Genetic divergence was evaluated in 31 breeding lines from four Brassica species using Mahalanobis’ D2. A new
method of grouping using D2 values was used to group the 31 lines, based on diagnostic morphological traits (called
morphoqts). Isozyme variation of the individual enzymes esterase and glutamate oxaloacetate was quantified by five
parameters (called isoqts) developed earlier. Grouping by the same method was also done based on the isoqts, and the
grouping by isozymes was compared with that by morphoqts. Overall, there was an agreement of 73% suggesting that
isoqts can be used in the choice of parents and also first stage selection of segregants in the laboratory. It was suggested
that such an exercise would help to take care of season-bound and field-related problems of breeding. The new
isozyme QTs, within lane variance of relative mobility and relative absorption, accounted for about 50% of the total
divergence. The utility of the new method and isoqts in cost-effective breeding were highlighted.