Diatomaceous earth as alternative in the control of Sitophilus spp. in paddy rice

Abstract

The use of alternative methods to control pests in substitution to chemical agents has been standing out all over the world, in the search for sustainability and food security in the production chains. Thus, the objective of this study was to evaluate the effect of diatomaceous earth (DE) dust on the control of Sitophilus spp. in paddy rice. The experimental design was completely randomized, in a 5X3 factorial scheme, with 5 doses of DE (0, 250, 500, 750 and 1000g of TD.t^-1) x 3 periods of previous treatment of rice with TD (0 , 7 and 14 days) x 3 periods of evaluation of insect mortality (7, 14 and 21 days). Samples of 100 g of rice were placed in pots with 20 adult insects of Sitophilus spp. not sexed, where the mortality of adult insects was evaluated. The use of DE in the control of Sitophilus spp. in paddy rice it was significant, but insect mortality varied according to the dose and the time of exposure of these to the control agent. In treatments in which rice husks were previously treated for 14 days, insect mortality occurred more slowly and in a lower percentage. The results also indicate that the most efficient dosage was 500g.t^-1 associated with the previous treatment period of 7 days. The use of diatomaceous earth presents itself as a good alternative for insect mortality in stored grains due to its economic and environmental advantages.