Insecticidal Activity of Aqueous Extracts of Plant Origin on Mahanarva spectabilis (Distant, 1909) (Hemiptera: Cercopidae)

The spittlebug Mahanarva spectabilis (Distant, 1909) is considered the main and most limiting pest of elephant grass (Pennisetum purpureum Schum.), has caused economic losses to Brazilian farmers. In this study, we evaluated insecticidal effects aqueous extracts garlic, rue, cinnamon, lemongrass, clove, star anise, eucalyptus, tobacco, thyme on M. nymphs. results indicated that tobacco extract was effective among all extracts, as it reached a mortality 76%. next anise cinnamon least effective. second stage tests, potential five concentrations extract. values LD50 LD90 calculated for were, respectively, 11.5% 33.3% 24 h after application, 9.2% 29.5% 48 application. We also different methods extraction, through comparative infusion decoction proved be equivalent those method extraction by ultrasound. conclude nine plant tested, only one recommended against spectabilis, showed activity, with better at concentration 25%, decoction.