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Abroca-da-cana, Diatraea saccharalis, é considerada a principal praga da cana-de-açúcar, causando prejuízos de maneira direta e indireta. Entre os danos diretos, devido à abertura de galerias no interior do colmo da planta pela lagarta, podemos citar a redução da translocação de seiva e a quebra e perda de peso de colmos.

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.

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The species Helicoverpa armigera is one of the most important polyphagous and widely distributed pests in the world. Its occurrence was recently reported on soybean and cotton, in the states of Goias, Mato Grosso and Bahia, Brazil. This study aimed to evaluate the occurrence and density of Helicoverpa armigera in Mato Grosso do Sul State, an important pest for agriculture and identified in Brazil in 2013. 81 Delta trap baited with H. armigera sex pheromone Biocontrole® were installed in 26 counties in the State of Mato Grosso do Sul. Results showed that H. armigera was observed in all counties installed with Delta traps. Furthermore, over 80% of collected moths belong to the H. armigera species, and the cotton regions apparently show a highest occurrence of H. armigera in the pheromone traps. Key words: Monitoring, sex pheromone, sampling.

Helicoverpa armigera (Hubner, 1805) (Lepidoptera: Noctuidae) is an insect pest that attacks several cultures and has been a cause of concern in Brazil. The objective of this study was to evaluate parasitism in pupae and caterpillars of H. armigera by Tetrastichus howardi (Olliff, 1893) (Hymenoptera: Eulophidae), in laboratory, as well as checking if T. howardi parasitoid has the ability to locate and infect H. armigera. In the laboratory, pupae of H. armigera and Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) were exposed to 15 T. howardi females for 24 hours. Third, fourth and fifth instars of H. armigera were exposed to three T. howardi females for 24 hours. In the field experiment, cages were installed. Ten caterpillars of the fifth instar of H. armigera were released in each cage and waited for the necessary period for them to soak in the soil. After this period, 150 T. howardi females were released in each of four cages and in one cage there was no release of parasitoids. In the laboratory, the percentage of parasitized and emergent pupae was 100% in both hosts. The life cycle of T. howardi in H. armigera pupae was 15 days, and for D. saccharalis it was 16 days. The progeny was significantly larger for the host H. armigera (689.00) compared to D. saccharalis (358.27). The sex ratio was 0.91 and 0.87 for H. armigera and D. saccharalis, respectively. The longevity of males (25.60 days) and females (26.95 days) in the treatment with H. armigera differed from the treatment with D. saccharalis, which was 21.70 days for males and 22.95 days for females. For the experiment with H. armigera caterpillars, it was found that only two caterpillars from the fifth instar were parasitized with emergence of parasitoids in the pupal phase, with a progeny of 81 individuals; egg-adult cycle was 19.5 days; sex ratio of 0.88; male longevity was 19.6 days and for females 20.3 days. Despite the high rate of parasitism of T. howardi in H. armigera pupae in the laboratory, the same did not occur for caterpillars. In the field evaluation, of the total of 50 caterpillars released in the cages, 34 pupae were collected. Of these, 31 pupae had emergence of the H. armigera moth. No parasitism by T. howardi was found in H. armigera pupae. Further studies should be conducted to evaluate T. howardi parasitism in H. armigera pupae under field conditions.

