TOP CROSS ANALYSIS FOR HETEROSIS AND COMBINING ABILITY IN FORAGE PEARL MILLET (PENNISETUM GLAUCUM L.)
RAHUL KAPOOR* AND PARDEEP SINGH
Department of Plant Breeding &
Genetics Punjab Agricultural University,
Ludhiana (Punjab), India
*(e-mail : rahulkapoor@pau.edu)
(Received : 29 July 2017; Accepted : 23 August 2017)
SUMMARY
A set of 15 CMS lines was top crossed to four populations as testers to obtain 60 top cross hybrids. The hybrids were evaluated for general combining ability (gca), specific combining ability (sca) and heterosis. The mean squares due to parents differed significantly for all the characters, thus indicating the presence of variability in the parent material for all the 16 traits. The variances due to gca and sca were significant. The computed variance ratio (σ2sca/σ2gca) revealed the predominance of non-additive gene action in the inheritance of quality traits. The perusal of the estimates of general and specific combining ability variances indicated the preponderance of non-additive gene action in the inheritance of all the traits. For GFY, five CMS lines 01777A (5.36), 543A (5.03), 92222A (4.70), 315A (3.03) and 111A (1.78) and two testers viz., RBC-2 (0.79) and Giant Bajra (0.64) were good general combiners with highly significant positive gca effects. The hybrids 315A × RBC-2, 543A × GFB-1, 01777A × Giant Bajra, 92222A × GFB-1 and 408A × Giant Bajra topped the list of crosses for forage yield. This high yielding ability was contributed by significant values of traits viz., plant height, number of tillers per plant and leaf area index.
Key words: Combining ability, environments, forage, heterosis, hybrids, pearl millet, quality