Efeito de diferentes extratos vegetais no controle de Acanthoscelides obtectus e Sitophilus sp.

Abstract

The main method of controlling pests in stored grain is the chemical, mainly synthetic pyrethroids and phosphates of aluminum or magnesium, and high-toxicity insecticides and possessing no selectivity. Several problems can be found with the constant use of chemical control, such as pest resistance to insecticides. A very relevant factor has been the difficulty of storing grain produced in organic systems. By owning a few studies in the area, organic products suffer the action of insects throughout the storage period, increasing its production and by making the cost of production even higher. The experiment was conducted at the State University of Goiás in the city of Annapolis. Were used to control insects alcoholic extracts of 13 plant species, easily found in any region of the country. The plants used for the control were: Allium sativum, Cymbopogon winterianus, Chisantemum cinerariaefolium, Chenopodium ambrosioides L., Eucalyptus citriodora, Nicotiana tabacum L., Sesamum indicum, Ricinus communis L., Brassica juncea, Azadirachta indica, Capsicum sp. L., Piper nigrum L. and Sapindus saponaria L. in 6 doses, 0, 0.04, 0.08, 0.12, 0.16 and 0.20 mL L-1. The insects were used to control the Acanthoscelides obtectus and Sitophilus sp. L. Each experimental unit included 10 adults not sexed. After 48 hours of the control was done by counting mortality. The experimental design was completely randomized in a factorial design 13 x 6 for the two insects, with the factors dose and extract with three full reps. The results showed that: the extract of Sesamum indicum, at a dose 0.16 mL L-1 showed 100% mortality of insect Acanthoscelides obtectus the extract of Piper nigrum, dose 0.04 mL L-1 showed 100% mortality of insect Sitophilus sp.