A CORRELATION AND PATH-COEFFICIENT ANALYSIS OF SEED YIELD COMPONENTS OF SUNFLOWER UNDER LOAMY SAND AND CLAY SOIL CONDITIONS

The present investigation was carried out at Fac. Agric. Exper. Farm (clay soil), and Arab Al-Awamer Res. Stn. ARC. (loamy sand soil), to study phenotypic and genotypic correlations among traits of 24 genotypes of sunflower (4 females, 4 males and 16 hybrids). Path-coefficient analysis was done for the four components of seed yield/head (number of seeds/head, husk weight of 100 seeds, oil weight of 100 seeds and kernel weight of 100 seeds) with the dependent character; seed yield/head. The analysis of variance indicated significant (P<0.01) mean squares of environments, genotypes and genotype x environment interaction for all traits. Days to 50% flowering showed low correlations with both of seed yield/head and oil yield/head at genotypic and phenotypic levels from the combined data. Genotypic and phenotypic correlations were high in magnitude between plant height, head diameter, stalk diameter, 100 seed weight, husk weight in 100 seeds, oil weight in 100 seeds, kernel weight in 100 seeds and number of seeds/head, and each of seed yield/head and oil yield/head at both sites and the combined. However, the correlations of husk % with oil and seed yield/head were negative in clay soil and the combined. The other correlations among traits at both sites and combined were discussed. The direct and indirect effects of the contributing traits of seed yield/head varied greatly from loamy sandy soil to clay soil. The breeder should evaluate the breeding materials under a variety of environments, to get reliable estimates of genetic parameters. The combined estimates of direct and indirect effects of the seed yield/head component traits at genotypic level could be ranked as husk weight followed by number of seeds/head, kernel weight and oil weight in 100 seeds.