Extratos de Ocimum campechianum para controle de lagartas Ascia monuste orseis

Ascia monuste orseis Godart, destaca-se como inseto praga em cultivos de brássicas. Entre as estratégias de controle, o uso de pesticidas é a mais utilizada, porém com uso contínuo e indiscriminado ocasionam problemas para o meio ambiente e para a saúde humana. Os inseticidas botânicos são alternativa promissora. Assim, este trabalho investigou o estímulo-resposta do extrato bruto hidroalcoólico de Ocimum campechianum Mill. (Lamiaceae) e de sua fração diclorometano (DCM) sobre a toxicidade, preferência alimentar e o desenvolvimento de lagartas de A. monuste orseis. Avaliou-se a toxicidade, a preferência alimentar (teste com e sem chance de escolha) e o desenvolvimento das lagartas até a fase pupal. Nos testes de desenvolvimento e preferência alimentar, utilizou-se as concentrações subletais definidas a partir do teste de toxicidade, 10,00 e 2,50 mg mL-1, para o “extrato bruto” e sua “fração DCM”, respectivamente. Utilizou-se oito repetições com cinco lagartas. Observou-se que o extrato bruto e a fração DCM de O. campechianum foram tóxicos e reduziram a alimentação das lagartas de três dias (dias após a eclosão), apresentando CL50 de 52,95 e 20,90 mg mL-1, respectivamente. Entretanto, não afetaram o desenvolvimento do inseto. Portanto, o extrato bruto e sua fração DCM de O. campechianum apresentam potencial para uso no controle alternativo de lagartas de A. monuste orseis

Du libre accès à l'accès restreint aux écoles anglaises du Québec

In this article, the author gives a historical account of the different laws enacted by the National Assembly in order to enhance the status of the French language at administrative levels as well as among the province's résidants themselves. The schools, being vehicles of social and cultural influence, were included. Laws 63 and 22 were little more than tentative, hesitant sallies into the linguistic battle confronting the province and its minority groups. Law 101 provided a more coherent line of reasoning in deciding Quebec's language policies. Nevertheless, it is contested by some groups on constitutional grounds

INSETICIDAL OILS FROM AMAZON PLANTS IN CONTROL OF FALL ARMYWORM

The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third-instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae), Orbignya phalerata (Arecaceae), and Carapa guianensis (Meliaceae) displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v). Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests

Hydroalcoholic plant extracts from the southwest Amazon for the alternative control of fall armyworms

This study aimed to screen plant species from the Amazon region for the potential to be used in the integrated management of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). For this purpose, the efficiency of the hydroalcoholic extracts of 15 plant species from the Amazon region was evaluated. The extracts were obtained from plant leaves, bark, or vines. The efficiency of the extracts (30 mg-mL-1) was evaluated on eggs and third instar larvae of S. frugiperda. A range of reactions of the fall armyworm to the hydroalcoholic extracts was observed. The extract obtainedfrom the bark of Calycophyllum spruceanum (Benth.) Hook. f. ex K. Schum. presented the highest efficiency against the eggs, whereas the extract obtained from the leaves of Bauhinia forficata Link was most efficient against the larvae. These findings are essential for the management offall armyworms because the deleterious effects in the initial stages of S. frugiperda development significantly reduce maize production. In conclusion, the extracts of C. spruceanum and B. forficata were more efficient for eggs and larvae of the fall armyworm, respectively.Esta investigación tiene el objetivo de hacer una selección de especies vegetales que son propias de la región Amazónica con potencial de uso en el manejo integrado de la oruga militar tardía Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Para tal, fue evaluado la eficiencia de extractos hidroalcohólicos de 15 especies vegetales que se son de la región. Los extractos fueron producidos a partir de las hojas, o de la cáscara, o de liana de las plantas. La eficiencia de los extractos (30 mg.mL-1) fue evaluada sobre huevos y larvas de 3° instar de S. frugiperda. Se constató una variación de respuesta de la oruga militar tardía entre los extractos hidroalcohólicos. El extracto de la cáscara de Calycophyllum spruceanum (Benth.) Hook. f. ex K. Schum. presentó mayor eficiencia en los huevos, y el extracto de las hojas de Bauhinia forficata Link presentó mayor eficiencia en las larvas. Estos resultados son fundamentales para el manejo de la oruga militar tardía, toda vez que, los efectos nocivos reducen las pérdidas en la producción de maíz en las primeras fases del desarrollo del S. frugiperda. Se concluye que los extractos de C. spruceanum y B. forficata fueron los más eficientes para los huevos y larvas de la oruga militar tardía