Soil Conservation Research Centre, Bellary and Division of Genetics, I.A.R.I., New Delhi-110 012
**Present address: Genetics and Plant Breeding Dept., GIMPO, Lucknow, 226 007, India.
*Authorised for publication as paper No. 35-6/78. (Pl. Bre.) by the Director, Central Soil & Water Conservation Research & Training Institute, Dehra Dun (India).
Germ plasm collections of safflower involving 30 genotypes representing a broad spectrum of variability available in the traditional areas of its cultivation in India and 10 introductions from U.S.A. were subjected to multivariate analysis for assessing the nature and degree of intra-specific divergence in two diverse environments. Based on 14 characters, the entire collection formed 14 constellations in stress and 13 in non-stress environments. A predominant section of the indigenous collection including improved varieties currently recommended in different areas showed relatively greater homogeneity for a multitude of characters and formed closely related groups. The disposition of safflower populations from various sources into different constellations did not follow any consistent pattern in relation to geographic diversity. The composition of clusters and their mutual associations in general, remained more or less stable in both stress and non-stress conditions. Various characters such as height of branching from ground level, size and number of capitula, seed number and weight, yield per plant and hull percent exerted marked influence on genetic diversity both at inter- and intra-cluster levels. The relative importance of these characters for genetic divergence, however, varied depending on growth conditions. The degree of spininess showed negligible role in influencing intra-specific divergence in the crop. Unlike indigenous collections, majority of the exotics showed poor adaptability to our conditions. The implications of these studies on future breeding strategies to be adopted for elevating the overall productivity levels of safflower are discussed.
