Made available in DSpace on 2017-07-10T14:38:29Z (GMT). No. of bitstreams: 1 cristiane Oficial CD.pdf: 1800136 bytes, checksum: 90ce26316dd58731f112c41b5247fc7d (MD5) Previous issue date: 2016-03-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Brazil is one of the largest producers of eggs, and this production is constantly growing, based on investment independent producers and the creation of cooperatives. Brazilian poultry facilities are mainly in wood with metal cages. There are few fully automated poultry, mainly by the high initial investment they require. The wooden structures, usually older, favor the appearance of some arthropod pests, as the poultry red mite Dermanyssus gallinae (De Geer, 1778) (Acari: Dermanyssidae). This mite is hematophagous and features gregarious and nocturnal behavior, spending the day hiding in cracks and crevices of the poultry houses, timber slots, dirt and debris accumulation of food and cobwebs. Among the damage caused by this mite infestation highlights the stress of birds, dermatitis and anemia, which can cause a decrease in production. Moreover, D. gallinae can also be transmitter the bacteria genus Salmonella, viruses of Newcastle disease and avian pox. Control strategies are mainly based on the use of chemical acaricides, which present risks to animals, poultry farmers and eggs consumers by residues in the eggs. Also, can select populations of resistant mites. Currently, the integrated management with use of less impactful strategies has been researched aiming their use at the field level. Among these strategies include the use of extracts and essential oils, inert powders (diatomaceous earth, silicas, talc), predators and entomopathogenic fungi. The entomopathogenic fungus has emerged as one of the most efficient techniques to control D. gallinae in laboratory conditions, but with a few field studies. The combination of these control strategies are also being studied aiming to find a method that is efficient and at the same time represents no risk to human and animal health. / O Brasil está entre os maiores produtores mundiais de ovos, sendo esta produção em constante crescimento, impulsionada principalmente por investimento de produtores independentes e da criação de cooperativas. As instalações aviárias brasileiras são principalmente em madeira com gaiolas metálicas. Há poucos aviários completamente automatizados, principalmente pelo alto investimento inicial que estes exigem. As estruturas em madeira, geralmente mais antigas, favorecem o aparecimento de alguns artrópodes-pragas, dentre os quais destaca-se o ácaro vermelho das galinhas Dermanyssus gallinae (De Geer, 1778) (Acari: Dermanyssidae). Este ácaro é hematófago e apresenta comportamento gregário e hábitos noturnos, passando o dia escondido em frestas e fendas dos aviários, ranhuras da madeira, restos de sujeira e acúmulo de comida e teias de aranha. Dentre os prejuízos causados pelas infestações deste ácaro, destacam-se o estresse das aves, a dermatite e a anemia, a qual pode ocasionar diminuição da produção. Além disso, D. gallinae também pode ser transmissor de bactérias do gênero Salmonella, vírus causadores da doença de Newcastle e da varíola aviária. As estratégias de controle são baseadas principalmente no uso de acaricidas químicos, os quais representam riscos aos animais, aos avicultores, aos consumidores pelos resíduos que podem deixar nos ovos, além de selecionar populações de ácaros resistentes. Atualmente, o manejo integrado com utilização de estratégias menos impactantes está sendo pesquisado, visando sua utilização no controle da praga. Dentre estas estratégias, destacam-se os extratos e óleos essenciais vegetais, pós inertes (terra de diatomáceas, sílicas, talcos), predadores e fungos entomopatogênicos. Os fungos entomopatogênicos têm se apresentado como uma das técnicas mais eficientes para controle de D. gallinae em condições de laboratório, porém com poucos estudos de campo. A combinação destas estratégias de controle também estão sendo pesquisadas visando encontrar um método que seja eficiente e ao mesmo tempo não represente riscos a saúde animal e humana.

