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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.

Herbicides and plant growth regulators are often used in sugarcane management. However, the use of non-selective pesticides can cause adverse effects on the efficiency of beneficial insects in integrated pest management. Within this context, this study aimed to evaluate the effect of such products on the immature stages of the parasitoid Trichogramma galloi. Eggs of Diatraea saccharalis containing the parasitoid at the egg-larva stage and at the prepupal and pupal stages were immersed in test solutions of the following pesticides (maximum recommended doses for sugarcane): herbicides clomazone and diuron + hexazinone, and plant growth regulators trinexapac-ethyl and sulfometuron-methyl. The biological properties evaluated were emergence (F1 and F2) and number of eggs parasitized by T. galloi (F1). The products were classified according to percentage of reduction in emergence and parasitism: harmless (99%). The pesticides evaluated were considered to be harmless or slightly harmful to immature T. galloi and, thus, their use should be preferred for preserving this parasitoid species in sugarcane management programs.

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.

Physic nut (Jatropha curcas L.) is an oilseed, semi-evergreen shrub or small tree of the Euphorbiaceae family, whose seeds contain oil that can be processed into a high quality biofuel. However, there have been reports of arthropods feeding from its leaves, including the green leafhopper Empoasca sp. (Hemiptera: Cicadellidae). The large numbers of this insect, observed in certain periods of the year in many regions of Brazil, are causing damage to the oilseed crops. This study aims at evaluating the fluctuation in green leafhopper population in a physic nut crop in Dourados, Mato Grosso do Sul, to assess possible correlations with rainfall, maximum, average and minimum temperatures. This evaluation was conducted between March 2011 and July 2012. The largest Empoasca sp. populations were recorded in May and June, 2011, and between February and May, 2012. No significant correlation was observed between the weather parameters analyzed and the fluctuation in the Hemiptera population, but there was a trend toward higher population density during the warmer and rainier months. El piñón manso (Jatropha curcas L.) es una oleaginosa de la familia Euphorbiaceae que se destaca por la producción de semillas cuyo aceite tiene características deseables para la producción de biocombustibles. Sin embargo, hay informes de algunos artrópodos que usan la planta como fuente de alimento, incluyendo la cigarrita verde Empoasca sp. (Hemiptera: Cicadellidae). La alta incidencia de este insecto se comprueba en varias regiones del Brasil, en ciertas épocas del año, causando lesiones a esta oleaginosa. El objetivo de este estudio fue evaluar la fluctuación de la cigarrita verde en una plantación de piñón manso en Dourados, Mato Grosso do Sul, y la búsqueda de posibles correlaciones con las precipitaciones y las temperaturas máximas, medias y mínimas. Esta evaluación se realizó entre los meses de marzo 2011 hasta julio 2012. Poblaciones mayores de Empoasca sp. Se registraron en mayo y junio de 2011 y entre febrero y mayo de 2012. No hubo correlación entre los aspectos climáticos analizados y entre la fluctuación poblacional de los hemípteros, pero se observó una tendencia a una mayor densidad poblacional en los meses más cálidos y húmedos.

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.