Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-17T18:15:59Z No. of bitstreams: 1 WHALAMYS LOURENÇO DE ARAÚJO - DISSERTAÇÃO PPGHT 2015..pdf: 998803 bytes, checksum: 00aca588e4e5182e7ebe10263ae94f8c (MD5) / Made available in DSpace on 2018-05-17T18:15:59Z (GMT). No. of bitstreams: 1 WHALAMYS LOURENÇO DE ARAÚJO - DISSERTAÇÃO PPGHT 2015..pdf: 998803 bytes, checksum: 00aca588e4e5182e7ebe10263ae94f8c (MD5) Previous issue date: 2015 / Capes / O cultivo do meloeiro (Cucumis melo L.) é de grande importância para a economia brasileira. Seu cultivo tem demonstrado significativa expansão nas duas últimas décadas, especialmente nas regiões Semiáridas do Nordeste. Apesar dos fatores favoráveis à produtividade do meloeiro, vale salientar fatores limitantes, destacando-se os danos ocasionados por pragas que destroem o cultivo e, consequentemente, diminuindo a colheita, obrigando que medidas de controle sejam adotadas. Entres estas, estão aplicações de inseticidas químicos, entre eles os neonicotinoides. Estudos têm demonstrado os danos colaterais destes inseticidas a insetos benéficos como abelhas, que por sua vez são de fundamental importância para a polinização de 90% das angiospermas, principalmente para o melão. Este trabalho teve como objetivo avaliar a toxicidade de neonicotinoides empregados para o controle de pragas na cultura do meloeiro à abelhas A. mellifera Linnaeus. Os bioensaios foram realizados em laboratório, sendo tomadas medidas repetidas no tempo de mortalidade para os produtos comerciais Actara 250 WG (tiametoxam), Evidence 700 WG (imidacloprid), Mospilan (acetamipride) e Orfeu (acetamipride). A exposição das abelhas aos compostos foi realizada por meio de pulverização e ingestão de alimento contaminado com as maiores e menores doses recomendadas pelos fabricantes. Independente do modo de exposição, tiametoxam, imidaclopride e acetamipride (duas formulações) foram tóxicos, diminuindo o tempo de vida útil das abelhas em até 1, 2, 11 e 11 dias, respectivamente, quando comparados com a testemunha, que por sua vez sobreviveram 18 dias, em média. O inseticida tiametoxam foi extremamente tóxico quando pulverizado sobre as abelhas, bem como quando contaminante da dieta ingerida. O imidaclopride também apresentou toxicidade em ambos os experimentos, sendo depois do tiametoxam o mais tóxicos. O inseticida acetamipride apresentou toxicidade, porém não tão alta, quanto às observadas com o tiametoxam e o imidaclopride. / The cultivation of melon (Cucumis melo L.) is of great importance for the Brazilian economy, especially in semiarid regions of the Northeast. Despite the favorable factors to the yield of melon other limiting factors have been highlighted as the damage caused by pests, which undertake to harvest, requiring that control measures are adopted. Among these are applications of chemical insecticides, including the neonicotinoids. Studies have shown the collateral damage of these insecticides to beneficial insects like bees, important pollinators of 90% of angiosperms, mainly to melon. The objective of this study was to evaluate the toxicity of neonicotinoids used for pest control in the melon crop to Linnaeus honeybees. Bioassays were performed in the laboratory, being taken repeated measures in time to mortality commercial products Actara 250 WG (thiamethoxam), Evidence 700 WG (imidacloprid), Mospilan (acetamiprid) and Orpheus (acetamiprid) (two formulations). The exposure of bees to the compounds was performed by spraying and ingestion of food contaminated with higher and lower doses recommended by the manufacturers. Regardless of the exposure mode, all insecticides were toxic, reducing the useful life of bees within 1, 2 and 11 days, respectively, compared with the control (distilled water + pure candy), which survived 18 days, average . The insecticide thiamethoxam in both experiments and doses, was extremely toxic; as well as Imidacloprid, the second most toxic. The Acetamiprid insecticide, in both formulations showed toxicity, but not so high as those observed with other insecticides in the study.