A Amazônia é tida como a região de maior biodiversidade do Planeta. No entanto, pouco se sabe a respeito da diversidade de ácaros plantícolas nesta região. Dentre estes ácaros estão espécies fitófagas, generalistas e predadoras. Este último grupo é de grande interesse, pois pode haver espécies promissoras para uso em programas de controle biológico de pragas. Já os fitófagos são indesejados devido ao dano que algumas espécies podem causar como é o caso do ácaro-branco Polyphagotarsonemus latus (Banks), o principal ácaro praga na região de Manaus, sobretudo em pimentão. Assim, o objetivo deste trabalho foi determinar a diversidade de ácaros associados às frutíferas nativas da região Amazônica e testar formas alternativas e sustentáveis para o controle do ácaro-branco em pimentão nesta região. Foram realizadas coletas no campus da Universidade Federal do Amazonas (UFAM), na fazenda Experimental da UFAM e no município de Anamã, Iranduba e Manacapurú. Os ácaros retirados de cada amostra foram montados, identificados e quantificados. Para o controle do ácaro-branco foram feitos testes com ácaros predadores nativos da região e com extratos aquoso de folha e inflorescência de Piper aduncum L. Foram coletadas 81 espécies de ácaros das famílias Tetranychidae, Tenuipalpidae, Tarsonemidae, Phytoseiidae e Ascidae. Nenhum dos predadores estudados mostrou-se eficiente para o controle do ácaro-branco, apresentando baixa sobrevivência e taxa de oviposição, quando alimentados com esta praga. Extratos aquosos a base de P. aduncum em altas cocentrações mostraram-se promissores para o controle de P. latus, sendo seletivo ao ácaro predador Amblyseius largoensis (Muma). / The Amazon region is considered the most biodiverse on the planet. In however, little is known about the diversity of plants mites in this region. Among these mites are phytophagous species, generalist and predators. This latter group is of great interest because there may be promising species for use in biological control programs of pests. Since the phytophagous are unwanted because of the damage that some species can cause as is the case of broad mite Polyphagotarsonemus latus (Banks), the main mite pest in the Manaus region, especially in pepper. Thus, the objective was to determine the diversity mites associated with fruit native to the Amazon region and test alternative and sustainable ways to control the mite in peppers in this region. Collections were made on the campus of Universidade Federal do Amazonas-UFAM (Federal University of Amazon), in the experimental farm of UFAM and at the municipality of Anamã, Iranduba and Manacapuru. Mites removed from each sample were mounted, identified and quantified. To the broad mite control, were tested native predatory mite and aqueous extracts of leaf and inflorescence of Piper aduncum L. We collected 81 species of mites of the families Tetranychidae, Tenuipalpidae, Tarsonemidae, Phytoseiidae and Ascidae. None of the predators studied was efficient to control the mite, with low survival and oviposition rate when fed with this pest. Aqueous extracts the basis of P. aduncum in high cocentrações proved promising for the control of P. latus, being selective to predatory mite Amblyseius largoensis (Muma).

