Division of Genetics, Indian Agricultural Research Institute, New Delhi-12
*Part of a thesis submitted by Ziauddin Ahmad in partial fulfilment of the requirements of the Ph.D. degree of the Indian Agricultural Research Institute, New Delhi.
The components of genetic variation for the developmental traits indicated the predominance of additive genetic variance in the F2 and F3 of a 22 × 22 diallel in dwarf Pennisetum. However, these estimates were lower than those obtained with the F1 with substantial reduction in σ2g but increase in σ2e. The relative ranking of parents on the basis of mean performance and the gca effects were similar in the F1, F2 and F3 diallels. Among them, seven were found to be promising in both the generations. Parent 1 was outstanding and combined well for quality characters and rust resistance. These parents with high productivity were also synchronous in tillering indicating their developmental stability. The study has indicated the feasibility of using the F2 and F3 of diallels for estimating combining ability provided large number of parents are involved and no selection is practised at any stage and large populations of the segregating generations are included in the experiment.
