Studies on combining ability and heterosis involving diverse cytoplasmic male sterility system in pearl millet

Abstract

Investigation was undertaken to study the combining ability and to quantify the magnitude of heterosis of alloplasmic isonuclear lines of pearl millet. The results revealed that the lines with A4 cytoplasm are significantly better general combiner for grain yield per ear, ear weight, ear length and productive tillers per plant than the lines with A1 and A5 cytoplasm. Pollinators IP-1497, IP-973, IP- 872 and IP-10085 proved their utility for breeding high yielding hybrids. None of the pollinators proved to be good combiners simultaneously for all the traits. Majority of the hybrids carrying A4 cytoplasm were highly heterotic for the traits viz., days to maturity, plant height, ear head weight, grain yield/ear, grain yield /plant and ear length. On the other hand, majority of the A5 based hybrids were highly heterotic for productive tillers, ear length, flag leaf area and peduncle length. The mean as well as range of heterosis for days to flowering, days to maturity, plant height, flag leaf area and 1000-grain weight was limited in all the three sources of cytoplasm. The magnitude of heterosis was high for ear weight, grain yield/ear and grain yield/plant and A4 based hybrids had maximum heterosis for grain yield per plant and other panicle components, followed by A1 and A5 indicating a distinct advantage of these cytoplasms.