Abstract. Hamaidia K, Soltani N. 2021. Short communication: New report of Aedes albopictus in Souk Ahras, Northeast Algeria. Biodiversitas 22: 2901-2906. The present paper reports the occurrence of Aedes albopictus (Skuse), an aggressive Asian tiger mosquito in the city of Souk-Ahras (Northeast of Algeria). A “26 April” estate’ inhabitants (Souk-Ahras province) have reported unusual daytime bites by a striped mosquito. On early September 2020, an intensive field inspection was carried out for potential mosquito breeding sites in the locations around the city. A total of 105 specimens (8 larvae, 24 pupae and 73 adults) of Ae. albopictus were collected in a pile of old tyres in a residential garden. After previous records of this species in Algeria, this is the first evidence of its presence in Souk-Ahras province, and the findings enhance combined public participation with professional validation in surveillance of vector borne-diseases programs with emphasis on the need for sensitising citizens about controlling this important vector.

Melia azedarach L. (Meliaceae) is a botanical species with focal point of global research for its biological properties. The Melia azedarach tree is distinguished by its rapid growth, its adaptation to different temperate zones, as well as its insecticidal properties. All this made us think of exploiting it in biological control against different stages of mosquitoes. To this end, we aim, through the present work, to evaluate the effectiveness of Melia azedarach extracts against Culex pipiens mosquito. More specifically, our study focuses on determining the chemical composition of Melia almond oil, as well as the larvicidal, ovicidal and repellent activities on Culex pipiens L. mosquito as well as the activities of acetylcholinesterase (AChE) and glutathione-S-transferase (GST). Almond oil was extracted by a Soxhlet and subjected to gas chromatography-mass spectrometry (GC/MS). The yield was found to be 35.17%. The chemical composition revealed the presence of various phytoconstituents. A total of 7 compounds were identified, the main ones being 9,11-Octadecadienoic acid, methyl ester, (E,E)-(79.32%), 9-octadecenoic acid (Z)-, methyl ester (13.24%), hexadecanoic acid and methyl ester (3.69%). The larvicidal bioassays were performed according to the protocol recommended by the World Health Organization with concentrations varying from 20 to 80 mg/L depending on the exposure time (24, 48 and 72 hours). The almond oil exhibited remarkable larvicidal activity against fourth instar larvae and the lethal concentrations were determined (LC 25 = 23.70 mg/L, LC 50 =35.49 mg/L, LC 90 =79.61 mg/L). The results also showed that the oil caused an ovicidal activity with a significant effect on egg hatch. The recorded hatching percentages were respectively 88.79% and 72.40% for the LC 25 and LC 50 , and this compared to the control series. Moreover, this oil exhibited significant repellency against adult mosquitoes. Furthermore, the enzymatic measurements performed on LC 50 and LC 90 treated larvae revealed a neurotoxic activity and a stimulation of the detoxification system as evidenced, respectively, by an inhibition of AChE and induction in GST activity. Overall, our data proved that Melia azedarach almond oil could be considered as a potent biorational alternative to synthetic insecticides for mosquito control.

No abstract

No abstract

No abstract