Genetic improvement of fibre traits in diploid cotton (G. herbaceum L.) through interspecific hybridization using G. barbadense tetraploid species

Abstract

Diploid cotton Gossypium herbaceum has wide adaptability and high degree of resistance to biotic and abiotic stresses. Development of diploid cotton varieties suitable for 40s count yarn will make them more remunerative to diploid cotton growers. In this regard a study on genetic introgression through inter-specific hybridization was initiated using G. barbadense tetraploid cotton to improve fiber strength of G. herbaceum cotton. Pedigree selection from F2 to F11 was practiced. These F11 lines were evaluated at ARS, Dharwad Farm, during 2009-10 in Augmented Design-II. Observations on fiber traits, seed cotton yield and ginning outturn were recorded and analysed using Windostat version 8.5. Seed cotton yield ranged from 801 to 3037 kg/ha with 832.38 per cent GCV, 100 per cent heritability and 42.71 per cent genetic advance as per cent mean. Range for ginning outturn was 20.70 to 42.50 per cent with 25 per cent heritability, 13.93 per cent GCV and 18.84 per cent genetic advance as per cent mean. Recorded fibre strength was in the range of 15.42 to 20.67 g/tex with variability parameters like 10.36 per cent GCV, 86 per cent heritability and 5.98 per cent genetic advance as per cent mean. The value for 2.5 % span length ranged from 23.87 to 29.52 mm with 9.38 per cent GCV, 72 per cent heritability and 5.24 per cent genetic advance as per cent mean. The seven selections PSCCOL-15, 30, 31, 32, 36, 53 and 62 recorded significantly higher seed cotton yield than DLSa-17 (1124 kg/ha) and superior fiber traits than DDhC-11 (17.10 g/tex, 24.00 mm) commercial diploid cotton varieties. These selections recorded 49 to 125 per cent yield increase over DLSa-17. It indicates the possibility of improvement in both seed cotton yield and fibre quality traits of G. herbaceum cotton through inter-specific hybridization using tetraploid cotton G. barbadense as a donor parent.