Abstract

                                An investigation was carried out to assess the nature and extent of heterosis for oil content and other economic traits in cotton (Gossypium hirsutum L.) through line x tester analysis. Among 40 hybrids analyzed, ten hybrids were expressed significantly positive heterosis for plant height, 15 hybrids for number of sympodia per plant, 16 hybrids for number of bolls per plant, 11 hybrids for number of seeds per boll, twenty hybrids for seed cotton yield and 14 hybrids for oil content over better parent. Four hybrids showed significantly negative heterosis over better parent for days to 50 per cent flowering which indicated earliness of flowering. The overall study of heterosis indicated that hybrid combinations viz., Sahana x LRA 5166 and L 604 x MCU 7 exhibited significantly positive heterosis for all the traits including oil content and seed cotton yield. Two hybrids namely Surabhi x LRA 5166 and CNH 36 x MCU 7 expressed significantly positive heterosis for all the characters included in the study except for days to 50 per cent flowering.

Key words : Cotton, heterosis, seed cotton yield, oil content.