An investigation into impact of heterosis and inbreeding depression on fibre quality and oil content of allotetraploid cotton (Gossypium hirsutum L.)

In the present study, a total of four direct and diverse experimental crosses and their F2 were assessed according to the CFBD design kharif 2022-23 at Main Cotton Research Station, NAU, Navsari to estimate the heterosis, heterobeltiosis and inbreeding depression for fibre quality parameters and oil content in tetraploid cotton. For the fibre length, the cross III exhibited highest significant positive heterosis (11.36 %) and heterobeltiosis (11.18 %); for the fibre fineness, the cross I exhibited highest negative significant heterosis (-12.87 %) and heterobeltiosis (-3.26 %); for the fibre strength, the cross IV exhibited highest significant positive heterosis (4.59 %) and the cross II exhibited highest significant positive heterobeltiosis (1.30 %); for oil content the cross IV exhibited highest significant positive heterosis (18.27 %) and heterobeltiosis (14.40 %). Besides these, the highest inbreeding depression for the trait viz., fibre length, fibre fineness, fibre strength and oil content were recorded by the cross III (22.11 %), cross IV (-4.43 %), cross IV (12.89 %) and cross I (18.37 %), respectively.