Composição química e toxicidade de óleos essenciais para o pulgão-verde Schizaphis graminum (Rondani, 1852)

Abstract

ABSTRACT:The aim of this study was to assess the chemical composition of essential oils of Illicum verum, Ageratum conyzoides, Piper hispidinervum and Ocotea odorífera, as well as their toxicity to the green-aphid Schizaphis graminum. Compound identification was carried out with gas chromatography + mass spectrometry, and quantification with gas chromatography + flame ionization detector, both with DB5 column. The hydrodistillation process promoted oil yield of 3.81% for I. verum; 0.46% for A. conyzoides; 2.85 % for P. hispidinervum; and 0.68 % for O. odorífera. The major components from the oils of A. conyzoides was precocene (87.0%) and (E)-caryophyllene (7.1%); (E)-anethol (90.4%), limonene (2.6%) and methyl-chavicol (1.3%) for I. verum; methyleugenol (81.2%) and safrole (10.6%) for O. odorifera; and safrole (82.5%) and α-terpinolene (13.4%) for P. hispidinervum. The acute toxicity test (24 hours) performed by contact in sorghum leaves or contaminated filter-paper showed that the higher toxicity occur with essential oils of A. conyzoides, with LC 50 of 7.01 and 7.01 µg oil/cm 2 , respectively; followed by O. odorifera, with LC 50 of 17.10 and 66.70 µg oil/cm 2 , respectively; I. verum, with LC 50 of 66.40 and 65.40 µg oil/cm 2 , respectively; and low toxicity was observed for the P. hispidinervum essential oil, with LC 50 of 64.00 and 143.00 oil/cm 2 , respectively. With the results obtained in this research, we can state that the use of these essential oils can be a new tool in integrated pest management.

Anti-Ehrlichia properties of the essential oil of Ageratum conyzoides L. and its interaction with doxycycline

“…Castro et al (2004) evaluated 5 different types of accessions of A. conyzoides and obtained contents between 0.48% and 0.70%. Other authors including Lima et al (2014) and Barros et al (2016) found yields of 0.46% and 0.08%, respectively. This is mainly due to climate, incident solar radiation, relative humidity, and different soil type as previously reported.…”

Socioeconomic Motivations for Conservation and Sustainable Use of the Caatinga Biome

“…Segundo Kim et al (1995), alguns tem a capacidade de inibir bactérias de origem alimentar e prolongar a vida de prateleira de alimentos processados. Além disso, estudos apontam que essas substâncias possuem efeito antifúngico (Machado et al, 2013), anti--inflamatórios, antinociceptivo e antiespasmódico (Daniel et al, 2009;Adorjan & Buchbauer, 2010;Pinho et al, 2012), atividades antitumoral (Wang et al, 2012;Quassinti et al, 2013) e inseticida (Lima et al, 2014). Portanto, é necessária a implantação de políticas públicas de conscientização, voltadas para o melhor manejo do extrativismo sustentável desse bioma, com vistas à preservação.…”