Emprego de óleos vegetais e glicerina no controle do gorgulho do milho.

Abstract

Among the plagues that focus laid up over the corn (Zea mays L.). The Sitophilus zeamais weevil stands out, whereas when it get contact with the corn seeds it reduces in a short period of time, its quality, causing a high infestation. Thus, in order to seek for alternative means, aimed at controlling this plague, this study purpose to evaluate two kinds of oils (castor bean’s and coconut’s) and an organic compound glycerin, as the action of repellency, insecticide and protective of Zea mays on the number of adult weevils present in a mass of seeds treated with these products after inoculation of Sitophilus zeamais, as the viability, infestation and moisture content of the seeds in pet, packaging during storage. The free-choice tests (repellency, attractiveness and unresponsive) were performed in the laboratory, without control of temperature and relative humidity, using doses of 0,02; 0,06; 0,08 and 0,10 mL / 20g of corn. For storage, the seeds were treated with the same compounds but at doses of 0,05; 2,03 mL/500 g of corn. Every 30 days (total 150 days) were evaluated, infestation and their germination at first count (stamina) and determined the moisture content of maize seed. The delimitation was completely randomized with treatments arranged in a factorial scheme which the quantitative factors were revealed by the regression, analysis of variance. It was concluded, based on studies, that coconut oil and castor oil showed higher repellency of adult insects in the same controlled oil at a dose of 2 mL, the rate of infestation thereby protecting, the seeds, when stored.