Fruit set in cucurbit crops such as watermelon is entirely dependent upon pollinators, which makes them an important aspect of grower management. This reliance on pollinators means that growers must consider them when making pest management decisions, especially when using pesticides, which can have a negative impact on pollinators. Thus, pest management in watermelon production faces a potential trade-off between pests and pollinators. The ways in which growers manage this trade-off could have a large impact on the communities of both groups and the yield of the crop. <br>

Contexte : L’organisme en développement est très sensible à son environnement. Plusieurs études épidémiologiques ont suggéré la toxicité développementale d’une dizaine de polluants suite à des expositions prénatales. L’objectif général de cette thèse est d’évaluer les conséquences des expositions à des polluants chimiques (consommation de produits de la mer comme vecteur de contamination, solvants organiques et insecticides organophosphorés) pendant la grossesse sur le développement de l’enfant à 2 ans en se focalisant sur le développement neuro-comportemental, le développement respiratoire et immunitaire et le développement staturo-pondéral. Matériel et méthodes : Ce travail s’est appuyé sur la cohorte mère-enfant PELAGIE, mise en place en Bretagne entre 2002 et 2006. Près de 3500 femmes ont été incluses en début de grossesse et environ 1500 couples mère-enfant ont été suivis à 2 ans. Les expositions ont été évaluées en début de grossesse à partir de questionnaires, de matrices emplois-expositions ou de dosage de biomarqueurs d’exposition. Les indicateurs de santé ont été mesurés lors du suivi à 2 ans par questionnaire permettant de recueillir des éléments sur le comportement, les manifestations respiratoires à type de sifflement, les maladies allergiques et la croissance entre la naissance et 2 ans. Résultats : L’exposition professionnelle prénatale aux solvants organiques était associée à des déficits de l’attention/hyperactivité et des niveaux d’agressivité plus importants chez l’enfant à 2 ans. Cette exposition n’était pas associée avec les manifestations respiratoires et allergiques. Nous avons aussi montré que la consommation maternelle de coquillages et crustacés pendant la grossesse était associée à une augmentation du risque d’allergie alimentaire chez l’enfant. Enfin, l’exposition prénatale aux insecticides organophosphorés a été associée à une diminution de la vitesse de croissance en taille à 2 ans. Conclusion : Ce travail renforce l’hypothèse de l’implication de l’exposition prénatale aux polluants chimiques de l’environnement, y compris à faible dose, dans l’origine développementale de la santé et des maladies. / Background: The organism is very sensitive to environment during its developmental period. Number of epidemiological studies has suggested the developmental toxicity of about ten chemical pollutants after prenatal exposure. The general objective of the thesis is to explore the effect of prenatal exposure to certain chemical pollutants (organic solvents, organophosphates pesticides and maternal consumption of fish and shellfish (vectors of pollutants)) on child development at age 2. Methods: This thesis is based on the PELAGIE mother-child cohort that was set up in 2002, in Brittany (FRANCE). In total, 3421 women were included in this cohort at the beginning of pregnancy and 1500 mother- child pairs were followed when the child was 2 years old. Exposures were evaluated at the beginning of pregnancy from questionnaires, job-exposure matrices or measurement of biomarkers of exposure. Health indicators were measured at the 2 years follow-up. At follow-up, questionnaires allowed to obtain information on child behaviour, respiratory manifestations like wheezing, allergies (eczema and food allergy) and growth between birth and the age of two. Results: Prenatal occupational exposure to solvents was associated with higher level of hyperactivity and attention deficit at age 2. This exposure was not associated neither with respiratory nor with allergic manifestations. We also observed that maternal shellfish consumption during pregnancy was associated with a higher risk of food allergy in preschoolers. Finally, higher prenatal exposure to organophosphate pesticides was associated with a decrease height growth velocity at age 2. Conclusion: The present thesis based on the PELAGIE study supported for the hypothesis that prenatal exposure to environmental chemicals may be implicated in the developmental origin of health and diseases.