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Managing Helicoverpa armigera is still a major challenge for Brazilian farmers, due to limited information available about chemicals and biological control of this pest in Brazil. This study focused on evaluating the biological aspects of Podisus nigrispinus fed with H. armigera, under laboratory conditions, as well as verifying the capacity of the P. nigrispinus in preying on caterpillars of H. armigera in the field, in soybean crops. The experiments were conducted in laboratory under controlled temperature conditions of 25±2 ºC, relative humidity (RH) 60±10% and 14-hour photophase, as well as in the field, at the experimental station of Fundação MS in Maracaju, MS. In the laboratory, second instar nymphs of P. nigrispinus were placed in plastic jars and fed with H. armigera larvae or Tenebrio molitor larvae throughout the nymphal phase. When they reach adulthood, 15 couples were formed, remaining with the same prey of the previous phase. For the field trial, soybean plants were caged, and inside these cages were released eight quarter-instar H. armigera caterpillars. Subsequently, in each cage were released an adult female or a fifth instar nymph, and after 24 hours, the number of prey caterpillars were assessed. Predator nymphal duration was shorter in treatment with H. armigera than with T. molitor. Nymphal viability was similar between treatments. Adult females and males fed with H. armigera presented greater body mass than those fed with T. molitor. The number of postures per female and the number of eggs per female were similar between treatments. The incubation period of eggs was longer for treatment with H. armigera, differing statistically from treatment with T. molitor. Eggs from treatment with H. armigera showed similar viability to treatment with T. molitor, not differing statistically. Females and males under treatment with H. armigera showed longer longevity compared to treatment with T. molitor. Adult females preyed on average 2.26 caterpillars within 24 hours and fifth instar nymphs preyed on 1.73 caterpillars/day. P. nigrispinus showed better development when fed with H. armigera, demonstrating that it can be used as an alternative host for breeding this predator. The predator showed satisfactory performance for predation rate/day. Release of fifth instar nymphs and adult females of P. nigrispinus may reduce the pest population in relation to the absence of the predator under field conditions, an important alternative to be used in H. armigera integrated management programs.

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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.

Vatiga illudens is a pest of economic importance for the cultivation of cassava. Knowing the time of incidence of this insect in combination with environmental factors enables control strategies. The objective of this study was to determine the population dynamics of V. illudens in cassava cultivars and the correlation of these insects for climatic factors in Dourados, Mato Grosso do Sul. Four cultivars of cassava were evaluated: Kiriris, N-25, IAC 90 and Fécula Branca. Population assessment of the lace bug was conducted over 18 months observing 2 crop cycles. Fortnightly, they were randomly sampled four central plants of each plot and five leaves from the middle third of each plant, quantifying the number of nymphs and adults per leaf. Twenty months after planting cassava, two central rows of each plot were harvested and measured productivity in kg ha-1. The experimental design was randomized blocks with four treatments and two replications. The peak population of nymphs and adults for the first crop cycle occurred during the months from March to May. For the second cycle, these population indices happened in the months from January to April. Cultivar Kiriris showed the highest mean number of nymphs and adults per leaf cassava and cultivar IAC 90, the lowest number of insects. There was a negative correlation between the population of adult insects and root yield. The maximum, mean and minimum temperatures affected the population of nymphs V. illudens. These results are fundamental to define management strategies for control of lace bug. RESUMO: Vatiga illudens é uma praga de importância econômica para a cultura da mandioca. Conhecer a época de incidência desse inseto em associação com fatores ambientais possibilita estratégias de controle. O objetivo deste trabalho foi determinar a flutuação populacional de V. illudens em cultivares de mandioca e verificar a correlação desses insetos com os fatores climáticos em Dourados, Mato Grosso do Sul. Foram avaliadas quatro cultivares de mandioca: Kiriris, N-25, IAC 90 e Fécula Branca. A avaliação populacional do percevejo-de-renda foi realizada durante 18 meses, observando 2 ciclos da cultura. Quinzenalmente, foram amostradas aleatoriamente quatro plantas centrais de cada parcela e cinco folhas do terço médio de cada planta, quantificando o número de ninfas e adultos por folha. Vinte meses após o plantio, foram colhidas duas fileiras centrais de mandioca de cada parcela e mensurada a produtividade em kg ha-1. O delineamento experimental foi em blocos casualizados com quatro tratamentos e duas repetições. O pico populacional das ninfas e adultos para o primeiro ciclo da cultura ocorreu nos meses de março a maio. Para o segundo ciclo, esses índices populacionais aconteceram nos meses de janeiro a abril. O cultivar Kiriris apresentou maior número médio de ninfas e de adultos por folha de mandioca e o cultivar IAC 90, o menor número de insetos. Houve correlação negativa entre a população de insetos adultos e a produtividade de raízes. As temperaturas máximas, médias e mínimas afetaram a população de ninfas de V. illudens. Esses resultados são fundamentais para definir estratégias de manejo para controle do percevejo-de-renda.

