Évaluation de l’efficacité du thiaméthoxame sur coelaenomenodera lameensis (coleoptera, chrysomelidae, hispinae) ravageur du palmier à huile (elaeis guineensis) en Côte D’Ivoire

Abstract

Insecticide injections into palm oil tree trunk is considered as the ultimate solution in control of Coelaenomenodera lameensis (Coleoptera: Chrysomelidae) for crop preservation. This study was designed to evaluate the impact of different concentrations of thiamethoxam in the control of dangerous stages of C. lameensis. Results of this investigation were compared with those of two other well-known pest control insecticides
(cartap and thiocyclam-hydrogenoxalate). Thiamethoxam was tested following the endotherapeutic way. Observations were made on the mean infestation index of larvae and adults for treatments and controls. The results showed that thiamethoxam was more effective on larvae than on adults’ stages (96 against 89 % mortality). The mean effective
dose obtained was 0.96 g of active ingredient per tree, which corresponded to a concentration of 0.040 g/ml injected at a ratio of 24 ml per tree. The persistence of this insecticide was 16 weeks. Treatment with cartap or thiocyclam-hydrogenoxalate showed a greater efficiency on adults with a persistence lasting from 6 to 8 weeks. Thiamethoxam, with its systemic action can be used as a good alternative to monocrotophos which is as well
a systemic insecticide forbidden for its high toxicity.

Keywords : Palm oil tree, Elaeis guineensis, Coelaenomenodera lameensis, thiamethoxam.