Plant-based defence mutualisms involve aspects of plant morphology that influence the performance of plant parasites, their natural enemies and trophic interactions. Leaf domatia, small indentations on the underside of leaves, can be structurally complex, and are often inhabited by potentially beneficial mites and other arthropods. Plant morphological traits such as domatia that enhance mutualistic relationships may result in increased plant growth rates, and reproductive success. New Zealand supports ~60 plant species that have domatia, the most speciose genus being Coprosma. The aim of this thesis was to examine factors that affect the production of leaf domatia and their relationship with foliar mite assemblages. The three main objectives of this thesis are: First, to investigate the production of foliar domatia and their susceptibility to limited resources, particularly to carbon availability. Second, to test if domatia are inducible structures during leaf ontogeny in the presence of foliar mites and/or fungi. Finally, to explore the effect of domatia availability on foliar mite assemblages on leaves with and without resident mites. This thesis tested the stated objectives using C. lucida, C. ciliata, C. foetidissima and C. rotundifolia, with a combination of field investigations and controlled manipulative experiments. The cost of domatia production was investigated using two field surveys and two controlled experiments. Under natural conditions the relationship between leaf morphology and domatia were measured in situ and across an altitudinal gradient. The experimental manipulations used carbon and nutrient stress, induced by temperature, light and fertilizer application. The second objective was experimentally tested under field conditions by manipulating foliar mites and fungal densities on C. rotundifolia. The third objective was investigated by manipulating domatia availability on C. lucida shrubs across three different vegetation types. Under field conditions, the number of domatia per leaf was associated with leaf morphology in C. lucida and C. foetidissima, but not C. rotundifolia. Foliar carbon showed a positive, but weak association with domatia production in C. foetidissima and C. ciliata. Altitudinal induced-carbon stress on domatia production was ambiguous. Domatia production in C. foetidissima was positively associated to altitude in field survey (1), and negatively associated in the second survey, with no correlation found between carbon and altitude. Experimental C. rotundifolia shrubs held under elevated night-time temperatures showed a 2.5 fold increase in respiration, a 34% to 91% decrease in daily carbon gain, and 38% decrease in domatia per leaf mass. Domatia production showed no significant differences under nutrient stress. The results showed little evidence to support a role for induction of domatia. Domatia production in new leaves was similar across all experimental treatments. Diverse vegetation types supported 60% higher mite species. Leaves with domatia supported ~22 to 66% higher mite densities, greater colonisation success and more diverse mite assemblages, than those without domatia. In the pastoral vegetation, the absence of predatory mites on experimental shrubs resulted in no differences in fungivorous mite densities regardless of domatia availability. Plant investment in foliar domatia appears associated with the number of available sites on the leaf under field conditions. The role of carbon availability during leaf ontogeny suggests a complex and highly variable association with domatia production. Domatia are constitutive defence structures that influence mite assemblages, mediating both beneficial and antagonistic relationships. This thesis concludes that domatia are in part, carbon-based non-inducible structures that influence mite assemblages, plant-mite and mite-mite interactions, and increase the probability of successful colonisation.

Understanding the transport of particulate and gaseous indoor air pollutants from source to exposure is paramount to improve our understanding of the complexities of the built environments in which we spend the majority of our time. This dissertation offers new insights on particle resuspension from indoor surfaces, infant exposure to organic contaminants released from crib mattresses, and the dynamics of pollutant transport and human exposure while sleeping. Particle resuspension is the physical process by which settled particles detach from a surface and become airborne through application of various aerodynamic and mechanical removal forces. Resuspension is an important indoor source of coarse mode particles (> 1 µm in diameter) and can be a source mechanism for biological matter and organic contaminants that accumulate in house dust. Settled dust deposits on indoor surfaces can vary considerably in their structure and mass loading, yet little is known as to how these parameters affect resuspension. Through wind tunnel experiments, this research demonstrates that the deposit structure (monolayer or multilayer) can have a significant impact on the number of particles that aerodynamically resuspend. Furthermore, this dissertation presents the first full-scale experimental chamber study to show that human body movements in bed can resuspend settled mattress dust particles. An indoor aerosol model was utilized to provide a mechanistic understanding of the impact of movement intensity, surface vibrations, bedroom ventilation rate, and dust loading on the resuspension flux and intake fraction of resuspended particles. Infants spend most of their time sleeping and are likely to be exposed to elevated concentrations of chemicals released from their crib mattresses. Through a combination of chamber experiments and solvent extractions, this research shows that infant crib mattresses can emit a variety of volatile organic compounds (VOCs) and contain numerous chemical additives, including phthalate and alternative plasticizers, flame retardants, and unreacted isocyanates. Additionally, this study discovered that infants are exposed to approximately twice the concentrations of VOCs in their breathing zones as compared to the bulk bedroom air, due to their close proximity to the source.

