Effect of Three Insect Growth Regulators on The Avian Malaria Vector-Culiseta longiareolata Larvae- Field Population

A number of species within the Culicidae family are responsible for the transmission of pathogens to animals and humans. The study of these species and the fight against these natural enemies represent a significant area of concern for scientists in the present era. An inventory of Culicidae in the M'chouneche region (34° 56' 59.99" N, 6° 00' 0.00" E) (Biskra, southeastern Algeria) was conducted in various breeding sites between November 2022 and May 2023. Four species of Culicidae were identified: Culiseta longiareolata, Culex pipiens, Culex theileri, and Anopheles multicolor. To assess the efficacy of three insect growth regulators (Lufenuron, Teflubenzuron, and Spirotetramat) on the fourth larval stage of Cs. longiareolata, control tests were conducted under experimental conditions. Lufenuron demonstrated a markedly higher toxic effect, with a mortality rate of 57% (ranging from 0 to 100%), compared to Spirotetramat, which exhibited an average mortality rate of 37.71% (ranging from 0 to 80%), and Teflubenzuron, which showed an average mortality rate of 12.08% (ranging from 0 to 45%). The mortality rates demonstrated an increase from one concentration to the next over time. Furthermore, the correlation coefficient between the two factors (time and concentration) and the mortality rates was found to be low at 30%. Individuals that were treated after reaching the adult stage exhibited a notable delay in their development. For concentrations of 20 mg/L and 40 mg/L, the delay duration was approximately two days ± 12 hours. In contrast, the third concentration (80 mg/l) resulted in a development delay of approximately three days±15 hours.