Combining ability efects and heterosis estimates in maize (Zea mays L.)

Maize is becoming a crop of huge demand day by day due to its multiple uses but its productivity in farmer's felds is generally low due to lack of multiple resistant and wider adaptive improved maize hybrids. For development of improved maize hybrids, heterosis breeding has been recognized as most powerful breeding approach since long time. In this experiment, 54 single cross hybrids were evaluated along with their parental lines and two checks for combining ability and heterotic potential. Highly signifcant variations were observed within parents and hybrids which indicates a wide genetic variability for the studied characters and the possibility of genetic improvement through utilization of such genetic material of maize. The parents, L1 (D5–1), L6 (D49-2), L14 (D47-1), L17 (D36-1) and L18 (TSK92-3) exhibitted good GCA efects for grain yield and some of the yield contributing traits to emerge as valuable donor parents for further breeding programme. Based on SCA efect and standard heterosis, the hybrid combinations L5xT1 (D2-2xD47), L9xT3 (Azad Uttamx TSK32-1-1-3) and L8xT3 (D48xTSK32-1-1-3) were identifed as best for grain yield and some of the yield contributing traits.