Toxicidade por fumigação, contato e ingestão de óleos essenciais para Sitophilus zeamais Motschulsky, 1885 (Coleoptera: Curculionidae)

Abstract

RESUMOA espécie Sitophilus zeamais é uma das principais pragas do milho armazenado no Brasil. O controle é feito, comumente, utilizando-se medidas de higienização e limpeza, bem como inseticidas sintéticos fumigantes e protetores. A busca por produtos menos tóxicos, biodegradáveis e seguros do ponto de vista ecológico, é muito bem aceita pela sociedade. Assim, os objetivos do presente trabalho foram testar a toxicidade de contato e ingestão e fumigante de óleos essenciais e do composto orgânico natural eugenol para adultos de S. zeamais. Termos para indexação: Gorgulho do milho, bioatividade, plantas inseticidas, concentrações letais. ABSTRACTThe Sitophilus zeamais species is a major pest of stored maize in Brazil. The control is made, usually, using measures of hygiene and cleanliness, synthetic insecticides and fumigant protectors. The search for less toxic products, biodegradable and safe from an ecological point of view is very well accepted by society. The objective of this study was to test the toxicity by contact and ingestion and fumigant of essential oils and eugenol natural organic compound for adults of S. zeamais. The values of LC 50 in oil from leaves of Piper hispidinervum, Eugenia uniflora, Cinnamomum zeylanicum, P. marginatum, Schinus terebinthifolius, Melaleuca leucadendron, green fruits of S. terebinthifolius and eugenol compound in tests of contact and ingestion were estimated at 1.0; 11.6, 14.2, 21.1, 57.7, 75.8, 98.8 and 14.8 L/40 g maize, respectively. The toxicity ratios (TR) ranged from 1.3 to 98.8. In the fumigation of adults, the lethal concentrations ranged from 0.53 to 94.7 L/L air, in the following order of toxicity: P. hispidinervum > P. aduncum > S. terebinthifolius > green fruits of S. terebinthifolius > P. marginatum > eugenol, and the TR ranged from 2.0 to 178.7.

Insecticidal activity of Laurelia sempervirens (Ruiz & Pav.) Tul. essential oil against Sitophilus zeamais Motschulsky

“…), Piper marginatum Jacq. (Coitinho et al, 2011) (Piperaceae), Schinus terebinthifolia Raddi (Anacardiaceae), and Melaleuca leucandendra (L.) L. (Myrtaceae) (Coitinho et al, 2011) with concentrations between 2.8 μL 40 g -1 essential oil showed higher toxicity. Perhaps because of the temperature, the essential oil of L. sempervirens did not reach the 90% of dead.…”

Toxicity of essential oils of Piper marginatum Jacq. against Tetranychus urticae Koch and Neoseiulus californicus (McGregor)

“…the mosquito Aedes aegypti and also serve as a deterrent to oviposition (Autran et al, 2009). The insecticidal activity of P. marginatum oil has been reported for other arthropods, such as Solenopsis saevissima (Souto et al, 2012), Tenebrio molitor (Fazolin et al, 2007), Sitophilus zeamais (Estrela et al, 2006;Coitinho et al, 2011), Tyrophagus putrescentiae and Suidasia pontifica (Assis et al, 2011). However, no previous study has evaluated the acaricidal action of P. marginatum oil on T. urticae and its natural enemy, N. californicus.…”

Bioactivity of Peumus boldus Molina, Laurelia sempervirens (Ruiz & Pav.) Tul. and Laureliopsis philippiana (Looser) Schodde (Monimiacea) essential oils against Sitophilus zeamais Motschulsky

“…It may cause a complete grain loss in only 6-mo (Coitinho et al, 2011). Its control is usually performed with synthetic insecticides, leading to important problems such as the presence of undesirable residues on food and development of resistance to insecticides as phosphine (Pimentel et al, 2009), organophosphates and pyrethroids .…”