Genetic analysis of sunflower genotypes under water stress environments

The present investigation was undertaken in the Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana, Punjab to evaluate 41 genotypes of sunflower (Helianthus annuus L) for morphological and yield traits affecting water use efficiency under different water stress environments. The traits under study were days to 50 per cent flowering, days to maturity, plant height, head diameter, seed yield per plant, 100-seed weight and oil content. Analysis of variance revealed significant differences due to genotypes and environments for all the characters under study. Among the four environments W ₁ (control) yielded the maximum value for all the parameters followed by W₄ (withholding of irrigation at anthesis completion stage and thereafter complete withholding of irrigation after soft dough stage), W₃ (withholding of irrigation at 50 per cent flowering stage and soft dough stage thereafter complete withholding of irrigations after hard dough stage) and W₂ (withholding of 2^nd irrigation ie before button stage and thereafter complete withholding of irrigation after soft dough stage). The estimates of heritability and genetic advance were found maximum for seed yield per plant followed by 100-seed weight indicating the predominance of additive gene effects. Hence this trait can be improved to a considerable extent by limited selection cycles. Estimation of GCV and PCV values were also higher for seed yield per plant as compared to other traits indicating high genetic variability for this trait. The genotypes P-87-R, P-93-R, P-100-R and P-110-R were identified as water use efficient genotypes. The stress environment W₄ (withholding of irrigation at anthesis completion stage and thereafter complete withholding of irrigation after soft dough stage) could be considered as good as the control to realize maximum yield in sunflower.