Clearcut harvesting can create conditions unfavourable to forest regeneration. In response, variable retention harvest methods are being investigated in montane forests on Vancouver Island, Canada. The effect of this overstory removal is unknown for canopy microarthropods, especially oribatid mites. As mites contribute significantly to nutrient cycling and decomposition processes in the canopy, changes in community structure and abundance may have dramatic effects on forest productivity. I studied the effects of two variable retention treatments, patch-cut and shelterwood systems, on arthropod communities associated with Abies amabilis (amabilis fir) branches and lichens. Changes in community structure were evident among the treatments and an old-growth control site. I also investigated the use of lichen abundance as a surrogate for oribatid mite abundance because it is time consuming and laborious to collect, count and identify microarthropods. Lichen abundance was a good predictor of mites in the old-growth and shelterwood, but not in the patch-cuts. Lichen abundance estimates should not replace biotic inventories, but can he used as an indicator when rapid biodiversity assessments are required.

Darbo tema: „Bičių šeimos kaip gamybos priemonės tyrimai“. Duomenys rinkti 2012-2013 metais iš 10 bitynų, kurie yra šiaurės rytų Aukštaitijos regione. Apklausti 5 bitininkai profesionalai ir 5 bitininkai mėgėjai. Raktiniai žodžiai: bitės, Varroa destructor erkės. Apie 64 proc. Lietuvos bitininkų savo bitynuose nekeičia bičių motinėlių, todėl sumažėja bičių produktyvumas. Taip pat, didžiausia bitynų problema yra Varroa destructor erkės, kadangi jos ne tik nualina bičių šeimą, bet yra viena iš esminių priežasčių, dėl bičių mirtingumo po žiemojimo. Darbo tikslas yra įvertinti veiksnius, labiausiai įtakojančius bičių populiacijos mažėjimui ir bičių produktyvumui. Taip pat išanalizuoti bitininkų kompetenciją bitininkystės srityje mėgėjų ir profesionaliuose bitynuose. Darbo uždaviniai: įvertinti bičių šeimų produktyvumą profesionaliuose bitynuose ir mėgėjų bitynuose: • Įvertinti Varroa destructor erkių paplitimą bičių šeimose; • Įvertinti Varroa destructor įtaką bičių šeimų produktyvumui; • Palyginti veislinių ir mišrūnių bičių produktyvumą; • Nustatyti, bičių šeimų, kuriose buvo keistos motinėlės produktyvumą ir atsparumą Varroa destructor erkėms; • Įvertinti medaus kokybinius rodiklius tirtuose bitynuose pagal medaus techninio reglamento reikalavimus; Atlikus analizę paaiškėjo, kad: • Produktyviausios bičių šeimos, kuriose bičių motinėlė keičiama kas du metus, ir nesirgo varoze. • Bičių šeimos sergančios varoze yra mažiau produktyvios. Iš sergančios šeimos profesionaliame... [toliau žr. visą tekstą] / Topic of the paper: “Research of a beehive as a mean of production”. Data collected from 10 apiaries in the region of northeast Upper Lithuania in the year 2012-2013. 5 professional and 5 amateur beekeepers were interviewed. Key words: bees, Varroa destructor mites. It is argued that about 64% of Lithuanian beekeepers apiaries does not change the queen bee, which reduces the productivity of the bees. Also, the biggest problem of the apiaries is Varroa destructor mites, which not only exhausts a beehive, but it is one of the most significant reasons for bee mortality after hibernation. Aim of the paper is to evaluate the most influential factors in declining of bee population and productivity. Also to analyze beekeepers competency in the fields of amateur an professional apiaries. Tasks of the paper: evaluate the productivity of bee colonies in professional and amateur apiaries. • Evaluate the spread of Varroa destructor mites in beehives; • Evaluate the influence of Varroa destructor to the beehive productivity; • Compare the productivity of pedigree and hybrid bees; • Identify beehives that productivity and immunity were affected by Varroa destructor mites; • Evaluate qualitative indicators of honey according to honey technical regulation requirements; The analysis shows that: • The most productive beehives are the ones where the queen bee is substituted every two year and never had varroasis; • Beehives that had varroasis are less productive. 35 kg or 27% less honey is... [to full text]