An drei Standorten wurde die schädlingsregulierende Wirkung einer Raps-Rübsen-Mischsaat (Verhältnis 9:1) gegenüber einer Raps-Reinsaat bewertet. Des Weiteren wurden naturstoffliche und nach § 6a PflSchG selbst hergestellte Pflanzenschutzmittel als auch eine Käfersammelmaschine zur Regulierung der Stängelrüssler (Ceutorhynchus spp.) und des Rapsglanzkäfers (Meligethes aeneus F.) in Labor- und Freilandversuchen angewandt. In der Mischsaat war die Schaderregerabundanz gegenüber der Reinsaat zumeist erhöht. Diese führte zu einem teils signifikant stärkeren Schaderregerbefall der Rapspflanzen in der Mischsaat. Die Mischsaat erbrachte zudem einen teils signifikant geringeren Kornertrag. Natur-Pyrethrum und Spinosad führten im Labor zu deutlich erhöhten Mortalitäten bei den Stängelrüsslern. Im Freiland war kein Effekt erkennbar. Bei der Regulierung der Rapsglanzkäfer wies Spinosad in Feld- und Laborversuchen Wirkungsgrade bis zu 100 % auf. Gespritztes Gesteinsmehl und SiO2 zeigten einen nur geringen Effekt. Für die gleichmäßige Benetzung der Pflanzen mit diesen Präparaten kommt der Formulierung der Pflanzenschutzbrühe und der wiederholten Applikation eine hohe Bedeutung zu. Ökonomisch sind mehrfache Applikationen jedoch abzulehnen. Gestäubtes Gesteinsmehl und die Käfersammelmaschine sind aus Praktikabilitätsgründen nicht geeignet zur Regulierung der Rapsglanzkäfer. Ebenso wenig geeignet sind Quassin, Azadirachtin oder ein Bacillus thuringiensis-Präparat (B.t.t.). Mit Ausnahme einer Spinosad Applikation erzielte keine Pflanzenschutzmaßnahme einen wirtschaftlichen Mehrertrag. Stickstoffmangel und Unkrautkonkurrenz scheinen im ökologischen Rapsanbau häufig stärker auf die Limitierung der Kornerträge zu wirken als ein leichter bis mittlerer Schädlingsbefall. Je besser die Nährstoffversorgung und je geringer die Unkrautkonkurrenz, desto eher kann durch Pflanzenschutz ein wirtschaftlicher Mehrertrag realisiert werden. Die nötigen Pflanzenschutzkonzepte fehlen jedoch weiterhin. / On three sites the pest-regulating effect of a rape-turnip rape mixed cropping system (ratio 9:1) in comparison to rape in pure stand was assessed. Further, natural and self-produced natural insecticide solutions (§ 6a Plant Protection Act) and a beetle collecting machine to regulate the stem weevils (Ceutorhynchus spp.) and the pollen beetles (Meligethes aeneus F.) were applied in laboratory and field experiments. Compared to the fields in pure stand the mixed crop showed a significantly greater abundance of pests. This resulted in a sometimes significantly greater pest infestation of the rape plants in the mixed crop. Furthermore, the mixed crop often had a significantly lower grain yield. The use of natural pyrethrum and Spinosad resulted in significantly higher mortality rates of the stem weevils in laboratory tests. Under field conditions no effect could be detected. In the regulation of the pollen beetles, Spinosad demonstrated under field and laboratory conditions efficiencies of up to 100 %. Sprayed mineral powder or SiO2 had only a slight effect. For a uniform wetting of the plants with these compounds the formulation of the phytosanitary broth and its repeated application are important factors. From an economic perspective, however, repeated applications are inefficient. For reasons of practicality rock-dusted flour and the beetle-collecting machine are not suitable for pollen beetle regulation. Quassin is just as inappropriate as Azadirachtin, or Bacillus thuringiensis (B.t.t.) for the regulation of the pollen beetle. With the exception of one Spinosad application, no protection measure provided an economic surplus. Nitrogen deficiency and weeds seem to more frequently limit grain yield than slight to moderate pest infestation levels. The better the nutrient supply and the lower the weed competition, the more likely by crop protection can be realized an economic surplus. Adequate crop protection strategies, however, have not yet been developed.

