Genetic variability studies for yield and yield components in sunflower (Helianthus annuus L.)

Genetic variability is a crucial tool for improvement of seed yield in sunflower. The analysis of variance of 23 hybrids revealed significant differences for all nine characters studied. The genotypic and phenotypic variation was high for seed yield per plant, head diameter and test weight indicating these characters were amenable for improvement by selection. All characters studied were least affected by environment as shown by correspondence between phenotypic co-variance (PCV) and genotypic covariance (GCV). High heritability coupled with the high genetic advance was recorded for plant height, test weight, seed yield per plant, volume weight and head diameter. High heritability along with moderate genetic advance was observed for days to 50 per cent flowering and oil content indicating additive gene action controlling these traits.