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The stable fly (Stomoxys calcitrans) and horn fly (Haematobia irritans) are mainly parasites of cattle that spend the early phase of their life cycle in decaying vegetation, manure and soil, as members of a wide range of other harmful and beneficial arthropods. Predators of the family Macrochelidae are considered beneficial mites that have been considered promising biological control agents of fly eggs and larvae and of other harmful organisms. The objectives of this study were: a) to compare the predation and oviposition rates of three Macrocheles species, M. embersoni, M. muscaedomesticae and M. robustulus, on six prey species: S. calcitrans, Musca domestica , H. irritans, Bradysia matogrossensis, Rhizoglyphus echinopus and the free living nematode Rhabditella axei; b) to evaluate the life cycle of the best performing predator (M. embersoni) on the most suitable prey species at 30 ± 2°C, 95 ± 5% RH and in the dark. The three macrochelid species consumed all evaluated prey species, but M. embersoni had higher predation and daily oviposition rates on larvae of S. calcitrans (23.8 larvae consumed and laid about 4.0 eggs, respectively) than other species. Total immature development of M. embersoni was completed in at most about 1.3 days on eggs of S. calcitrans and M. domestica and 1.5 days on R. axei. Macrocheles embersoni produced most eggs (0.28-0.34 female/female/day; r m : 0.28-0.34) on those same prey. The results of this study suggest that M. embersoni is a promising biological control agent of S. calcitrans and M. domestica.

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Litchi (Litchi chinensis Sonnerat) is native to Southeast Asia, where most of the world cultivation of this crop is done. Its commercial cultivation in Brazil is recent and concentrated in the state of São Paulo. This crop has been severely damaged in Asia and Brazil by the litchi erineum mite, Aceria litchii (Keifer) (Eriophyidae). The objectives of this study were the adaptation of a method to estimate the density of A. litchii, an evaluation of the population dynamics of this pest and of its associated predators in the state of São Paulo, and an estimation of its injury levels to litchi trees. To estimate the density of A. litchii, an adaptation of a method commonly used to evaluate nematode densities in plant roots was performed. This method was shown to be adequate for the estimation of the number of A. litchii, and it might also be useful for similar evaluations of other erineum forming mites. Field samples to determine the pest population dynamics were collected monthly from August 2011 to July 2012. Sampled leaves were examined under a stereomicroscope for removal of predators and subsequent extraction ofA. litchii by the adapted method. A. litchii reached maximum densities in November 2011 and June 2012, being found at low densities between January and March 2012. The pattern of variation of A. litchii injury levels was similar to that of the density of A. litchii. The main predatory mite co-occurring with A. litchii was the phytoseiid Phytoseius intermedius Evans and McFarlane. However, high injury levels due toA. litchii suggest that the predator was unable to prevent visible damages to the trees, indicating that control activities should be adopted by growers.

The litchi erineum mite, Aceria litchii (Keifer), is the major pest of litchi, Litchi chinensis Sonnerat (Sapindaceae). This study evaluated the effect of 11 pesticides on the survival of A. litchii as well as on the survival and reproduction of Phytoseius intermedius Evans & McFarlane, the predator most found in association with it in Brazil. The containment of A. litchii in small petri dishes whose bottoms were covered with a solidified paste made of a mixture of gypsum and activated charcoal (9:1 in volume), kept humid, was shown to be adequate for this type of study. For the evaluation of the effect of pesticides on A. litchii, mites leaving the erinia from the pieces of litchi leaves (removed from the plants approximately 24 h earlier) were sprayed under a Potter tower and immediately transferred to the 2.5-cm-diameter petri dishes. After 2, 12, 24, and 48 h of the application, the dishes were examined to evaluate the mite survival. The four pesticides causing the highest levels A. litchii mortality, as well as azadirachtin, were tested for the effect on P. intermedius. For this test, experimental units consisted of discs of uninfested litchi leaves also sprayed under a Potter tower before introducing the predators. Survival and oviposition of the predator were evaluated every 24 h for 5 consecutive days; viability of the eggs laid was also evaluated. Highest mortality of A. litchii occurred with the application of fenpyroximate, sulfur, abamectin, and hexythiazox. Azadirachtin was considered moderately harmful to the predator P. intermedius, whereas other pesticides were classified as harmful. Despite the low efficiency of azadirachtin in the control of the pest, its relative selectivity to P. intermedius would encourage the evaluation on field condition, especially for use in organic production systems.

