Abstract
The main objective of this work was to evaluate the efficacy of the extract of the coastal plant Salicornia fruiticosa and the silver nanoparticles prepared from it against the 4th larval instar of the Culex pipiens mosquito. The leaves of this plant were obtained from the Kharar region along the Western Red Sea Coast of Saudi Arabia. The experiments were carried out at the premises of the mosquito research station at King Abdulaziz University, Saudi Arabia. The results showed an effective action of S. fruiticosa against the laboratory reared 4th instar larvae, where the LC50 = 2.39 ppm and the Lower Confidence Limit (LCL) = 2.16 ppm, whereas the Upper Confidence Limit (UCL) = 2.62 ppm. Moreover the efficacy of the silver nanoparticles produced from plant extract gave a high significant efficacy, where the LC50 = 0.276 ppm with the Lower Confidence Limit (LCL) = 0.14 ppm and the Upper Confidence Limit (UCL) = 0.391 ppm. The results showed that the synthesis of silver nanoparticles prepared from the plant extract gave a higher efficacy when compared to the plant extract alone, with approximately 8.66 doubled. Therefore, the extract of the coastal plant S. fruiticosa and the silver nanoparticles that were prepared from it contained promising active compounds that could be used against the 4th instar larvae of the mosquitoes which transmit the causal pathogens of diseases as logistical rational safe method in the overall containment and control.