Division of Genetics, Indian Agricultural Research Institute, New Delhi-12
*A part of the thesis submitted by M. M. Verma for the Ph.D. degree of the Indian Agricultural Research Institute, New Delhi.
Multivariate analysis of divergence has shown that in addition to photosensitivity which has been considered the major factor for adaptation in this crop so far, several characters like synchrony of flowering, primary branches, 100-grain weight and specific gravity of the seed were important for genetic divergence. The canonical analysis has revealed that days to maturity, 100-grain weight and plant height were also important. Varieties belonging to diverse D2 clusters not only differed in their mean yield but also in their response for yield in varying environments. Since response to environment is a genetic character, grouping on the basis of regression analysis for yield to choose genetically diverse and stable yielding parents was found to be as reliable as the elaborate multivariate analysis. The bringing together of diverse gene constellations for several attributes will provide stability of performance over wider areas.
