This research involved extracting the crude and volatile oil from Casuarina cunninghamiana leaves, which are part of the Casuarinaceae family. It also involved doing a phytochemical screen to determine the yield of the crude and volatile oil extract., The antifungal effects of crude and volatile oil extract depended on concentration; for example, a methanol crude extract of leaves expressed its maximal inhibitory zone at 400 mg/ml, which was 20.12 mm, but at low concentrations of 100 mg/ml, it was 13.2 mm. While the inhibitory zone against C. albicans at a high concentration of ethanol crude extract of leaf reached a diameter of 1 9.12 mm. In contrast, the inhibition zone width against C. albicans in the high concentration of hexan volatile oil extract reached 22.15 mm despite the low concentration of reported 12.3 mm. The low concentration of 13.12 mm was however measured. In hexan volatile oil extract, C. albicans exhibited great activity. The width of the inhibitory zone, however, is against C. albicans obtained a diameter of 21.13 mm at a low concentration of 14.12 mm of ether volatile oil extract. The study’s objective is to determine the best extract (crude or volatile oil extract), as well as the best alcoholic extract (methanol, ethanol, ether, and hexan), and the best concentration of the study extracts.

Random Amplified Polymorphic DNA (RAPD) indicators were carried out to prepare the genetic fingerprints of six species of the genus Tegates. The discrepancies between the replicates of each species (their numbers and molecular sizes) were revealed after the replicates of the samples were migrated onto agarose gel and stained with ethidium bromide. 10 primers were selected, which showed different replication products among the studied species, as those primers showed 63 polymorphic bands out of 468 total bands. Each selected starter produced between 23 bands (OPD-18) to 78 bands (OPF-04). The largest number of divergent bands (15 bands) generated by the primer OPD-13, while it appeared that the least number of divergent bands (3 bands) which was generated by the primer OPD-18. The primer efficiency ranged from 0.20 in (OPD-13) to 0.09 in (primer OPA-04). It was found in this study that the primer OPD-13 had the highest discrimination ability, while the primer OPD-18 had the lowest value of the discrimination ability. The lowest genetic dimension was (0.3755) between the two species T. erecta and T. patula, while the largest genetic dimension was (0.8466) between the two species T. patula and T. tenuifolia. The phylogenetic tree through the unweighted pair-group method of arithmetic means (UPGMA) that is, based on the tree of phylogenetic relationships revealed two main genetic groups. The general analysis of the results showed that the genetic relationships between the species of the genus Tegates are related to some morphological traits as well as to the original origin and at the level of molecular genetics.