Efeito de frações tânicas sobre parâmetros biológicos e nutricionais de Spodoptera frugiperda (Lepidoptera: Noctuidae)

Abstract

RESUMOConduziu-se este trabalho, com o objetivo de quantificar taninos condensados presentes nas cascas do caule de Ochroma pyramidalis (Bombacaceae), Schinus terebinthifolius (Anacardiaceae), Enterolobium contortisiliquum (Fabaceae) e Peltophorum dubium (Fabaceae) e verificar o efeito de frações tânicas dessas espécies sobre parâmetros biológicos e nutricionais de S. frugiperda. A partir das cascas das espécies vegetais se prepararam extratos, dos quais alíquotas foram tomadas para a quantificação dos taninos. Em seguida, os extratos foram submetidos a fracionamento para a obtenção das frações tânicas, que foram incorporadas à dieta artificial e oferecidas para lagartas de S. frugiperda. Todas as espécies vegetais estudadas apresentaram taninos condensados, sendo que S. terebinthifolius apresentou menor quantidade desses compostos. A fração tânica de P. dubium causou redução no peso das lagartas e pupas, diminuição na sobrevivência de S. frugiperda durante as fases larval e pupal, e acarretou menor consumo alimentar, além de prolongar a duração das fases imaturas desse inseto. O tratamento com S. terebinthifolius causou redução na percentagem de sobrevivência, durante a fase de pupa. Pupas provenientes de lagartas que receberam tratamento com a fração de E. contortisiliquum tiveram aumento no seu período de desenvolvimento. Lagartas alimentadas com a fração proveniente de P. dubium apresentaram a menor taxa de crescimento relativo (RGR), menor eficiência de conversão do alimento digerido (ECD) e maior custo metabólico (CM). A digestibilidade aproximada (AD) foi maior para os tratamentos com as frações tânicas de P. dubium e S. terebinthifolius. Termos para indexação: Lagarta militar, taninos condensados, produtos naturais, controle. ABSTRACTThe objective of this study was to quantify condensed tannins present in the stem bark of Ochroma pyramidalis (Bombacaceae), Schinus terebinthifolius (Anacardiaceae), Enterolobium contortisiliquum (Fabaceae) and Peltophorum dubium (Fabaceae) and to verify the effect of tannic fractions of these species on biological and nutritional parameters of S. frugiperda. Extracts were prepared from the barks of the plant species and aliquots were taken from them to quantify the tannins. The extracts were then submitted to fractionation to obtain the tannic fractions, which ones were incorporated into an artificial diet and offered to the larvae of S. frugiperda. All the studied species showed condensed tannins, and S. terebinthifolius showed the lowest amount of these compounds. The tannin fraction of P. dubium caused a reduction in the weight of larvae and pupae, decreased the survival of S. frugiperda during the larval and pupal stages and led to a reduction of intake, beyond to extend the duration of immature stages of this insect. The treatment with S. terebinthifolius caused a reduction in the survival percentage during the pupal stage. Pupae from larvae that received the treatment with the fraction of E. contortisiliquum had an increase in its development period stage. Larvae fed...

Toxicity of the phenolic extract from jabuticabeira (Myrciaria cauliflora (Mart.) O. Berg) fruit skins on Spodoptera frugiperda

“…A longer duration of the larval stage is an advantage in field, since the insects will be prone to predators' attack for a longer time. This result confirms the ones found by Tirelli et al (2010), who also found effects of tannin fractions of the stem bark on this pest. It was observed that the treatment with 2000 mg L -1 of extract extended the pupal stage of S. frugiperda, while pupal weight was not reduced by any treatment ( Figure 2).…”

“…Gallo et al (2006) reported up to 86% mortality of S. frugiperda larvae when fed artificial diets containing phenolic compounds isolated from Vitex polygama Cham (Verbenaceae) and Siphoneugena densiflora Berg (Myrtaceae). Tirelli et al (2010) found an increase in the duration of larval and pupal stages of S. frugiperda due to the effect of tannins in the stem bark of several forest species, on, besides decrease of about 30% in pupal weight and 41% in larvae survival. Jabuticabeira (Myrciaria cauliflora [Mart.]…”

Bioactivity of ethanolic extracts of Euphorbia pulcherrima on Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

“…Similar type of results were presented by Sâmia (2013) using Copaifera langsdorffii aqueous extracts in 2nd instar S. frugiperda larvae, leading to reduced weight of feces excreted; the author states that this reduction may be related to food deterrence caused by some substance present in aqueous extracts, possibly enzyme inhibitors. Tirelli et al (2010) using tannic fractions of Schinus terebinthifolius have found a reduction in excreted feces in the control treatment, but these treatments did not decrease the food consumption.…”

Malpighia emarginata DC. bagasse acetone extract: Phenolic compounds and their effecton Spodoptera frugiperda(J.E. Smith) (Lepidoptera: Noctuidae)

“…According to Tirelli et al (2010) and Jadhav et al (2012), inhibition of larval growth and duration of the pre-pupal and pupal stages have already been related to the activity of phenolic compounds, especially tannins and flavonoids, which reduce the nutritional value but create the antifeedant effect in food. Alves et al (2014) studied the effects of acetone extract from jabuticaba (Myrciaria cauliflora [Mart.]…”

“…Therefore, the search for new products with insecticidal action against this pest is of great importance. The potential of the products of plant metabolism to control insect pests has been evaluated (Tirelli et al, 2010;Alves et al, 2011;Santos et al, 2013;Alves et al, 2014). Secondary metabolites are involved in plant defense against herbivores and as such have the potential to be used in the control of insect infestations.…”