Control Sitophilus zeamais (Coleoptera: Curculionidae) in Maize (Zea mays L.) treated with diatomaceous eart

Abstract

Maize (Zea mays L.) is one of the most important cereals grown worldwide. As the product is sold fresh, the major concern is to maintain the quality of the grain, but its storage is difficult due to wide range of pests that can attack, reducing the quality. The objective of this study was to evaluate the effect of diatomaceous earth in the mortality of maize weevil Sitophilus zeamais in maize grains stored in different dosages and check the exposure time of each treatment. The experimental design was completely randomized with six treatments and five replications. The treatments consisted of increasing doses of diatomaceus eart (DE), in the proportion of zero, 50, 100, 150, 200, 250 g of DE t^-1, all packed in plastic cups of 250 mL. In each plastic cup it was released 20 insects of S. zeamais and they were closed with fabric nylon fine mesh for aeration. The evaluation of insect mortality were performed at 3, 6 and 9 days after infestation (DAI), by counting the living and dead insects in the trays and the possible re-infestation. Treatment with diatomaceous earth in maize (Zea mays) at a dosage of 250 g t^-1 provided better control of S. zeamais.