مطالعه تأثیر نقاط کوانتومی گرافن سنتز‏شده با روش سبز مبتنی بر عصاره‌ی آبی گیاه کلپوره(Teucrium polium L.) علیه نماتد Meloidogyne javanica در شرایط آزمایشگاهی

The root-knot nematodes (Meloidogyne spp.) are amoung the most important plant parasitic nematodes worldwide. In the present study, the effect of the aqueous leaf extract of felty germander (Teucrium polium L.) at the rate of 0, 0.25, 0.5, 0.75, and 1%, and 0, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.4 and 0.8%, was studied on egg hatching and the mortality rate of second-stage juveniles (J2s) of M. javanica, respectively, in vitro. In addition, by using the aqueous leaf extract of the mentioned plant at a concentration equivalent to the lethal concentration of 50% (LC50) of J2s, graphene quantum dots nanoparticles (GQDs) were synthesized and at the rate of 0, 0.25, 0.5, 0.75 and 1%, and 0, 0.0125, 0.025, 0.05, 0.1, 0.2, 0.4 and 0.8% was studied on egg hatching and the mortality rate of J2s of M. javanica, respectively, in vitro. For this purpose, 100± 5 eggs or J2s were poured into the wells of a 96-house polyester plate containing 200 µL of the mentioned extract or as-synthesized GQDs and kept at 27 ͦ C and in the dark condition. The experiment was conducted in a completely randomized design with four replications. Mortality rates of J2s and nematode eggs hatching were evaluated after 48 and 120 hours, respectively. The results showed that the aqueous leaf extract of T. polium and as-synthesized GQDs in the highest concentration decreased egg hatching by 80.94% and 81.65% compared to the control, respectively. It was also found that the mortality rate of the J2s was directly related to the increase in the concentration of the aqueous leaf extract of T. polium and as-synthesized GQDs, and the highest concentration caused the death of J2s by 93.55% and 96.83%, respectively. The LC50 value for the aqueous leaf extract of T. polium and as-synthesized GQDs was 0.17 and 0.07%, respectively. The results of this study showed more extraordinary ability of as-synthesized GQDs to increase the mortality rate of J2s and reduce the hatching rate of M. javanica eggs compared to the aqueous leaf extract of T. polium.