[Truncated abstract] The last few decades have witnessed an increase in the prevalence, morbidity and economic burden associated with asthma and allergic disease. This rising incidence cannot be completely explained by changes in genetic factors or by improvements in diagnostic procedures. Environmental factors, particularly those associated with a westernised lifestyle, are considered to be involved in this increase. In the late 1980’s Strachan was the first to link environmental factors with allergic disease, this theory became to be known as the ‘hygiene hypothesis’. This hypothesis links the “cleaner” more “healthy ” environment we now live in, with an increased risk of developing allergic disease. This effect is highlighted by studies linking farm and animal exposure (rich in microbial compounds) during early life with a decrease in allergic disease. Since then numerous studies have been undertaken to ascertain the factors present in the microbe rich environment, which elicit this protective effect. Many studies have revolved around endotoxin, however microbial components (mainly from Gram-positive bacteria) which signal through Toll-like receptor 2 (TLR2), have also shown that they can alter the allergic immune response. In mice models TLR2 has been shown to both exacerbate and inhibit allergic disease. The above research highlights the need for further studies into the effect of TLR2 ligands, and to define the mechanisms by which they exert their effects in human allergic disease. These mechanisms will be relevant to understanding the pathogenesis of allergy, but also might provide novel ways to treat allergy. The aims of the study outlined in this thesis were to determine whether in vitro exposure to TLR2 ligands could modify the established immune response to house dust mite allergen (HDM), and to examine the mechanisms by which this occurs. ... The addition of glucocorticoids to LTA enhanced the ability of this TLR2 ligand to inhibit IL-5 and IL-13 production by HDM-activated blood mononuclear cells. In conclusion, this study shows that TLR2 ligands have the ability to inhibit the Th2 response to mite allergen in previously sensitized individuals by an as yet unknown mechanism. However the findings described herein do provide an impetus for future studies designed to uncover novel mechanisms by which allergic responses can be ameliorated, and may open new treatment modalities.

Clearcut harvesting can create conditions unfavourable to forest regeneration. In response, variable retention harvest methods are being investigated in montane forests on Vancouver Island, Canada. The effect of this overstory removal is unknown for canopy microarthropods, especially oribatid mites. As mites contribute significantly to nutrient cycling and decomposition processes in the canopy, changes in community structure and abundance may have dramatic effects on forest productivity. I studied the effects of two variable retention treatments, patch-cut and shelterwood systems, on arthropod communities associated with Abies amabilis (amabilis fir) branches and lichens. Changes in community structure were evident among the treatments and an old-growth control site. I also investigated the use of lichen abundance as a surrogate for oribatid mite abundance because it is time consuming and laborious to collect, count and identify microarthropods. Lichen abundance was a good predictor of mites in the old-growth and shelterwood, but not in the patch-cuts. Lichen abundance estimates should not replace biotic inventories, but can he used as an indicator when rapid biodiversity assessments are required.

