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Thysanoptera species can transmit virus to Solanaceae family vegetables, including tomato plants for industrial processing, causing the disease known as Tomato Spotted Wilt Virus (TSWV). Thrips resistance to insecticides indicate the urgent need of techniques adequate for Integrate Pest Management practices. The objective was to evaluate the control efficiency (CE%) against Frankliniella schultzei (Thysanoptera: Thripidae) of the fungus Beauveria bassiana (Bb), the resistance inducer potassium silicate (KSil) and the chemical insecticide profenophos + cypermethrin (PC) isolated, or in binary mixtures. The treatments were foliar spraying on tomato plants with Bb (T1), KSil (T2) and PC (T3) isolated or in mixtures of Bb+KSil (T4), PC+KSil (T5) and Bb+PC (T6). Thrips were sampled with white plastic trays at 0, 1, 7, 14 and 21 days after application (daa). The CE% of each product (isolated or in mixtures) differed at all time intervals. The Bb+KSil treatment had highest CE% from 24 hours of application, until the end of the experiment, ranging from 95% (1 daa) to 41.5% (21 daa). The CE% decreased in all treatments with a quadratic curve behavior, throughout time. PC insecticide, isolated, showed a decreased CE% through a linear regression. Grouping analyzes indicated the Bb+KSil effect was more dissimilar than the other evaluated treatments. Synergism between Bb and KSil, in mixture, indicate its potential for Integrated Pest Management programs of F. schultzei in tomato plants for industrial processing. RESUMO Espécies de Thysanoptera podem transmitir vírus para vegetais da família Solanaceae, incluindo plantas de tomate para processamento industrial, causando a doença vira-cabeça do tomateiro (TSWV). A resistência dos tripes a inseticidas indica a necessidade urgente de técnicas adequadas às práticas de Manejo Integrado de Pragas. O objetivo foi avaliar a eficiência de controle (CE%) de Frankliniella schultzei (Thysanoptera: Thripidae) com o fungo Beauveria bassiana (Bb), o indutor de resistência silicato de potássio (KSil) e o inseticida químico profenofós + cipermetrina (PC) isolados, ou em misturas binárias. Os tratamentos foram aplicados via foliar nas plantas de tomate com Bb (T1), KSil (T2) e PC (T3) isolados ou em misturas binárias Bb+KSil (T4), PC+KSil (T5) e Bb+PC (T6). Os tripes foram amostrados com bandejas plásticas aos 0, 1, 7, 14 e 21 dias após a aplicação (daa). A CE% de cada produto (isolado ou em misturas) diferiu em todos os intervalos de tempo. O tratamento Bb+KSil teve alta CE% desde as primeiras 24 horas da aplicação até o final do período experimental, variando entre 95% (1 daa) a 41,5% (21 daa). A CE% diminuiu em todos os tratamentos com um comportamento quadrático ao longo do tempo. O inseticida PC, isolado, apresentou uma diminuição para a CE% através de uma regressão linear. Análises de agrupamento indicaram que o efeito do Bb+KSil foi mais heterogêneo do que o dos outros tratamentos avaliados. O sinergismo entre Bb e KSil, em mistura, indica seu potencial em programas de Manejo Integrado de Pragas de F. schultzei em plantas de tomate para processamento industrial.

Background For the first time, a model was applied at the global scale to investigate the effects of climate change on Dalbulus maidis. D. maidis is the main vector of three plant pathogens of maize crops and has been reported as one of the most important maize pests in Latin America. We modelled the effects of climate change on this pest using three Global Climate Models under two Representative Concentration Pathways (RCPs) using MaxEnt software. Results Overall, climate change will lead to a decrease in suitable areas for D. maidis. In South America, climate change will decrease the areas suitable for the pest, especially in Brazil. However, Argentina, Chile, Colombia, Ecuador, Peru and Venezuela will have small areas that are highly suitable for the corn leafhopper. Outside the pest's range, Ethiopia, Kenya, Rwanda, Burundi and South Africa also should be concerned about the risk of corn leafhopper invasions in the future because they are projected to have conditions that are highly suitable for this insect in some areas. Conclusion This study allows the relevant countries to increase their quarantine measures and guide researchers to develop new Zea mays varieties that are resistant or tolerant to D. maidis. In addition, the maize-stunting pathogens for the areas are highlighted in this modelling. © 2019 Society of Chemical Industry.

This study aimed to assess the glyphosate application effects on the Cerotoma arcuata Oliver (Coleoptera: Chrysomelidae) population in glyphosate-resistant soybean crops. Field studies were conducted with glyphosate and the insecticide endosulfan to observe the effects of these pesticides on C. arcuata, on its damages in the crop and on the populations of natural enemies in glyphosate-resistant soybean crops. Moreover, the lethal and behavioral sublethal response of C. arcuata to glyphosate and endosulfan was conducted in the laboratory. The results of the field and laboratory experiments showed that glyphosate caused moderate toxicity and high irritability in C. arcuata and that endosulfan caused high toxicity and irritability. Therefore, the direct effect of glyphosate on C. arcuata was negative and does not explain the population increases of this pest in glyphosate-resistant soybean. However, the glyphosate also decreased the density of predators. Thus, the negative effect of glyphosate on the predators may be related to population increases of C. arcuata in glyphosate-resistant soybean crops, however, more studies are needed to better evidence this relationship. This study suggests that glyphosate can impact other non-target organisms, such as herbivorous insects and natural enemies and that the use of this herbicide will need to be carefully stewarded to prevent potential disturbances in beneficial insect communities in agricultural systems.