Genetic variation and heterotic effects for seed oil, seed protein and yield attributing traits in upland cotton (Gossypium hirsutum L.)

An investigation was carried out to assess the expression of per se performance and heterotic effect for seed oil, seed protein besides various yield attributing characters studied from 28 hybrids involving four adapted varieties as lines and the seven testers in line x tester analysis. A wide range of variability was observed for seed oil content in the parents and their 28 hybrids. The seed oil content in parents ranged from 17.0 to 22.1%, and hybrids varied from 17.7 to 22.9%.The hybrid, MCU 12 x SOCC 11 exhibited significant positive heterotic effect and per se performance for boll weight. The hybrid MCU 5 x SOCC 17 had high per se performance and positive significant heterotic effect for seed protein with seed cotton yield. Two hybrids showed high heterotic effect and per se performance for seed protein content. The hybrid MCU 12 x SOCC 17 exhibited higher per se performance and heterotic effect for seed cotton yield along with seed oil content and MCU 5 x SOCC 17 recorded more seed protein combined with seed cotton yield. Four hybrids revealed greater per se performance and positive heterosis for seed oil content. Of these, Surabhi x TCH 1646 exhibiting highest per se performance, heterotic effect was found to be best for directional selection. Key words: Cotton, heterosis, seed oil, seed protein, yield.