TWELVE sunflower genotypes were evaluated for two years; 2013 ……and 2014 at three locations; Agricultural Research Stations of Shandaweel (location 1), Al-Arish (location 2) and El-Ewyinat east (location 3). Genotypic and phenotypic variances, their coefficient of variation, heritability and genetic advance were assessed. As well as study the interrelationships among oil yield attributers using genotypic and phenotypic correlation and path coefficients analysis were done. The experiments were conducted in a randomized complete block design with three replications in the field. Results proved that significant differences were observed among sunflower genotypes, for all studied characters in the three locations over two seasons. The elite genotype No 7 (Line120) surpassed the two check cultivar (Sakha 53 and Giza 102) recording the maximum values of seed yield in the first location with produced the maximum values in the second location for head diameter and seed yield and recording the maximum values of head diameter, seed yield and oil yield in the third location.
Estimates of heritability in broad sense at the three locations were varied from; 26 - 97%, 29 - 96% and 57-97%, respectively. Results also indicated that, highly significant and positive correlation coefficients were obtained between oil yield and some studied traits at the genotypic and phenotypic levels in the three locations. According to path coefficients analysis (at genotypic and phenotypic levels), the traits, i.e. days to 50% flowering and plant height in location 1, days to 50% flowering, plant height, head diameter and 100-seed weight in location 2 and 100-seed weight and seed yield/plant in location 3 were important predictors of oil yield indicating their magnitude as selection criteria to obtain a valuable gain of selection for oil yield in sunflower.