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Jatropha curcas L. has been studied with the aim of attending the bioenergy demand in Brazil. In this study, the time of occurrence, the severity, and the control of powdery mildew and rust in a commercial crop were investigated. During the evaluation period, powdery mildew was first observed soon after the onset of the raining period in October. Rust was first observed in April. Metarhizium anisopliae. Azadirachta indica oil, J. curcas oil, and the fungicide triadimenol were efficient in controlling powdery mildew. None of these products nor potassium silicate did control rust. RESUMO Jatropha curcas L. tem sido estudada com o objetivo de atender a demanda por bioenergia no Brasil. Neste trabalho estudou-se a época de ocorrência, a severidade e o controle do oídio e da ferrugem numa lavoura comercial. Durante o período de avaliação, o oídio foi observado pela primeira vez logo após o início do período de chuvas em outubro. A ferrugem foi observada pela primeira vez em abril. Metarhizium anisopliae, óleo de Azadirachta indica, óleo de J. curcas e o fungicida triadimenol foram eficientes no controle do oídio. Nenhum desses produtos nem silicato de potássio controlaram a ferrugem.

This paper aimed to evaluate the direct and indirect effects of Bt cotton and no Bt cotton on the development and reproduction of the predator Podisus nigrispinus (Dallas). The experiments related to the direct and indirect effects on immature and adult stages of the predator were conducted, respectively, in greenhouse and laboratory of the Embrapa Agropecuaria Oeste in Dourados, Mato Grosso do Sul State, Brazil. To evaluate the indirect effects of Bt cotton and non-Bt, larvae of Spodoptera frugiperda (Smith) were fed with these plants and later offered to the predator. To evaluate the direct effect of the Bt cotton and non-Bt, the predator P. nigrispinus was kept in contact with these plants and fed with pupae of Tenebrio molitor (L.). The direct and indirect effects were evaluated by the biological parameters as follows: period of nymphal development, nymphal survival, and duration of pre-oviposition and oviposition periods and longevity of adults (females and males) of P. nigrispinus. It was observed higher period of second instar of P. nigrispinus in Bt cotton, when compared to the development in its isoline non-Bt. All other biological parameters evaluated, have no influence of the Bt cotton plants considering the direct and indirect effects.

The aim of this study was to evaluate the non-preference for oviposition Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) in cassava cultivars. The following cultivars were compared: Kiriris, N-25, Fecula Branca, IAC 90, M Ecu 72 and IAC 576, preference tests for oviposition were conducted, with a choice test in semi-field conditions. An adult double V. illudens was released in the leaves of cassava of their cultivars. Allowed to feeding and oviposition of these insects for 72 hours. We evaluated the number of eggs / female / leaf, the number of droppings / couple / sheet and the preference index for oviposition. The cultivar M Ecu 72 demonstrated to be highly resistant to cassava lace bug. This study showed that there are resistance mechanisms to V. illudens in cassava cultivars, which justifies the new studies on these cultivars in breeding programs, aiming to control this pest and identification of such mechanisms.

Helicoverpa armigera e uma praga recentemente identificada no Brasil ocasionando perdas significativas em varias culturas em varias regioes do pais. O controle biologico tem sido relatado como uma das alternativas promissoras para o manejo desta praga. O objetivo deste trabalho foi avaliar o parasitismo de pupas de H. armigera pelos parasitoides Tetrastichus howardi e Trichospilus diatraeae , em laboratorio. Pupas de H. armigera foram individualizadas e expostas ao parasitismo por 15 femeas de Trichospilus diatraeae ou por 15 femeas de Tetrastichus howardi , durante 24 h. Apos este periodo, as pupas permaneceram em observacao ate a emergencia dos parasitoides. As porcentagens de parasitismo de Tetrastichus howardi e Trichospilus diatraeae foram de 100%. Em relacao a emergencia, a porcentagem foi de 100% para Tetrastichus howardi e de 90% para Trichospilus diatraeae. O ciclo de vida de Tetrastichus howardi em pupas de H. armigera foi de 15,0 ± 0,0 dias, enquanto que Trichospilus diatraeae completou o desenvolvimento em 15,90 ± 0,10 dias. O numero de individuos de Tetrastichus howardi e Trichospilus diatraeae emergidos por pupa foi de 669,30 ± 33,47 e 816,11 ± 89,22, e razao sexual de 0,91 ± 0,01 e 0,94 ± 0,01, respectivamente. Os parasitoides Tetrastichus howardi e Trichospilus diatraeae parasitam com sucesso pupas de H. armigera em condicoes de laboratorio, demonstrando que esse pode ser um bom hospedeiro para criacao de ambos os parasitoides. Contudo, estudos mais detalhados da relacao parasitoide-hospedeiro sao necessarios para avaliar a viabilidade de inclusao desses parasitoides em programas de manejo integrados de H. armigera.