تقييم كفاءة تراكيز مختلفة من المستخلصات المائية للزعتر البري Thymus syriacus والازدرخت Melia azedarach على الاكاروس الاحمر ذو البقعتين (Tetranychus urticae Koch(Acari: Tetranychidae تحت ظروف المختبر

Abstract

friendly and safe for public health, suitable as partial or complete substitutes for synthetic chemical pesticides that have caused and continue to cause significant negative effects and damage through their use to combat various pests, Biological tests were carried out to evaluate the efficacy of aqueous extracts of wild thyme T. Syriacus and M.azedarach on various growth stages of the red two-spotted mite under laboratory conditions. The results showed that the extracts of the two studied plants had good biological activity on the mite stages treated by dipping plant discs for 5 seconds. with thyme extract being somewhat superior to azadirachta extract for all concentrations used (mother solution, 75%, 50% and 25%).      A significant decrease in the efficiency of the extract was found against the treated stages (eggs, protonymphs, adults) with the gradual dilutions of the extracts, where the degree of effect reached 61.97, 60.56, 40.84, 65.71, 62.85, 42.85 for the mother extract and the concentrations of 75 and 50% for the azadirachta for adult females and protonymphs, respectively. The mortality rate with thyme at the same concentrations mentioned and at the two studied growth stages reached 71.42, 67.14, 52.85, 73.91, 71.01, 55.07% with gradual dilutions and towards adult females and protonymphs, respectively.      The experiments showed that the mother extracts and the 75% concentration of the two studied plants had good effectiveness against the tested mite growth stages, which reached 70% and 60% for wild thyme and azadirachta, respectively. The killing rate of the 50% concentration for wild thyme exceeded 55% compared to the standard control Danikong (Pyflubumide). The results of the experiments showed that the aqueous extracts of thyme and azadirachta had additional effects on some of the biological characteristics of the studied mite, other than killing them. These effects included stunting the growth of the protonymphs and preventing them from reaching the full stage and laying eggs, especially when treated with the mother extract at a concentration of 75%. There was a one-day delay in the hatching of the eggs laid by the females treated with the two mentioned concentrations of the two studied plants. And  also for one day at the time of maturity of individuals resulting from the same eggs and concentrations of wild thyme. The results of the study show the possibility of using wild thyme extracts in integrated management programs for mites under protected conditions for their efficiency and environmental and health safety.