<p><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning /> <w:ValidateAgainstSchemas /> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables /> <w:SnapToGridInCell /> <w:WrapTextWithPunct /> <w:UseAsianBreakRules /> <w:DontGrowAutofit /> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <mce:style><! /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0pt 5.4pt 0pt 5.4pt; mso-para-margin:0pt; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} --><!--[endif] --></p><p class="MsoBodyText" style="margin-bottom: 0.0001pt;">U disertaciji je izvr&scaron;ena voltametrijska karakterizacija i određivanje pet&nbsp;neonikotinoidnih insekticida (imidakloprida, tiametoksama, klotianidina, nitenpirama i&nbsp;acetamiprida) na različitim elektrodama na bazi ugljenika, kao &scaron;to su elektroda od&nbsp;ugljenične paste, elektroda od staklastog ugljenika i bizmut-filmom modifikovani&nbsp;staklasti ugljenik. Pored ispitivanja u model-rastvorima, razvijene visokoosetljive&nbsp;diferencijalne pulsne voltametrijskemetode su primenjene za određivanje neonikotinoida&nbsp;u realnim uzorcima. Neonikotinoidi su određivani u uzorcima rečne vode i komercijalnim&nbsp;formulacijama, a praćena je i njihova fotolitička i fotokatalitička razgradnja. Radi&nbsp;potvrđivanja voltametrijskih rezultata, izvedena su komparativna merenja uz primenu&nbsp;tečne hromatografije sa detektorom od niza dioda i infracrvenespektrometrije. Detekcija&nbsp;pojedinih degradacionih proizvoda nastalih u toku ispitivanih fotodegradacionih procesa&nbsp;je praćena tečnohromatografskom metodom sa tandemskom masenospektrometrijskom&nbsp;detekcijom. Proučavana je povr&scaron;inska struktura CR 5 grafitnog praha, elektrode od&nbsp;ugljenične paste na bazi trikrezil-fosfata i elektrode od staklastog ugljenika pomoću&nbsp;skenirajuće elektronske mikroskopije.</p> / <p>This thesis is concerned with the voltammetric characterization and&nbsp;determination of five neonicotinoid insecticides (imidacloprid, thiamethoxam,&nbsp;clothianidin, nitenpyram and acetamiprid) at different carbon-based electrodes such as&nbsp;carbon paste, glassy carbon and bismuth-film modified glassycarbon. In addition to the&nbsp;investigations in model solutions, the developed highly sensitive differential pulse&nbsp;voltammetric methods were applied for the determination of neonicotinoids in real&nbsp;samples. Neonicotinoids were determined in river water samples, commercial&nbsp;formulations, and their photolytic and photocatalytic degradation was also monitored. To&nbsp;confirm the voltammetric results, comparative measurements were performed by liquid&nbsp;chromatography with diode-array detector and infrared spectrometry. Detection of some&nbsp;degradation products formed during the photodegradation processes was monitored using&nbsp;liquid chromatography with tandem mass-spectrometric detection. The surface structure&nbsp;of CR 5 graphite powder, tricresyl phosphate-based carbon paste electrode and glassy&nbsp;carbon electrode was investigated by scanning electron microscopy.</p>

Les abeilles et les parasitoïdes de pucerons courent le risque d'exposition à des insecticides qui ne leur sont pas destinés. Nos objectifs consistent à évaluer ce risque sur le terrain et à contribuer à mettre au point des tests de toxicité létale et sublétale en laboratoire pour les deux types d'insectes. <br />A Madagascar, nous avons mené une enquête pour déterminer l'impact de pratiques paysannes en matière de protection de cultures d'agrumes sur les abeilles, et une expérimentation en parcelle de choux pour évaluer les effets de traitements insecticides sur les Hyménoptères parasites de pucerons. En France, nous avons