ABSTRACT The effect of a crude extract of Annona crassiflora was evaluated on larvae of the soybean looper, Chrysodeixis includens (Lepidoptera: Noctuidae) in different stages of larval development. The extract was prepared with seeds of A. crassiflora fruits collected in the state of Mato Grosso, Brazil. The extract was diluted in water and solubilizer agent at the concentrations of 0.5, 1.0, 2.0, 4.0, and 8.0%; it was tested by ingestion of treated leaves and contact. The mortality rate of topically treated caterpillars of first, third, and fifth instars was significantly higher than that of the control group. For first instar caterpillars, mortality was observed within the first 24 h after application, while, for the remaining instars, it was... |