HETEROSIS an‎d COMBINING ABILITY ESTIMATES FOR EAR TRAITS an‎d GRAIN YIELD IN MAIZE HYBRIDS

To increase maize yields, exploitation of heterosis has been proven as highlyeffective and is widely used over the world to produce new and improved hybrids. Present study was undertaken to estimate combining ability and heterosis in maize hybrid combinations for ear traits, plant height and leaf area. Five inbred parents were crossed in a diallel fashion excluding reciprocals and fifteen genotypes including 10 hybrid combinations and 5 parents were tested during summer 2013.Statistical analysis revealed significant difference for kernel rows ear-1(P≤0.05), and highly significant difference (P≤0.01) for days to silking, plant height, leaf area, kernels row-1, 1000-kernel weight and grain yield. Hybrid P3×P5and P3×P4was marked as suitable for breeding early maturing hybrids due to negative heterosis values. Highheterosis for plant height was recorded for P2×P3with significant SCA effects. P2in combination with P3, P4and P5showed significant SCA for greater leaf area,however,a significant positive heterosis was obtained only for P2×P3.Maximum numbers of kernel rowsear-1were countedin hybrid P3×P4;nevertheless, hybrid P1×P3 exhibitedthe highest MPH while P3×P4was the only combination to have significant BPH. Onthe other handP1×P4had the highest number of kernels row-1. The highest 1000-kernel weight was obtainedfor the hybrid P2×P3with highly significant heterosis and SCA.The grain yield remained highest in P2×P3(4719 kg/ha) followed by P4×P5(4616kg/ha) and P3×P4(4532 kg/ha). Hence the hybrid combination P2×P3was markedas superior for the development of high yielding hybrids among 10 hybrids tested considering its significant and positive SCA for yield related traits and highest grain yield.