Yanal ahmad Alkuddsi , M.R. Gururaja Rao , S.S. Patil , T.H. Gowda , Mukund Joshi

1. Department of Genetics and Plant Breeding, University of Agricultural Sciences, Dharwad, Karnataka, India
2. Department of Genetics and Plant Breeding, University of Agricultural Sciences, Bangalore, Karnataka, India
3. Head of Agricultural Research Station, Bavikere, Therikere
4. Department of Agronomy, University of Agricultural Sciences, Bangalore
Author    Correspondence author
Genomics and Applied Biology, 2013, Vol. 4, No. 5   doi: 10.5376/gab.2013.04.0005
Received: 30 Jun., 2013    Accepted: 16 Jul., 2013    Published: 01 Dec., 2013

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Alkuddsi et al., 2013, Combining Ability Analysis for Seed Cotton Yield (Kapas Yield) and Its Components in Intra Hirsutum Hybrids and Forming Heterotic Boxes for Exploitation in Cotton, Genomics and Applied Biology, Vol.4, No.5 35-49 (doi: 10.5376/gab.2013.04.0005)

An investigation was carried out during kharif 2008 in cotton (G. hirsutum L.) to evaluate intrahirsutum hybrids produced through Line x Tester mating design using 6 hirsutum non Bt lines (RAH 318, RAH 243, RAH 128, RAH 146, RAH 97 and RAH 124) and 8 hirsutum non Bt testers ( SC 14, SC 18, SC 7, SC 68, RGR 32, RGR 24, RGR 58 and RGR 37) to generate information on combining ability effects in respect of kapas yield (seed cotton yield) and yield attributing characters and to for heterotic boxes. The 48 F₁ hybrids were sown in a randomized complete block design (RCBD) with two replications at the Agricultural Research Station, Bavikere, UAS, Bangalore. From the estimates of additive and dominance variance, it is observed that dominance variance was predominant for all the characters and was maximum for kapas yield per plant followed by plant height and bolls per plant. However, both additive and dominance variance were found to be important in case of ginning per cent, monopodia per plant, mean boll weight, days to 50 per cent flowering, seed index and lint index. Among the lines, the mean sum of squares was significant for all characters except monopodia per plant and mean boll weight. The testers differed significantly for most of the characters except monopodia per plant, mean boll weight and seed index. However, the line x tester interaction was significant for all the characters except monopodia per plant, mean boll weight, seed index and lint index. Estimation of gca effects of lines and testers indicated that, no single line or tester was found to be a good general combiner for all the characters studied. However, the line RAH 146 exhibited significant gca effects in the desired direction for 5 characters (plant height, sympodia per plant, bolls per plant, kapas yield and ginning per cent) and was considered as best general combiner among lines. Among the testers, the tester RGR 32 was considered as the good general combiners, since it had high significant gca effects in the desirable direction for monopodia per plan, bolls per plant, mean boll weight and ginning per cent. The hybrid RAH 128 x RGR 37 exhibited significant specific combining ability for plant height, sympodia per plant and kapas yield; RAH 146 x SC14 for monopodia per plant, bolls per plant and kappa yield. The estimates of overall gca status of parents indicated that, the lines RAH 318, RAH 243 and RAH 124 were good general combiner as evident from its high (H) overall gca status. Among testers, testers SC 14, SC 7, SC 68 and RGR 24 were identified as good combiners with high (H) overall gca status. It also becomes important to determine whether a cross is a good specific combination across all the traits or not for the same reason, it is evident that 23 out of 48 hybrids had high (H) overall sca status, while remaining 25 crosses had low (L) overall sca status across all the traits studied.

Line x tester analysis; General combining ability; Specific combining ability; Gossypium hirsutum L.