6 research outputs found
Ecologically Acceptable usage of Derivatives of Essential Oil of Sweet Basil, Ocimum basilicum,
Ethanol solutions of five fractions obtained from essential oil of sweet basil Ocimum basilicum L. (Lamiales: Lamiaceae) (F1–F5) were tested for their antifeedant properties against 2(nd) instar gypsy moth larvae, Lymantria dispar L. (Lepidoptera: Lymantriidae), in laboratory non-choice and feeding-choice experiments. Prior to bioassays, the chemical composition of each fraction was determined by gas chromatography analyses. Significant larval deterrence from feeding was achieved by application of tested solutions to fresh leaves of the host plant. The most effective were were F1 (0.5%), F4 (0.05, 0.1, and 0.5%), and F5 (0.1 and 0.5%), which provided an antifeedant index > 80% after five days. A low rate of larval mortality was observed in no-choice bioassay. In situ screening of chlorophyll fluorescence as an indicator of plant stress level (assessed by the induced fluorometry) confirmed that the tested compounds did not cause alternations in the photosynthetic efficiency of treated leaves
Eficiência de produtos vegetais no controle da lagarta-do-cartucho-do-milho Spodoptera frugiperda (J.E.Smith, 1797) (Lepidoptera: Noctuidae) Efficience of extracts of plantas in control of fall armyworm in corn Spodoptera frugiperda (J.E.Smith, 1797) (Lepidoptera: Noctuidae)
O presente trabalho teve por objetivo avaliar a eficiência de produtos vegetais no controle de Spodoptera frugiperda (J.E.Smith, 1797) na cultura do milho. Os experimentos foram instalados, nos anos de 2002 e 2004, com a pulverização dos produtos vegetais em cinco tratamentos, e quatro repetições. No ano de 2002, os produtos testados foram: Azadirachta indica A. Juss. (extrato aquoso 2%), e óleo a 1%; Melia azedarach L. (extrato aquoso 2%); Quassia amara L. (extrato aquoso 2%); óleo de nim, Azadirachta indica 1 e 2%. No ano de 2004, os produtos testados foram: A. indica (extrato aquoso 5%), e óleo a 2%, M. azedarach (extrato aquoso 5%), Trichilia pallida Sw. (extrato aquoso 5%). As avaliações, porcentagem de infestação da lagarta-do-cartucho por parcela, foram efetuadas aos três, sete e dez dias após a pulverização dos extratos. Conclui-se que extratos aquosos das plantas A. indica 2%, T.pallida 5%, Q. amara 2% e M. azedarach 2% e 5% e óleo de A. indica 1% e 2% com adição de tenso ativo não iônico, não possuem eficiência necessária como único método de controle da largarta-do-cartucho S. frugiperda em condições de campo. Os produtos começam a afetar o desenvolvimento da lagarta após alguns dias da ingestão das folhas pulverizadas, observado na avaliação efetuada aos sete dias após a aplicação dos extratos.<br>The objective of this work was to study the efficiency of vegetable pesticides in the control of Spodoptera frugiperda (J.E.Smith, 1797) in corn culture. The experiments were installed, in the years of 2002 and 2004, with the spraying of the vegetable products in five treatments, and four repetitions. In the year of 2002 the tested products were: Azadirachta indica A. Juss (aqueous extract 2%), and oil at 1%; Melia azedarach L. (aqueous extract 2%); Quassia amara L. (aqueous extract 2%); nim oil, Azadirachta indica 1 and 2%. In the year of 2004 the tested products were: A. indica (aqueous extract 5%), and oil at 2%, M. azedarach (aqueous extract 5%), Trichilia pallida Sw. (aqueous extract 5%). The evaluations like percentage of infestation of the fall armyworm per plot, were made three, seven and ten days after the extracts application respectively. It was possible to verify that aqueous extracts of the plants A. indica 2%, T. pallida 5%, Q. amara 2% and M. azedarach 2% and 5% and A. indica oil 1% and 2% with addition of non ionic active tense, don't possess necessary efficiency as the only control method of the fall armyworm S. frugiperda in field conditions. The products begin to affect the development of fall armyworms some days after the ingestion of the powdered leaves, observed in the seven days after the extracts application