Efeito subletal de extratos aquosos de Trichilia spp. sobre o desenvolvimento de Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) em milho

Abstract

-Among the new alternatives to pest control according to IPM systems, insecticide plants are an important tool because they reduce the use of synthetic insecticides, so preserving human health and the environment. The activity of aqueous extracts of leaves and twigs from six Trichilia species (T. casaretti, T. catigua, T. clausseni, T. elegans, T. pallens and T. pallida) was evaluated on Spodoptera frugiperda (J.E. Smith) development in laboratory conditions. Maize leaves immerged in each extract 1% (weight/volume) were dried and then provided to the first instar larvae. The effect of the extracts on survival, duration and weight of larval and pupal period was evaluated. The extracts from twigs of T. pallida and leaves of T. pallens were more efficient although the extracts from leaves of T. pallida, T. catigua, T. casaretti and T. elegans and twigs of T. clausseni and T. pallens also have affected the insect development.KEY WORDS: Insecta, fall armyworm, Meliaceae, botanical insecticide RESUMO -Na busca de alternativas para o manejo de pragas, as plantas inseticidas apresentam-se como ferramenta promissora, pois podem reduzir o uso de inseticidas sintéticos, amenizando os impactos prejudiciais ao homem e ao ambiente. Neste trabalho, foi avaliado o efeito de extratos aquosos de ramos e folhas de seis espécies de Trichilia

Effect of extracts of Trichilia silvatica C. DC., on development and reproduction parameters of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

“…Maroneze and Gallegos (2009) also found no negative effects of M. azedarach on the duration and viability of the pupal stage of S. frugiperda. The results concur well with those obtained by Bogorni and Vendramim (2005); Vendramim (1996, 1997), working with the Trichilia species, also found no negative effect of the extracts on the pupal stage of S. frugiperda. The biomass of the pupae was reduced (104.00±6.95 mg) in the LTS treatment when compared with the control (198.80±2.67 mg).…”

“…Such results have to confirm the insecticidal activity of this genus ever reported for S. frugiperda and other insects (Bogorni and Vendramim, 2003;Bogorni and Vendramim, 2005;Conceschi et al, 2011;Cunha et al, 2006;2008;Mikolajczak and Reed, 1987;Nebo et al, 2010;Roel et al, 2000b;Thomazini et al, 2000;Wheeler and Isman, 2000). Reports regarding the biological activities of the substances and / or extracts from plants of this genus, such as "antifeedant" and insecticidal properties, comparable to azadirachtin are available (Bogorni and Vendramim, 2005;Cunha et al, 2006;Mikolajczak and Reed, 1987). The LTS was found to affect not only the survival of S. frugiperda, but also other biological characteristics, such as the prolonged duration of the larval phase (20.34±0.49 days) when compared with the control (16.57±0.13 days).…”

“…This could be related to the presence of the compounds that interfered in metamorphosis, not only causing mortality but also hindering the development of the surviving larvae (Bogorni and Vendramim, 2005). The Trichilia T. pallens, T. casaretti and Trichilia pallida leaves and T. pallid branches also induced significant lengthening of the larval stage of S. frugiperda (Bogorni and Vendramim, 2005). The prolonged stage of the larval may be associated with the effect antifeedant reported in the Freitas, 2013 Figure 3.…”

“…The LTS was found to affect not only the survival of S. frugiperda, but also other biological characteristics, such as the prolonged duration of the larval phase (20.34±0.49 days) when compared with the control (16.57±0.13 days). This could be related to the presence of the compounds that interfered in metamorphosis, not only causing mortality but also hindering the development of the surviving larvae (Bogorni and Vendramim, 2005). The Trichilia T. pallens, T. casaretti and Trichilia pallida leaves and T. pallid branches also induced significant lengthening of the larval stage of S. frugiperda (Bogorni and Vendramim, 2005).…”

Bioatividade de moléculas isoladas de Trichilia pallida Swartz (Meliaceae) sobre Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)

“…Ao se avaliarem os resultados, é conveniente se considerar em trabalhos futuros um maior número de indivíduos a fi m de que a variabilidade observada seja minimizada. Similarmente, Bogorni & Vendramim (2005), ao avaliarem o efeito de extratos aquosos de folhas e ramos de várias espécies de Trichilia spp., observaram grande variação para o percentual de adultos de S. frugiperda deformados, sem constatar, no entanto, a ocorrência de diferenças signifi cativas para esse parâmetro.…”