Atividade inseticida do óleo essencial de Tanaecium nocturnum (Barb. Rodr.) Bur. & K. Shum (Bignoneaceae) sobre Sitophilus zeamais Motsch. (Coleoptera: Curculionidae)

Abstract

RESUMOO óleo essencial extraído de folhas frescas de Tanaecium nocturnum (Barb. Rodr.) Bur.& K. Shum por destilação de arraste a vapor foi avaliado quanto à toxicidade a Sitophilus zeamais Motsch., principal praga do milho armazenado. Papel de filtro e grãos de milho foram impregnados pelo óleo para se avaliar o efeito por via de contato (papel-filtro) e fumigação, respectivamente. Para avaliação do efeito da aplicação tópica 0,5 µl das diferentes concentrações do óleo foram aplicadas em adultos do inseto. A partir de uma ampla faixa de concentrações, foram determinadas as mais promissoras para os bioensaios definitivos. Na determinação das dose/concentrações-letais (DL 50 e CL 50 ) foi utilizada a análise de Probit, realizando-se também, uma análise de regressão linear conjunta de todos os dados de mortalidade. O óleo de T. nocturnum foi considerado tóxico para S. zeamais baseado nos seguintes valores: CL 50 de 14,1 ng.cm -2 e CL 50 de 1.321,6 ng.g -1 de grãos para os efeitos de contacto (papel-filtro) e fumigação, respectivamente, e DL 50 de 14,7 µg.mg -1 de inseto para efeito tópico. Porcentagens de mortalidade próximas a 100 % foram obtidas nas concentrações de: 2 e 5 % (m/v) (contato), 3 4, e 5 % (m/v) (fumigação) e 10 % (m/v) para o efeito de aplicação tópica. O presente estudo mostrou que o ácido cianídrico, liberado do óleo essencial de T. nocturnum por hidrólise, pode ter atividade inseticida para S. zeamais e que concentrações acima de 4 % (m/v) são promissoras no controle do inseto. . Filter paper and maize grains impregnation was employed, for contact and fumigant toxicity effect studies, respectively. For topical effect studies, aliquots of 0,5 µl of the diluted oil applied to adults insects. We used a broad range of concentrations to be used for establish the most promising concentrations. Probit analysis was employed in analyzing the dose/ concentration-mortality response (LD 50 and LC 50 ). Linear regression analysis was applied in mortality of maize weevil adults. The toxicity (LC 50 ) T. nocturnum oil to S. zeamais was of 14.1 ng.cm -2 and LC 50 of 1,321.6 ng.g -1 of the grains for contact and fumigant effects, respectively, and LD 50 of 14.7 µg.mg -1 of the insect for topical application. For contact and fumigant effects, the mortality rate was nearly 100 % at oil concentrations of 2 % and 5 % (m/v), and 4 % and 5 % (m/v), respectively. For contact, fumigant, and topical effects, the mortality rate was nearly 100 % at oil concentrations of 2 % and 5 % (m/v); 4 % and 5 % (m/v) and 10 % (m/v) respectively. The current study shows that cyanidric acid, liberated from the essential oil of the T. nocturnum, posses fumigant insecticidal effect on S. zeamais in concentrations more than 4 % (m/v) were promises.

Extraction Yield, Chemical Composition, Preliminary Toxicity of Bignonia nocturna (Bignoniaceae) Essential Oil and in Silico Evaluation of the Interaction

“…No volatiles were obtained from the fresh stems. There have been other reports on benzaldehyde being the major compound in the Bignonia nocturna [cited as Tanaecium nocturnum ] essential oil [29,30] …”

Evaluation of chemical composition and antiedematogenic activity of the essential oil of Hyptis martiusii Benth

“…Many cases of dermatitis and allergic reactions were caused by treatments that involve the use of concentrated essential oils (Veiga Junior et al, 2005). An example of plant species that fits this context is the essential oil Tanaecium nocturnum , which at certain concentrations can cause contact dermatitis (Fazolin et al, 2007). Similarly, the essential oil from Lippia sidoides and its isolated constituent, thymol, presents a pro-inflammatory effect in chronic topic models (Veras et al, 2013) and therefore a significant edematogenic activity.…”

Effiiency of the Essential Oil of Porophyllum linaria (Asteraceae) a Mexican Endemic Plant Against Sitophilus zeamais (Coleoptera: Curculionidae)

“…The Selection Index test showed that the concentration of 800 ppm provokes 100% of repellent effect, suggesting that the repellent effect of P. linaria may be determined by the presence of secondary metabolites and volatile substances present in the plant. In addition, the layer of essential oil and its chemical components that cover the grains after treatment seems to have a certain influence on the insect behavior ( Lee et al 2004 , Jayasekara et al 2005 , Asawalam et al 2006 , Fazolin et al 2007 , Moreira et al 2007 ); when these substances are detected by insects, they exert effect on their behavior and cause migration to other places ( Pérez et al 2007 ). In another study, Jiménez et al (2012) analyzed the leaves and stems of P. tagetoides (syn.…”

“…After 20 min to evaporate the ethanol, 20 adults of 10–12 d old unsexed were placed ( Fazolin et al 2007 ). The weevil mortality was counted to 1, 5, 10, and 15 d. We established a negative control without application of essential oil with 100 µL acetone ( Lagunes and Rodríguez 1989 , González et al 2009 , Oliveira et al 2012 ) and piperonyl butoxide with deltamethrin as pyrethroid insecticide at 10 µL cm −2 (K-Obiol 2.5, Bayer México) was used as a positive control.…”