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Macrochelid mites have been reported in several papers about mites of different habitats in Brazil, but this is the first work specifically conducted to determine the macrochelids from that country. The main goal was to determine macrochelid species in microhabitats where the stable fly is usually found in commercial cattle farms. In total, 1359 specimens were collected from cow manure and litter in different regions of São Paulo state. These represented ten species of three genera. One of these, Macrocheles embersoni n. sp. is here described as new to science. Other macrochelid species are expected to be found in the study area, when other types of microhabitats are explored.

S istemas de produção agrícola com bases agroecológicas vêm ganhando visibilidade nos últimos anos, sendo hoje uma forma de agricultura adequada aos princípios da sustentabilidade e preservação ambiental (Finatto & Côr-rea, 2010), além de ser uma atividade econômica interessante devido à maior valoração de seus produtos e ser uma atividade que oferece segurança ao trabalhador rural. O tomateiro em sistema orgânico destaca-se entre as oleráceas devido ao seu alto valor econômico e ao grande desafio que é seu cultivo, visto que atualmente existem poucas informações sobre técnicas de manejo cultural e de controle fitossanitário (Melo et al., 2009).O tomateiro é a espécie olerícola cultivada mais sujeita à ocorrência de problemas fitossanitários (Filgueira, 2003), sendo intensamente atacado por insetos-praga durante todo o seu ciclo, desde a sementeira até a colheita dos frutos. A grande área foliar e o microclima favorável criado pela planta de tomate propiciam um ambiente ideal para o bom desenvolvimento de pragas e doenças (Naika et al., 2006).Atualmente, uma estratégia importante utilizada pela agricultura sustentável é a incorporação e o manejo da diversidade vegetal na paisagem agrícola. A diversidade vegetal é importante para a estabilidade da densidade populacional dos insetos fitófagos, pois GOMES FB; FORTUNATO LJ; PACHECO ALV; AZEVEDO LH; FREITAS N; HOMMA SK. 2012. Incidência de pragas e desempenho produtivo de tomateiro orgânico em monocultivo e policultivo. Horticultura Brasileira 30: 756-761. Incidência de pragas e desempenho produtivo de tomateiro orgânico em monocultivo e policultivo RESUMOO objetivo com este experimento foi comparar o cultivo do tomateiro em monocultivo e policultivo (consórcio com coentro, cravo-de-defunto e o sorgo como cultura circundante) no sistema de produção orgânico, em relação à incidência de pragas, rendimento e qualidade de frutos. Foram avaliados a incidência de tripes, plantas e frutos com sintomas de virose (%), frutos broqueados por Neoleucinodes elegantalis (%), a produtividade total e comercial, o número total e comercial de frutos, o peso médio e o diâmetro dos frutos comercializáveis, o teor de sólidos solúveis totais (SST), o teor de acidez total titulável (ATT) e a relação SST/ATT. No policultivo ocorreu menor número de tripes e, consequentemente, menor percentagem de plantas e frutos com sintomas da virose. A incidência de broqueamento de frutos por N. elegantalis também foi menor em policultivo. A produtividade total e o número total de frutos no monocultivo foram superiores à do policultivo. Porém, a produtividade comercial foi igual nos dois sistemas de cultivo. O diâmetro dos frutos não diferiu entre os tratamentos, mas o peso médio dos frutos oriundos do monocultivo foi maior. Os frutos do policultivo apresentaram maiores teores de SST e ATT e a relação SST/ATT não diferiu entre os tratamentos. Assim, reforça-se a importância da diversidade vegetal no manejo de pragas, sendo necessários novos estudos que permitam definir melhor arranjo espacial das planta...