Ratooning and Combining Ability Analysis through Line x Tester Mating Design in Interspecific Cotton Hybrids (G.hirsutum x G, barbadense)

摘要

Cotton (Gossypium spp.) is an important fibre crop and plays a vital role as a cash crop in commerce of many countries in the world. The development of cotton hybrids which can offer the great yields and quality fibre is the current research in cottonbreeding. For the first time, here we investigated the mean performance and ratooning ability of thirty novel cotton hybrids. In addition, we also analyzed the expression of general combining ability (GCA) of the parents and specific combining ability (SCA) of hybrids in order to develop high yielding and better quality cotton cultivars in both first crop and ratoon crop. L x T analysis revealed that the significant GCA and SCA effects for all the studied traits. The significant range of variability was observed in all the traits except for boll weight and elongation percentage in parents and hybrids. Based on mean performance, the evaluated hybrids varied significantly (p < 0.05) in first crop and ratoon crop for the all studied traits. The predominance of additive gene action was estimated for the number of bolls per plant and fibre bundle strength in first crop which were found to be controlled by additive gene action due to high GCA variance. In ratoon crop, the predominance of dominant gene action was estimated for all the studied traits which were found to be controlled by non-additive gene action due to high SCA variance. Among the parents, TCH 1819 was found to be a good combiner for all the investigated traits except for boll weight. The hybrids, MCU 13 x SUVIN and TCH 1819 x TCB 209 were found to be the best specific combinations for fibre bundle strength.