The mate-tea tree it is a forest species that occurs naturally in the tempering regions and subtropical of America of the South. In Brazil it occurs mainly in the states of the Rio Grande do Sul, Paraná and Santa Catarina. Its leaves and branches are used, mainly, as raw material in the preparation of teas. During many years, the exploration of mate-tea if restricted the natives plants, but recently it passed also to be cultivated in monoculture, system that favors the development of pragues. The tan-mite, Dichopelmus notus (Keifer, 1959) (Acari, Eriophydae), specific plague of this culture, that before met in low population levels, currently due to the high infestations, cause the premature leaf fall and death of the tips, with elevated damages to the producers. This mite comes being considered as one of the main pragues of the culture of mate-tea in the Argentine and Brazil. In result of the importance of mate-tea and of the increase of the infestation of this mite, it is necessary to search alternatives and technologies that maximize the profitability of the culture. This work aimed to select a sampling methodology to monitor the levels of infestation of the tan-mite in matetea orchards, destined to explain its habits. The study were carried out in orchard of ten years, in the arrangement of 2,5 X 4,0 m with height of 1,5 m, located in the Chapecó county, Santa Catarina state, Brazil. In three areas of approximately 2,500 m2, distant between itself about 100 m, had been selected 30 plants randomly. Fortnightly, in the period of 27/01/2004 the 10/01/2005, were evaluated infestation of D. notus in 18 mature leaves of ten plants in each area, being six in the upper one-third, six in the medium one-third and six in lower one-third, three in each localization of the crown, external and internal. The evaluations were executed directly in the orchard, using lenses with increase of ten times and 1 cm2 of fixed field. The results had evidenced that: the infestation of the mite occurs of aggregate form; the estimate of the average number of mites for cm2 of leaf, with level of 15% precision, can be carried through in three leaves of 30 plants in sections of hectare, from february to april; the mites concentrate themselves in the external part of the plant in the upper one-third part of canopy as well as at part medium one-third; positive correlation was observed among the population of D. notus and minimum and maximum temperatures, however negative correlations was observed among tan-mite e population and rain precipitation, relative humidity and speed of the wind; the Model of Normal Approach with Correction of Continuity must preferential be used in the elaboration of binomial sequential sampling plans for D. notus. / A erva-mate é uma espécie florestal que ocorre naturalmente nas regiões temperadas e subtropicais da América do Sul. No Brasil ocorre principalmente nos estados do Rio Grande do Sul, Paraná e Santa Catarina. Suas folhas e outras partes do ramo são utilizadas, principalmente, como matéria-prima no preparo de chás. Durante muitos anos, a exploração da erva-mate se restringiu a ervais nativos, mas recentemente passou a ser cultivada também em monocultura, sistema que favorece o desenvolvimento de pragas. O ácaro-do-bronzeado, Dichopelmus notus (Keifer, 1959) (Acari, Eriophydae), praga específica dessa cultura, que antes encontrava-se em baixos níveis populacionais, atualmente devido às altas infestações, provoca a queda prematura de folhas e morte dos ponteiros, com elevados prejuízos aos produtores. Esse ácaro vem sendo considerado como uma das principais pragas da cultura da erva-mate tanto na Argentina como no Brasil. Em decorrência da importância da erva-mate e do aumento da infestação desse acarino, é necessário buscar alternativas e tecnologias que maximizem a rentabilidade da cultura. Este trabalho teve como objetivo selecionar uma metodologia de amostragem para monitorar os níveis de infestação do ácaro-do-bronzeado em lavouras de erva-mate, destinada a esclarecer aspectos de sua bioecologia. O estudo foi conduzido em erval de dez anos, no espaçamento de 2,5 X 4,0 m com altura de 1,5 m, localizado no município de Chapecó, SC. Em três áreas de aproximadamente 2.500 m2 , distantes entre si cerca de 100 m, foram selecionadas 30 plantas ao acaso. Quinzenalmente, no período de 27/01/2004 a 10/01/2005, avaliou-se a infestação de D. notus em 18 folhas maduras de dez plantas em cada área, sendo seis no terço superior, seis no terço médio e seis no terço inferior, em cada terço, três na parte externa da copa e três na interna. As avaliações foram executadas diretamente nos ervais, utilizando lentes com aumento de dez vezes e 1 cm2 de campo fixo. Os resultados evidenciaram que: a infestação do ácaro ocorre de forma agregada; a estimativa do número médio de ácaros por cm2 de folha, com nível de precisão de 15%, pode ser realizada em três folhas de 30 plantas em talhões de um hectare, nos meses de fevereiro a abril; os ácaros concentram-se na parte externa da copa da planta nos terços superior e médio; há correlação positiva entre a população de D. notus e temperaturas mínimas e máximas e correlações negativas com a precipitação pluviométrica, umidade relativa e velocidade do vento; o Modelo de Aproximação Normal com Correção de Continuidade deve ser preferencialmente utilizado na elaboração de planos de amostragem seqüencial binomial para D. notus.

