Effects of synthesized tannin on the growth and survival of a generalist herbivorous insect, the common cutworm, Spodoptera litura Fabricius (Lepidoptera: Noctuidae).

Corrêa

et al. 2014

Chilean J. Agric. Res.

Fall armyworm, Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae) is the main pest of maize, besides attacking sorghum and cotton crops. The control of this pest has been accomplished mainly with the use of synthetic insecticides but, due to the growing concern about the environment and food quality, phenolic compounds have shown their potential for the biological control of this insect. Thus, the objective of the present study was to evaluate the efficiency of the extract of jabuticabeira, Myrciaria cauliflora [Mart.] O. Berg (Myrtaceae) fruit skin flour in the control of S. frugiperda. Skins of M. cauliflora Sabará genotype were dried at 45 °C in a forced air oven. In order to obtain the extract, 1.0 g flour was mixed with 10 mL acetone: water solution (7:3 v/v). Forty-eight-hour-old S. frugiperda caterpillars were placed in glass tubes with an artificial diet containing the extract at concentrations of 0, 250, 500, 1000, and 2000 mg L -1 . The extract, in which the phenolic compounds gallic acid, gallocatechin, catechin, epicatechin, ellagic acid, and salicylic acid were identified at a concentration of 2000 mg L -1 , in average, increased mortality rates by 150% in the larval stage, duration of larval stages by 60%, and pupal by 17%, and decreased amount of females by 55%. On the other hand, the extract at 1000 mg L -1 only increased duration of larval period by 24%. It was concluded that the extract is harmful to this insect, probably due to the presence of phenolic compounds.

Section: Resultsmentioning

confidence: 99%

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

Corrêa

et al. 2014

Chilean J. Agric. Res.

“…A presença de taninos é evidência da atividade antialimentar contra insetos. Assim, Nomura & Itioka (2002) A fração proveniente de P. dubium prolongou a duração das fases larval e pupal de S. frugiperda, além de causar redução no peso e na percentagem de sobrevivência desse inseto na fase pupal (Tabela 3). O alongamento da fase larval observado para as lagartas tratadas com P. dubium possivelmente se deu em função da redução na ingestão de alimentos; assim foi necessário que essas lagartas permanecessem se alimentando por um maior período de tempo antes de atingirem a fase de pupa.…”

Section: Resultsunclassified

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

et al. 2010

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...

“…They are present in high contents (frequently between 5-40% dry weight) (Meyer andKarasov 1989, Adams et al 2009) and thus represent a high initial investment cost (Coley et al 1985). Their effects are the result of the tissue content (Feeny 1992, Nomura andItioka 2002), acting mainly by reducing digestibility rather than through direct toxicity (Bernays 1991, Eichhorn et al 2007). They are effective against a broad herbivore spectrum including specialist herbivores (Beck and Schoonhoven 1980, Coley et al 1985, Bernays and Chapman 1994.…”

Section: Introductionmentioning

confidence: 99%

Lower P contents and more widespread terpene presence in old Bornean than in young Hawaiian tropical plant species guilds

et al. 2011

Abstract. Leaf elemental and secondary metabolite contents and morphological traits are important measures of time-dependent ecosystem changes. We aimed to test whether plants from older tropical forests have lower nutrient contents and different elemental stoichiometry than plants from younger ecosystems (''soil age'' hypothesis) and whether they had different contents of carbon based secondary compounds (CBSC) and morphological traits as a result of a longer evolution under tropical conditions. We conducted a phylogeny-independent study of the foliar chemical and structural traits in two sets of 86 species each measured in two different-aged tropical forests, a young soil forest in Hawaii and an old soil forest in Borneo. The leaf contents of nutrients and micronutrients tended to be higher in Hawaii than in Borneo but leaf N:P content ratio was not different. The ''soil age'' hypothesis was thus only partially supported by the results indicating that several other factors influence plant elemental content. Total phenolic content was twice larger in Hawaiian than in Bornean plant species. Terpene contents were not different in terpene-containing species but the percentage of species containing terpenes was much higher in Borneo (97%) than in Hawaii (34%) suggesting that the longer time of evolution in Borneo has allowed a more widespread development of very diverse defensive, allelopatic and information relationships of plants with specialist herbivores and other plants. Principal component analyses separated Hawaii and Borneo species on the basis of leaf elemental composition, total phenolics and terpene contents and leaf dry mass per area (LMA). The results collectively support the ''leaf economic spectrum'' and ''carbon excess'' paradigms because in both sets of species and also in the combined set of Borneo and Hawaiian species, there are negative relationships of N content with LMA and total phenolics. The results suggest thus that changes throughout time in N and P availability can be important but do not explain all the variability underlying the evolutionary changes in leaf chemistry and structure in these tropical forests. Other factors determining species biogeochemical niche such as K, Mg or S elemental stoichiometry, leaf economic traits and changes in plant defence and communication strategy are also likely to be involved.