The data from an experiment in cotton consisting of three testers and 12 lines selected deliberately have been analysed. The investigation showed higher specific combining ability variance for yield of seed cotton and number of bolls, indicating the predominance of non-additive gene action. Of parental lines, H777 was found to possess high g.c.a. effects for seed cotton yield, number of bolls and number of sympodes. Parent H842 contributed only for boll weight, whereas H655 was good general combiner for number of monopodes. There appeared to be better chances for increasing the yield by exploiting hybrid vigour for the number of bolls and boll weight. The presence of marked non-additive gene effects, in addition to additive gene effects, indicated the need for exploiting both the fixable and non-fixable components of genetic variance for increasing productivity in cotton.

Four F3 populations of chickpea (Cicer arietinum L.) were simultaneously evaluated for yield in an F3 yield trial and in single plant progeny rows. Ten high yielding, 10 low yielding and 10 randomly sampled lines, along with 10 lines visually selected for yield from the progeny rows, were retained for further evaluation. The lines from each of the four selection groups in each population were bulked and evaluated in a replicated yield trial at three locations and four environments. The bulk of visually selected lines was not superior in yield to the bulk of randomly sampled lines at all locations. The present results indicate that an early generation yield testing selection procedure is more efficient than visual selection for yield improvements in chickpea.

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At present, the parents are included in the experimental material for judging the performance of crosses over parents and for calculation of heterosis but they are ignored for combining ability analysis of Partial Diallel Crosses due to the non-availability of the method of analysis for such designs. To satisfy the practical need of the breeders on one hand and to remove the statistical objections on the other hand, a method of analysis of Partial Diallel Crosses based on circulant sample including parents has been presented in this paper. A numerical example is given for llustration of technique.