Early generation testing for specific combining ability and heterotic effects in maize variety Sarhad white
Specific combining ability and heterotic effects for grain yield, flowering and morphological traits in maize variety Sarhad white analysed through Line x Tester mating design using 25 S2 lines and two testers during kharif and rabi crop seasons of 2008-09. Observations were recorded on days to 50% flowering, plant height, ear height and grain yield. Among 50 evaluated testcrosses viz., 173 x Jalal, 192-1 x Jalal, 231-1 x Jalal, 237-1 x Jalal, 46-1 x Kiramat, 65-1 x Kiramat, 91-3 x Kiramat, 119-1 x Kiramat, 126-1 x Kiramat, and 195-1 x Kiramat, were identified as good specific combiners for grain yield. These hybrids could be utilized in maize heterosis breeding to exploit hybrid vigor. Significant negative heterosis over mid parent of flowering traits was exhibited for TC- 12-2, TC- 77-2, TC- 79-2, TC- 91-3, TC- 119- 1, TC- 122-2, 126-1 and TC- 231-1. Maximum mid parent heterosis was detected for Kiramat crossed with SW 128-1 and SW-197-2 for plant height and ear height, respectively. Significant positive heterosis over mid parent of grain yield was found for TC- 12-2, TC- 77-2, TC- 151-1, TC- 220-1 and TC- 222-1. Significant negative heterosis over better parent of flowering traits was exhibited for all the testcrosses. Better parent heterosis for plant height ranged from -1.63 to 46.00%, while for ear height better parent heterosis varied from -20.53 to 14.21%. Significant positive heterosis over better parent of grain yield was showed for most of the testcrosses. Thus these crosses possess high heterosis which could be exploited commercially for higher yield in maize.