RELATIVE USEFULNESS OF TRIPLE TEST CROSS METHODS FOR ESTIMATING ADDITIVE AND DOMINANCl IN BREADWHEAT

Abstract

Forty-five triple test cross progenies of wheat were produced by crossing 15 true breeding lines/varieties with three testers and grown in normal and stress environments. The data on parents and Fts were analysed for days to heading, plant height, tillers/plant, total biomass, grains/ear, 10llO-grain weight and grain- yield/plant to determine the relative usefulness of three methods for estimation of additive and dominance components of genetic variation. The variance of parents (q~) estimated the additive component better than the two other methods (Iu + I 2i and I u + I 2i + I 3;). The methods 4 q 3+ 9 ~ (Iti + I 2i -Pi) and 25 (q2 (2 Itl-Pi) pooled with ~ (2 I 2i-Pi)] pro'Vidld better estimates of dominance component than I tl-L2rmethod in the presence of epistasis. These two methods also gave similar estimates of dominance component.