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.

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Resumo. Durante o manejo da cultura da cana-de-acucar sao utilizados diversos produtos fitossanitarios que podem afetar o desempenho de parasitoides, inimigos naturais da broca-da-cana, Diatraea saccharalis (Fabricius) e consequentemente, o controle biologico da mesma. Assim, objetivou-se avaliar em laboratorio o efeito de herbicidas e reguladores de crescimento de plantas utilizados na cultura da cana-de-acucar, sobre a sobrevivencia, e parasitismo de adultos do parasitoide de ovos Trichogramma galloi Zucchi , assim como sobre a emergencia do parasitoide (F1). Os produtos testados foram: Clomazone, Diuron + Hexazinone (herbicidas); Sulfometuron-methyl e Trinexapac-ethyl (reguladores de crescimento de plantas) nas maiores doses recomendadas a cultura. Ovos de D. saccharalis foram imersos durante 5 segundos em uma das caldas quimicas e, apos secos por 1 hora, oferecidos as femeas de T. galloi, totalizando 20 repeticoes . Avaliou-se a mortalidade e o numero de ovos parasitados pela geracao F0, assim como, a emergencia da geracao F1 de T. galloi , sendo os produtos classificados quanto a toxicidade, conforme percentual de reducao da sobrevivencia, parasitismo e emergencia do parasitoide. Em relacao a sobrevivencia de T. galloi , numero de ovos parasitados pela F0 e a emergencia da F1, Clomazone e Trinexapac-ethyl foram classificados como levemente prejudicais. Diuron + Hexazinone e Sulfometuron-methyl foram inocuos em todos os parâmetros avaliados, com excecao do parasitismo, onde Diuron + Hexazinone foi classificado como levemente prejudicial. Conclui-se que, Clomazone, Diuron + Hexazinone, Trinexapac-ethyl e Sulfometuron-methyl sao inocuos ou levemente prejudiciais a sobrevivencia e parasitismo (F0) de adultos de T. galloi , e a emergencia (F1) desse parasitoide, em laboratorio. Herbicides and Plant Growth Regulators Used in SUGARCANE and their Action on Adult Trichogramma galloi Zucchi (Hymenoptera: Trichogrammatidae) Abstract. During crop sugarcane management, several used pesticides can affect the performance of parasitoids, natural enemies of sugarcane borer, Diatraea saccharallis (Fabricius) and consequently the biological control ofit . Thus, the objective was to evaluate in laboratory the effect of herbicides and plant growth regulators used in the sugarcane crops on survival and parasitism in adults of the eggs parasitoids, Trichogramma galloi Zucchi. The products tested were the herbicides Clomazone and Diuron + Hexazinone, and the plant regulators Sulfometuron-methyl and Trinexapac-ethyl, all in the higher recommended dosages for sugarcane. The eggs of D. saccharalis were immersed during 5 seconds in chemical solutions and, after dry for 1 hour, offered to T . galloi females with 20 repetitions. We evaluated the mortality and number of eggs parasitized by the F0 generation of T. galloi , as well as the emergence of the F1. The products were classified by their toxicity, according to the percentage of reduction in the survival, parasitism and emergence of the parasitoid. In relation to the survival of adult T. galloi , the number of eggs parasitized by F0 as well as the percentage of F1 emergence, clomazone and trinexapac-ethyl were classified as slightly harmful. Diuron+hexazinone and sulfometuron-methyl were harmless in all parameters, except for parasitism, where diuron+hexazinone was classified as slightly harmful. We conclude that clomazone, diuron+hexazinone, trinexapac-ethyl and sulfometuron-methyl, are harmless or slightly harmful the survival and parasitism (F0) of T. galloi adults and emergence (F1) of this parasitoid in the laboratory.

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.

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.