Toxicity of extracts and isobutyl amides from Piper tuberculatum: potent compounds with potential for the control of the velvetbean caterpillar, Anticarsia gemmatalis - Navickiene, Hosana Maria Debonsi; Miranda, José Ednilson; De Bortoli, Sérgio Antônio; Kato, Massuo Jorge; Bolzani, Vanderlan da Silva; Furlan, Maysa (Pest Management Science, 2007)