight, 2.5% span length, uniformity ratio, elongation percent, fibre fineness and single plant yield. However, in number of nodes per plant, number of fruiting points per plant, number of sypodial branches per plant and number of bolls per plant, F2 hybrids performed better than either of the parents. The parents ARBC1301 and Surabhi recorded 33.97 and 36.13 for mean of single plant yield respectively. Principal component analysis revealed that number of bolls per plant, number of fruiting point per plant, number of sympodia per plant contributed more variation and can be considered as major traits for selection while handling a large population. Step wise regression showed that number of sympodia per plant, number of bolls per plant and boll weight were major predictor for single plant yield. Leaf anatomical parameters study indicated that the progeny #197 has highest thickness of spongy parenchyma (25.14μ) and highest palisade cell height (16.02μ) which indicated its tolerance to the sucking pest Leaf hopper.

Key words: Cotton, Variability, Correlation, Regression, Selection