Efeito de Bacillus thuringiensis Berliner e inseticidas químicos sobre a traça-das-crucíferas, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) e seus parasitóides

Abstract

Effects of Bacillus thuringiensis Berliner and Chemical Insecticides on Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) and its Parasitoids ABSTRACT-Three biopesticides based on Bacillus thuringiensis (Dipel, Florbac and Biobit), and two chemical insecticides (deltamethrin and abamectin) were evaluated in field trials against Plutella xylostella (L.) and its parasitoids in Brazil. Plots treated with Florbac, Biobit and abamectin produced 100% marketable cabbages. Dipel and deltamethrin also resulted in acceptable control (85% yield). In the control plot, 97.2% of the yield was lost. The rate of parasitism on the plots treated with biopesticides was between 35.7 and 60.5%, in the control was 42.9% and in those treated with chemical insecticides was 9.0 and 25.8 %. These results indicate that the biopesticides had no adverse effect on the parasitoids, in contrast to the classic chemical products.

New records of natural enemies of Plutella xylostella (L.) (Lepidoptera: Plutellidae) in Pernambuco, Brazil

“…Among the parasitoids found in this study, C. pseudofulvovariegata and C. plutellae were previously found in Brasília, DF by Guilloux et al (2003) and Monnerat et al (2000), respectively. Therefore, this is only the second time they are reported in Brazil parasitizing DBM.…”

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

“…Unfortunately, this pest control management resulted in harmful outcomes such as the selection of resistant populations of insect pests, compromising the efficiency of control and forcing farmers to use increasingly high doses of pesticides [2][3][4]. Moreover, these chemical insecticides have harmful effects on human health and wildlife, leaving residues in food and the environment [2,3].…”

“…Among the viable alternatives for the replacement of these synthetic pesticides, entomopathogenic biological agents show potential for use in biological control programs and integrated production, because they leave few human side effects and have low impact on natural enemies and the environment [3,5,6]. In this context, Bacillus thuringiensis (Bt), a gram-positive, rod-shaped, spore-forming bacterium, is the most important biopesticide sold worldwide [7,8], having been used for over 40 years by organic farmers who spray it as a foliar insecticide [7,9].…”

Efeito de tratamentos químicos alternativos no controle de <em>Diaphania</em> spp. (Lepidoptera: Crambidae) em pepino

“…O óleo de nim e os extratos vegetais de folhas e sementes de cinamomo e de folhas de pessegueiro bravo + pimenteira não reduziram significativamente os danos das brocas-dascucurbitáceas em relação à testemunha (Tabela 2). A utilização de inseticidas biológicos formulados com a bactéria B. thuringiesis é uma técnica empregada com sucesso para o controle de muitas espécies de lepidópteros (Dias, 1992 O B. thuringiensis apresenta boa eficiência de controle para insetos como Plutella xylostella (L.) (Lepidoptera: Plutellidae), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) e Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) (França et al, 1985;Haji et al 1995;Monnerat et al, 2000). Entretanto, existem diferenças no grau de eficiência para diferentes variedades da bactéria e, com produtos elaborados com a mesma variedade, em função de aspectos da formulação dos produtos (Monnerat et al, 2000).…”

“…A utilização de inseticidas biológicos formulados com a bactéria B. thuringiesis é uma técnica empregada com sucesso para o controle de muitas espécies de lepidópteros (Dias, 1992 O B. thuringiensis apresenta boa eficiência de controle para insetos como Plutella xylostella (L.) (Lepidoptera: Plutellidae), Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) e Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) (França et al, 1985;Haji et al 1995;Monnerat et al, 2000). Entretanto, existem diferenças no grau de eficiência para diferentes variedades da bactéria e, com produtos elaborados com a mesma variedade, em função de aspectos da formulação dos produtos (Monnerat et al, 2000). Essa mesma situação pode vir a ocorrer com as brocas das cucurbitáceas, havendo a necessidade de avaliações envolvendo outros sorotipos e formulações do B. thuringiesis, para a disponibilização de outros produtos para o controle de D. nitidalis e D. hyalinata.…”