One of the methods to combat citrus blast disease is chemical control, which due to the high cost of preparing toxins and the effects of toxins on the environment, researchers tend to find less expensive methods and also have no adverse effects on the environment. The result of the method of struggle that has received much attention today is the use of natural bactericidal compounds, some of which are found in the extracts of native medicinal plants. In this study, several different methods of extraction of medicinal plants and their application in inhibiting the growth of citrus blast causing bacteria have been investigated. These herbs include basil (Ocimum basilicum), mint (Mentha pulegiu), rosemary (Rosmarinas officinalis), lavender (Lavanduia anyustifolia), thyme (Thymus persicus) and nettle (Urtica Dioica). The effect of these extracts on the extent of inhibitory aura in Nutrient Agar medium Against each other pathogenic bacteria and against copper oxychloride toxin and tetracycline antibiotic were measured and compared. Finally, the best method to obtain a more inhibitory plant extract was first the analytical method, then soaking and clearing, and finally boiling with stirring; The highest inhibition rates were related to peppermint, mint, thyme, lavender, nettle, rosemary, and finally antibiotics and copper oxychloride toxin, respectively. The application of these extracts was also sprayed on the surface of citrus orchard and reduced the severity of the disease, but no significant difference was observed between the types of extracts in the degree of inhibition in the orchard.
