Abstract:
The rate of production and productivity of maize are affected by various insects before and after harvest. Chemical insecticides are usually carried out to protect stored products. Even though chemicals insecticides play a beneficial role in controlling of insect pests they do have a negative impact like, causing environmental pollution, have toxic residue in food, promote insecticidal resistance, effect on beneficial and non target species, have risk to the safety of the worker and have high cost. The current experiment were conducted to evaluate the efficacy of botanical powder of N. tabacum and P. dodecandra and their solvent (ethanol and acetone)extracts against S. zeamais under laboratory condition (30 – 330c and 70 – 75% RH). The test insect was reared feeding on the glass jars that have disinfected maize grain. For comparison Tanphos (0.125/150g) and untreated maize grain also included as standard check. The experiments were arranged in a completely randomized design with three replications. One hundred percent mortality of S. zeamais was get on the maize grain treated with the seed powder of P. dodecandra and Leaf powder of N. tabacum at the concentration of 15g/150g after 10 days. At the concentration of 10g/150g of grain, both botanical powders cause more than 90% mortality of adult S. zeamais. In addition to that ethanol and acetone extracts of P. dodecandra and N. tabacum caused 100% mortality of adult S. zeamais within 24 hr after treatment application at the rate of 15g/100ml of solvents. Moreover the other concentration was also effective and resulted in more than 80% mortality of maize weevil. The maize grain treated with the powder and solvent extracts of the plant material also reduced progeny production by the adult maize weevil. Both botanical powders at the concentration of 15g/150g resulted in more than 90% reduction in progeny production. . The botanicals powder did not affect the germination capacity of maize seed. In general, both plant material powders and solvent extract treatments can be used as an alternative method of pest control mechanisms and also can give an effective control of S. zeamais. However, further investigation of those plant powders under farmers’ storage condition and developing effective rates and formulation is needed.