Department of Crop Physiology, University of Agricultural Sciences, GKYK, Bangalore560065
The effect of prolonged periods of soil moisture stress on the seed and kernel oil content in 24 sunflower germplasm has been examined. Both early (41-71 DAS) and late stress (58-93 DAS) did not adversely affect the per cent seed and kernel oil content while the mean seed yield, test weight and total dry matter were reduced, especially under early stress. The relative stability in the seed oil content of genotypes under moisture stress is explained partly by its relation to the variation in the kernel/hull ratio. The constancy in seed and kernel oil content is discussed in the content of physiological constraints determining oil biogenesis and the evolutionary significance of seed oil to seedling fitness.
