This investigation was directed to determine the manifestation of heterosis, types of gene action, heritability and their interactions with locations. There for many vegetative, earliness and fiber traits were studied in 60 three- way crosses of Gossypium barbadense, L. The parental varieties: 6022 (P₁), Suvin (P₂), Pima S₇  (P₃), Giza 85(P₄), Giza 88(P₅) and Giza70 (P₆) were crossed to obtain these 60 hybrids. The parental varieties, their 15F₁ crosses and their 60 three way crosses were evaluated at two locations: (Sakha Agric. Res. Station and Cotton Research Experimental at Abo-Kebir, EL-Sharkia Governorate).
The results showed highly significant differences among all the evaluated genotypes for all studied vegetative, earliness and fiber traits. The results also indicated that the mean performances of genotypes revealed that the better means were observed for (P₃ x P₅) x P₆ for number of fruiting branches per plant, (P₃ x P₆) x P₂ for number of vegetative branches per plant, (P₅ x P₆) x P₁ for first fruiting node, (P₁ x P₃) x P₂ For number of days to first flower, and number of days to first opening boll, (P₁ x P₄) x P₂ for fiber fineness, (P₁ x P₃) x P₆ for uniformity ratio and (P₃ x P₄) x P₅ for 50% span length and 2.5% span length.
The obtained values for the heterosis of the mid-parents (H._MP%) and the better parent (H._BP%) were significant and exhibited desirable estimates for all studied traits. These results indicated that the additive genetic variances and additive by dominance epistatic genetic variances were predominated and effected in the expression of all studied traits.
The results also illustrated that most studied traits showed high, intermediate or low estimates of heritability in broad (h²_b.s%) and narrow (h²_n.s%) senses for different studied traits. The heritability values in broad sense ranged from 98.85% for number of fruiting branches per plant to 99.98% for span length 50%.  On the other hand, the heritability values in narrow sense ranged from 7.96 to 15.61%, for uniformity ratio % and number of days to first flower, respectively.