COMBINING ABILITY STUDIES FOR SOME YIELD CONTRIBUTING TRAITS OF BREAD WHEAT UNDER NORMAL AND LATE SOWING CONDITIONS

A 7 × 7 diallel analysis involving seven wheat genotypes was conducted under normal and late sowing conditions to determine the combining ability of these genotypes for yield related traits i.e. plant height, tillers per plant, spikelets per spike, grains per spike, 1000-grain weight and grain yield per plant. Preponderance of non-additive effects was observed for tillers per plant, spikelets per spike, grains per spike, 1000-grain weight and grain yield per plant under both normal and late sowing conditions. Plant height showed high additive variance and over dominance variance under both sowing conditions. GA-2002 was the best general combiner for tillers per plant, spikelets per spike, grains per spike and grain yield per plant under both plantings, while SH-2002 for 1000-grain weight under late sowing. Chenab 2002 was the best combiner for 1000-grain weight under normal planting. Cross combinations involving GA-2002 and SH-2002 proved to be useful in selecting high yielding genotypes for normal as well as late sowing conditions.