A Comparative Study on Diallel and Partial Diallel Analyses

An effort is made to compare the diallel and partial diallel analyses for the quality component, fitness and grain yield in some varieties of Sorghum, differing in grain quality and panicle shape. The presence of significant reciprocal effects did not produce any disturbance in the efficiency of general combining ability effects and subsequent selection of parents in partial diallels. There was an increasing trend in the magnitude of specific combining ability variances from full diallel (S=7) to reduced size of partial diallel (S=3), whereas the estimates of general combining ability effects did not show any such pattern in the change in magnitude. Additive component was much higher than non-additive component in diallel. The estimates of general combining ability effects remained unaffected leading to successful selection of top four parents in as low a size as s=3 of partial diallel. Hence for characters wherein the heri-tability was high and degree of dominance was low even the smallest number of crosses per parent (S=3) gave reliable estimates without adversely affecting the efficiency of selection. These conclusions remained valid at both locations, Delhi and Coimbatore even when the differences in the performance of varieties at two locations were brought out.