In comparison to a chemical nematicide (Oxamyl), humic acid and three commercial bioagents namely Abamectin (Streptomyces avermitilis), Clean Root (Bacillus subtilis) and Nemastrol (chitinase, glycosynolates, Glucanase, cytokinins and flavonoids) were tested in a greenhouse and field to see how they affect the population density of root-knot and citrus nematodes and, as a result, the effects on plant growth parameters. In greenhouse test, humic acid gave the highest results in terms of increasing total plant fresh weight (403.8 %) and shoot dry weight (400%) compared to untreated plants. Regardless chemical nematicide used, Abamectin showed the best results in suppressing Meloidogyne incognita reproduction with a reduction percentage of (85.4%), while Nemastrol resulted the best reduction percentage of Tylenchulus semipenetrans population (84.4%). Six months after treatment, Nemastrol showed the highest decrease percentage of root-knot nematode (82.4%) and citrus nematode (75.6%) in a field experiment. On the other hand, Oxamyl and humic acid outperformed other treatments in terms of improving the percentage of fruit weight (166.84 and 145.87 %), respectively. Furthermore, all treatments had an impact on the fatty acid composition of olive oil. At the same time, compared to untreated trees, such treatments resulted in lower peroxidase and polyphenoloxidase activities. In terms of phenol content, it was clear that Nemastrol, followed by humic acid improved total phenol content. However, Clean Root gained the highest overall protein concentration. Furthermore, humic acid increased the total carbohydrate level.