Silício na indução de resistência por não-preferência para ovoposição de Spodoptera frugiperda (Smith) (lepidoptera: noctuidae) e Diatraea saccharalis (Fabricius) (lepidoptera: crambidae) em milho.

Abstract

Maize can harbor a host of insect pest species that can be a major cause of crop loss and make its cultivation harder. The silicon amendment in grasses has been showing to be an efficient alternative in the integrated pest management, including various mechanisms and stages of insect-plant interaction. With that in mind, the objective of this study was to evaluate the effects of silicon in the resistance induction to non-preference for oviposition of Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) and Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae) in maize. Two treatments were used: plants with silicon amendment (dosage of 1.000 kg ha-1) and plants cultivated without silicon. Recently emerged moths were released in acrylic cages (1 couple/cage for S. frugiperda and 3 couples/cage for D. saccharalis) containing two maize plants, one with and one without silicon, in a total of 12 replications (cages) per species. The number of eggs in each plant was counted 72 hours after releasing the moths. The plants with silicon amendment presented fewer eggs when compared with those without silicon, with a reduction of approximately 80% to S. frugiperda and 50% to D. saccharalis. These results show that silicon amendment in maize reduces the oviposition preference of the moths of S. frugiperda and D. saccharalis.