integração da resistência de plantas e predação por chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) Para o manejo de schizaphis graminum (Rondani) (Hemiptera: Aphididae) em Sorgo

Abstract

The integration of plant resistance and biological control agent can be a viable alternativeto the management of the greenbug, Schizaphis graminum (Rondani), on sorghum. Experimentswere conducted to evaluate the effect of four sorghum genotypes: GR 11111 and TX 430 x GR 111(resistants), GB 3B (moderately resistant), and BR 007B (susceptible), on the biological control of S.graminum by the predator lacewing, Chrysoperla externa (Hagen). Different levels of infestation, inpresence or absence of the predator were studied in greenhouse, and the viability of S. graminumcontrol was evaluated under field conditions. The effect of the predator was observed 25 days afterinfestation, resulting in higher percentage of plant growth and lower damage. Damage was lower inresistant genotypes and increased with higher levels of infestation, being low in presence of predator C.externa. In field conditions, plant damage was reduced in 83%, when the genotype TX 430 x GR 111was used in association with C. externa.