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BackgroundThe poultry red mite Dermanyssus gallinae negatively impacts bird welfare and health, and interferes with egg production and quality, while emerging acaricide resistance limits control options. Fluralaner, a novel miticide for administration in drinking water, is approved for control of D. gallinae infestations. Mite sensitivity testing is relevant to gauge field isolate susceptibility to available treatments.MethodsThirteen D. gallinae isolates collected during 2014 through 2016 from farms in Germany, France, Spain and Brazil, and a 2001 laboratory-maintained isolate were used for acaricide contact sensitivity testing. Tested compounds were cypermethrin, deltamethrin, phoxim, propoxur, and the recently available acaricides, spinosad and fluralaner. In each study, at least one isolate was exposed to increasing concentrations of at least one acaricide. In one study, additional testing determined the sensitivity of the 2001 isolate to fluralaner using a mite-feeding test, and of fluralaner, phoxim and spinosad using an immersion test. At least two replicates were used for each dilution. Vehicle and untreated controls were also included.ResultsBased on 90% mortality (LC90) values, the laboratory isolate was susceptible to fluralaner (15.6–62.5 parts per million, ppm), phoxim (< 500 ppm), propoxur (< 125 ppm), and deltamethrin (500–1000 ppm). All field isolates remained sensitive to fluralaner concentrations ≤ 125 ppm. Spinosad LC90 values for laboratory and field isolates ranged between 2000–4000 ppm. For phoxim, relative to the laboratory isolate, there was reduced sensitivity of two German isolates (LC90 up to 4000 ppm) and two French isolates (> 4000 ppm). An isolate from Spain demonstrated reduced sensitivity to phoxim, propoxur and deltamethrin; an isolate from Brazil showed reduced sensitivity to propoxur and cypermethrin. Mite LC90 when exposed to fluralaner by blood feeding was < 0.1 ppm.ConclusionsContact sensitivity testing indicated apparent resistance to at least one of phoxim, deltamethrin, cypermethrin and propoxur in 13 field isolates from Europe and Brazil. All isolates were highly susceptible to fluralaner. Fluralaner was approximately 1000 times more active by feeding than by contact. Fluralaner’s distinct mode of action and efficacy against isolates largely refractory to those acaricides, makes it a promising option for the control of D. gallinae infestations of poultry.

O objetivo deste trabalho foi realizar uma análise comparativa entre um livro didático de Biologia utilizado na terceira série do Ensino Médio, da rede estadual de ensino do município de Cascavel, PR, e apostilas utilizadas por duas escolas da rede privada. Após o levantamento e escolha, os materiais didáticos foram submetidos a uma análise geral em relação à capa, encadernação, espaçamento entre linhas, tamanho da letra, ilustrações, quadros e tabelas, e, também, a uma análise específica do conteúdo Filo Mollusca, considerando-se conceitos; sugestões de leituras complementares; erros ortográficos e conceituais; erros de impressão e revisão; ilustrações. Verificou-se que todos os materiais didáticos analisados apresentam falhas. No entanto, em umas das apostilas, foram encontradas mais falhas, pois além do seu conteúdo ser extremamente sucinto e não apresentar um planejamento em relação às atividades propostas, continha imagens incorretas e sem legendas auto-explicativas.

Resumo -O objetivo deste trabalho foi avaliar a interferência dos métodos de bioensaios nos resultados de seleção de fungos entomopatogênicos, com a utilização de quatro isolados de Beauveria bassiana e adultos de Alphitobius diaperinus. Quanto à forma de inoculação, foram testados os seguintes métodos: imersão do inseto em suspensão de conídios; pulverização da suspensão sobre insetos; e tratamento de superfície com a suspensão em oito concentrações. Para avaliar a interferência do tempo de imersão sobre a mortalidade, os insetos foram colocados em suspensão de conídios por 1, 10, 20, 30, 40, 50 e 60 segundos. Conídios produzidos em arroz, insetos e meio sintético foram utilizados para avaliar a influência do substrato na virulência dos isolados. Os isolados UNIOESTE 4 e CG 152 foram os mais virulentos pelos métodos imersão e pulverização, respectivamente; em tratamento de superfície, a mortalidade foi baixa para todos os isolados. Observou-se que a mortalidade dos insetos é proporcional ao tempo em que ficam imersos, com tendência a se estabilizar após 40 segundos. Os isolados CG 71 e CG 152, produzidos sobre insetos, foram menos virulentos. Os métodos utilizados podem influenciar os resultados de bioensaios de seleção de fungos para o controle de insetos.Termos para indexação: Beauveria bassiana, Alphitobius diaperinus, controle biológico, cascudinho, aviário, inoculação. Interference of bioassay methods on the results of entomopathogenic fungi selection for insect controlAbstract -The objective of this work was to evaluate the interference of bioassay methods on the entomopathogenic fungi selection, using four Beauveria bassiana isolates and Alphitobius diaperinus adults. Regarding the inoculation form on insect mortality, the following methods were tested: insects immersion in a conidia suspension; spraying of a suspension over the insects; and surface treatment with eight concentrations. In order to evaluate the interference of immersion time on mortality, insects were immersed in a fungal suspension for 1, 10, 20, 30, 40, 50, and 60 seconds. Conidia produced on rice, insects, and synthetic medium were used to evaluate the influence of substrate on the virulence of the isolates. UNIOESTE 4 isolate and CG 152 were the most virulents for the methods immersion and spray, respectively; however, mortality was low in all isolates for the surface treatment. Mortality was proportional to the time during which insects stayed immersed, with a tendency to become stable after 40 seconds. Conidia from isolates CG 71 and CG 152 produced on insects were less virulent. The methods may influence bioassay results in the fungi selection for insects control.

