Assessment of selected biological traits of the red palm weevil Rhynchophorus ferrugineus (Olivier, 1790) reread on apple and efficacy evaluation of thiamethoxam and emamectine benzoate for its control

Abstract

Laboratory insect pests’ readings are essential to better understand their biological traits, assess their host plant and assess the efficacy of insecticides. This work aims at studying the selected biological traits of the red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) 1790 reared on semi-artificial died based on apple slices and maintained in natural conditions. Furthermore, the adulticide and larvicide efficacy of two insecticides recommended for the control of this pest which thiamethoxam and emamectine benzoate was assessed in the laboratory. Results showed that, on apples slices and maintained in natural conditions the Average daily fecundity is 2.5 eggs/female. The hatching rate of eggs ranged between maximum of 76% in October and a minimum of 5% in the end of November. The shortest egg incubation period is 3 days. However, starting from the first week of November, this duration exceeded 10 days. The RPW develops 7 larval stages requiring 63 days. Fourth instar larvae were 80 larger than first instar ones. The assessment of the efficacy of two insecticides: thiamethoxam and emamectine benzoate showed that the 2 products are efficient against larvae and adults ensuring 100% of larval mortality 24 hours after their application. However, ememectine benzoate is more efficient against adults than thiamethoxam. In the case of emamectine benzoate it ensured 100% adult mortality 96 hours after its application with a choc effect preventing food intake starting from the first hours of application.