Made available in DSpace on 2015-03-26T13:30:34Z (GMT). No. of bitstreams: 1 texto completo.pdf: 551630 bytes, checksum: f10529c8ae7ae2927d1c12cde8edce77 (MD5) Previous issue date: 2011-02-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Jatropha curcas (physic nut) is a promising plant for extraction of biodiesel. In the state of Tocantins the physic nut has been cultivated in rural settlements with maize, cassava, pumpkin, and the presence of weeds. This crop is attached by a large number of pests. The key pests in this crop system are Tetranychus bastosi and Polyphagotarsonemus latus. Predatory mites Iphsiseiodes zuluagai and Euseius concordis are associated with these pests. To increase the efficiency of predators in pest control is important to assess the effect of mixed diets. Mixed diets may consist of different prey species or even the addition of alternative food such as pollen, in the case of predatory mites. In the first chapter the effect of diets composed of T. bastosi and P. latus in the performance of predators I. zuluagai and E. concordis was evaluated. A mixed diet did not result in increases in predation rates, but higher average number of eggs deposited was found in this treatment for both predators. Suggesting that the mixed diet is more nutritious for predators, requiring a smaller number of prey to achieve higher oviposition. When was tested separately the effect of the stages mixture of T. bastosi, it was observed that E. concordis has low rates of predation and oviposition. Indicating that the good performance achieved in the previous experiment is due to the mixing of two species of prey and not the presence of different stages of the same species. In the second chapter was evaluated the performance of predators on pollen from plants intercropped with physic nut crops. There was no effect on oviposition rates of the I. zuluagai and E. concordis when they fed different species of pollen. The highest survival rate was recorded in treatment with corn pollen to I. zuluagai. And the highest survival rate was found when in E. concordis fed on corn and Peltaea sp. pollen. / O pinhão-manso é uma espécie rústica promissora na produção de sementes para extração de biodiesel. No estado do Tocantins, vem sendo cultivado em assentamentos rurais juntamente com milho, mandioca, abóbora, além da presença de plantas espontâneas. Esse cultivo abriga um grande número de pragas, sendo consideradas as principais os ácaros fitófagos Tetranychus bastosi e Polyphagotarsonemus latus. Associados a essas pragas, estão os ácaros predadores Euseius concordis e Iphiseiodes zuluagai (Phytoseiidae). Para aumentar a eficiência dos predadores no controle das pragas é importante avaliar o efeito das dietas mistas. Dietas mistas podem ser compostas por espécies de presas ou até mesmo pela adição de alimento alternativo como pólen, no caso de ácaros predadores da família citada. No primeiro capítulo dessa dissertação foi avaliado o efeito das dietas compostas por T. bastosi e P. latus no desempenho dos predadores I. zuluagai e E. concordis. A predação em dieta mista contendo as duas espécies de presas não resultou em incrementos nas taxas de predação, porém maior média de ovos depositados foi encontrada nesse tratamento para ambos predadores. Sugerindo que a dieta mista é mais nutritiva para os predadores, sendo necessário um menor número de presas para alcançar maiores taxas de oviposição. Quando testado separadamente o efeito da mistura dos estádios de T. bastosi., observou-se que E. concordis apresenta baixa taxas de predação e oviposição. Indicando que o bom desempenho obtido no experimento anterior deve-se à mistura das duas espécies de presa e não da presença de diferentes estádios de uma mesma espécie. No segundo capítulo foram selecionadas plantas provedoras de alimento alternativo para os ácaros predadores. Foi avaliado o desempenho dos predadores em pólen provenientes das plantas consorciadas com pinhão-manso. Não foi verificado efeito das diferentes espécies de pólen na taxa de oviposição do predador I. zuluagai e E. concordis. A maior sobrevivências foram registradas no tratamento com pólen de milho para I. zuluagai. E para E. concordis as maiores sobrevivência foram encontradas em pólen de miho e Peltaea sp. Desse modo, o cultivo de milho e presença de plantas espontâneas como Peltaea sp. podem ser importantes para a manutenção dos predadores em campo na ausência de presas.