ResumoOs pulgões são um dos principais problemas fitossanitários da cultura do trigo no sul do Brasil, sendo alvo de um programa de controle biológico por parasitóides implantado no Brasil a partir da década de 1970. A despeito do sucesso inicial rapidamente obtido não há na região oeste do Paraná nenhum estudo recente avaliando a situação atual do controle biológico dos pulgões, sendo este o objetivo do presente trabalho. Foram realizados levantamentos semanais em uma lavoura comercial de trigo em Medianera, PR, sendo os pulgões identificados e quando parasitados, analisados até a emergência do parasitóide. A população de pulgões não alcançou a média de um inseto/afilho, com a predominância de Rhopalosiphum padi (53%), seguido de Sitobion avenae e R. maidis (19,5%) e Metapophium dirhodum (8%), surgindo principalmente a partir da fase de alongamento do trigo. Os parasitóides foram observados a partir da época de floração do trigo (cerca de três meses após o plantio), sendo identificadas apenas duas espécies de braconídeos Lysiphlebus testaceipes (97,3%) e Diaretiella rapae (2,7%), cujo crescimento populacional acompanhou a população de pulgões, seguindo a mesma tendência após a redução do número de pulgões no campo. Palavras-chave: Manejo integrado de pragas, dinâmica populacional, microhimenópteros AbstractAphids constitute one of the main phytosanitary problems in wheat crops in southern Brazil, and are the target of a biological control program with parasitoids implemented in Brazil since the 1970's. In spite of the initial success quickly achieved, no recent study exists for the west region of the State of Paraná that evaluates the current status of aphid biological control; therefore, this was the object of the present work. Weekly surveys were conducted in a commercial wheat crop in Medianeira, PR. The aphids were identified and, when parasitization was verified, they were analyzed until emergence of the parasitoid. The population of aphids did not reach the mean value of 1 insect/tiller, with predominance of Rhopalosiphum padi (53%), followed by Sitobium avenae and R. maidis (19.5%) and Metopolophium dirhodum (8%), which were verified mostly from the wheat elongation stage. The parasitoids were observed starting at the wheat flowering season (about 3 months after planting), and only two species of braconids, Lysiphlebus testaceipes (97.3%) and Diaeretiella rapae (2.7%), were identified, whose population growth followed the aphids population of, keeping the same trend after the number of aphids in the field was reduced.

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The objective of this study was to evaluate the pathogenicity and virulence of isolates of Beauveria bassiana (Unioeste 47 and Unioeste 57), Metarhizium anisopliae (Unioeste 43 and Esalq 09) and Isaria

Entomopathogenic Fungi Selection to Control Oligonychus yothersi (McGregor) (Acari: Tetranychidae) in Paraguay Tea Crops (Ilex paraguariensis St. Hill.) ABSTRACT-The virulence of strains of the entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae and Paecilomyces fumosoroseus was evaluated on Oligonychus yothersi (McGregor) in laboratory. The bioassays for strain selection and determination of LD 50 and LT 50 were elaborated with leaf disks of Paraguay tea infested with 10 adult females of the mite. Groups of five disks were sprayed with 1 ml of the suspension standardized in 1.0x10 7 conidia per ml (50 mites per treatment) of each strain. After that, the disks were maintained floating in distilled water in plastic boxes (3 cm diameter and 1.5 cm height), in environmental chamber (temperature: 25 ± 1ºC; RH: 71 ± 10% and 12h photophase). Five days after the inoculation the total mortality was evaluated, and the dead mites were transferred to humid chamber. Six days after death, the sporulation in the cadavers was examined under an optical microscope. B. bassiana presented great potential as a microbial control agent, and can be incorporated in integrated pest management of the Paraguay tea red mite, O. yothersi. The B. bassiana strains UEL02, UEL08, UEL10, UEL50, CG082, CG166, CG375, CG424 and CG481, were the most virulent, with corrected and confirmed mortality higher than 70% and estimated value of CL 50 varying between 1.9x10 6 and 6.0x10 7 conidia per ml and TL 50 varying between 3.3 and 4.3 days.