Genetic Components Derived Parameters and Heterosis in Okra under Saudi Arabia Conditions.

Four parental genotypes of okra were crossed in complete diallel design to study the direction and extent of relative heterosis and heterobeltiosis for yield and its associated traits for utilization of existing genetic diversity to develop heterotic F1 hybrids in okra. The additive genetic component (D) was significant in all studied traits except average pod weight. Nonadditive (H1 and H2) components were found to be significant in all studied traits. However, the values of the dominant effect (H1) were smaller than the D components for no. of nodes/plant, no. of pods/plant, weight of medium pods, weight of large pods, and total fresh pod yield. The maximum significant MP heterosis in the desirable direction (149.9%) was recorded for the weight of large pods/plot. The maximum significant heterobeltiosis in the desirable direction (120.1%) was recorded for the weight of small pods/plot followed by total fresh pod yield (107.4%), the weight of large pods/plot (104.9%), weight of medium pods/plot (92.1%), average pod weight (51.8%), number of pods/plant (38.4%), and plant height (34.3%). It could be concluded that plant height, average pod weight, and the number of branches could be considered for the development of elite hybrids (heterosis breeding) or inbred lines (pure line selection) in succeeding generations. Therefore, these parameters can be considered for selecting genotypes to improve the pod yield of okra. The superior crosses identified through heterosis analysis were Egyptian Balady × Line 4.1.18 (30.8 ton/ha), Line 4.1.18 × Egyptian Balady (29.8 ton/ha), Dwarf Green Long Pod × Line 4.1.18 (28.3 ton/ha), and Egyptian Balady × Dwarf Green Long Pod (27.6 ton/ha) as these crosses had high performance as well as significant and higher estimates of heterobeltiosis for fruit yield per plant and yield attributing other characters.

Morphological, Biochemical, and Molecular Diversity Assessment of Egyptian Bottle Gourd Cultivars.

The genetic variability and relationships between ten bottle gourd cultivars were evaluated based on morphological, biochemical, and molecular parameters. The results displayed high variability among selected cultivars in terms of photosynthetic pigments, total free amino acids, total phenol content, isozymes pattern, and protein electrophoresis. Furthermore, differences in molecular markers were revealed by the SCoT technique. The peroxidase (POD) and polyphenyl oxidase (PPO) isozymes patterns did not detect significant differences in bands among cultivars. The protein patterns revealed seventeen bands ranging from 126 to 9 kDa and five polymorphic bands representing 29.41%. On the other hand, eight SCoT primers were used to evaluate the genetic variability and relationships between the ten Egyptian bottle gourd cultivars. The results of SCoT analysis detected 44 amplicons with 50% polymorphism. In addition, the results of the phylogenetic tree that is constructed based on the similarity coefficient revealed by SCoT analysis confirm the results of biochemical analysis indicating a genetic relationship between the most efficient bottle gourd cultivars (S1 and S2 cultivars). In addition, there is a genetic relationship among the less efficient bottle gourd cultivars (S4 and S5 cultivars). These results could be beneficial to distinguish among bottle gourd cultivars in the plant breeding programs.