Repelência e atividade inseticida de pós vegetais sobre Zabrotes subfasciatus Boheman em feijão-fava armazenado

Abstract

Palavras-chave: plantas inseticidas, manejo alternativo, caruncho, Phaseolus lunatusABSTRACT: Repellency and insecticidal activity of plant powders on Zabrotes subfasciatus (Boh.) on stored lima beans. The purpose of this research was to evaluate the insecticidal potential of Piper nigrum L., Ruta graveolens L., Laurus nobilis L., Syzygium aromaticum Merr. & L.M.Perry., Chenopodium ambrosioides L., Piper tuberculatum Jaqc., Tagetes erecta L., Cymbopogon nardus L. and Melissa officinalis L. against Zabrotes subfasciatus by free choice, in which, by means of a circular arena, insects had a choice, treatments with or without powder and no choice tests, where insects were confined for five days in a container containing ten grains of lima beans with 0.3 g of powder to be tested. It was observed that some plants have killed the insect while others just repelled the insect, causing no harm to it. Also, one of the studied plants repelled and killed the insects (S. aromaticum, C. ambrosioides and P. tuberculatum). We can conclude that: P. nigrum, P. tuberculatum, S. aromaticum e C. ambrosioides are toxic to the Z. subfasciatus, causing its death. L. nobilis, T. erecta e C. nardus do not present any toxic effect over Z. subfasciatus. C. ambrosioides, S. aromaticum e C. nardus are repellent to Z. subfasciatus. P. nigrum, P. tuberculatum e T. erecta are neutral and M. officinalis have presented no effects over Z. subfasciatus in relation to the parameters evaluated. INTRODUÇÃOO gorgulho Zabrotes subfasciatus é a principal praga dos grãos ou sementes de feijão-fava (Phaseolus lunatus Linnaeus) durante o armazenamento, causando-lhes danos qualitativos e quantitativos. O controle químico se constitui na principal estratégia de manejo das pragas de grãos armazenados e, seu uso frequente tem provocado o surgimento de populações de insetos resistentes