Control of the rice weevil Sitophilus oryzae (Coleoptera : Curculionidae)‎ using some insecticide alternative safe methods

Abstract EN

This work aimed to evaluate the efficacy of certain safe control methods against the rice weevil Sitophilus oryzae (L.) (Coleoptera: Curculionidae).

Adults of S.

oryzae were exposed to CO2 or N2 gas differ in relative humidity content at two degrees of temperature.

Mortality of insect was influenced significantly by the level of relative humidity in the inert gas ambient.

The highest percentages of insect mortality were recorded for lowest and the highest level of humidity at both degrees of temperature.

At the moderate levels of humidity (50 and 60%) the insect mortality was slightly reduced than that of the lowest and the highest levels of humidity at both degrees of temperature, especially for the shortest exposure periods.

It was showed also that a complete mortality was occurred for the insects exposed to the CO2 at the lowest (35%) and the highest (80%) levels of humidity.

Four doses of ECO2-Fume gas (30, 35, 40 and 50 g\m3) were tested against the different developmental stages and adults of S.

oryzae in wheat grains piles under natural conditions.

All tested doses induced a considerable control for all stages of the rice weevil, efficacy was increased as the dose increased, so that, a dose of 50 g\m3 induced 100% mortality of all insect stages after 3 days of treatmen.