déterminé en laboratoire les toxicités aiguës de la deltaméthrine, de la lambda cyhalothrine, du chlorpyriphos éthyle et du pyrimicarbe, pour les abeilles et le parasitoïde de pucerons, Aphidius ervi. Nous avons analysé, chez l'abeille, certaines causes de variabilité des doses létales à 50%. Nous avons également déterminé les effets d'insecticides sur le comportement d'orientation olfactive en olfactomètre chez l'abeille et A. ervi. <br />A Madagascar, le traitement pendant la floraison existe et les apiculteurs constatent des effets négatifs sur leurs ruches. L'expérimentation en parcelle de chou montre que le traitement insecticide contribue à retarder l'action des Hyménoptères parasites de pucerons. <br />En laboratoire, la toxicité varie en fonction du mode de pénétration et de la nature des matières actives. Chez l'abeille, les toxicités par ingestion collective et individuelle ne sont pas toujours comparables. L'importance du phénomène de trophallaxie dans cette différence a été précisée. Ainsi, la valeur de DL50 exprimée en ng/abeille dépend des conditions expérimentales. Les abeilles et A. ervi ayant survécu aux traitements insecticides et testés en olfactomètre, ne montrent pas ou peu de changement de comportement d'orientation vis-à-vis de l'odeur utilisée. Par contre, les abeilles recevant des DL20 et DL50 de deltaméthrine ont une capacité locomotrice réduite. Cette perturbation pourrait avoir des effets non négligeables sur les insectes auxiliaires dans un environnement pollué par les insecticides

Fourteen spore-forming bacterial strains were isolated and screened for entomopathogenic activity. Five displayed toxicity towards the common mealworm, Tenebrio molitor L., (Coleoptera: Tenebrionidae). The majority of the isolates were obtained from insect larvae and insect rich environments. The three bacterial species identified were Bacillus thuringiensis Berliner, Brevibacillus laterosporus Laubach and Bacillus cereus Frankland and Frankland. Bioassays were conducted using T. molitor larvae. The one isolate of B. cereus required the highest concentration of bacterial cells to achieve its LC50, whereas one of the isolates of B. laterosporus required the lowest cell concentration to achieve its LC50. Dose response curves were generated for the five best isolates, which showed that the isolate of B. laterosporus (NDR2) was substantially more toxic than the other isolates. / Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 6 uppsatser.

Made available in DSpace on 2014-06-11T19:22:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-04-25Bitstream added on 2014-06-13T20:10:19Z : No. of bitstreams: 1 jacob_cro_me_rcla.pdf: 1789232 bytes, checksum: 4d1aeb62cf1a6763869b8890da8b652a (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Recentemente as abelhas têm sido devidamente valorizadas como importantes polinizadoras de flores silvestres e cultivadas. A densidade populacional de muitos polinizadores tem diminuído devido, principalmente, à intensificação agrícola e ao uso de pesticidas, prejudicando os serviços de polinização. A metodologia clássica para estimar a toxicidade dos produtos químicos para insetos é determinar a dose letal média (DL50) ou a concentração letal média (CL50), podendo então estabelecer doses que sejam mais seguras aos organismos não-alvo ou benéficos. Além dos efeitos de toxicidade aguda, levando a morte das abelhas, doses subletais dos inseticidas podem provocar alterações comportamentais e fisiológicas nos indivíduos, que ao longo do tempo acarretarão em sérios prejuízos na manutenção da colônia. Um dos inseticidas amplamente utilizado é o fipronil, este atua ligando-se aos receptores do ácido gama-aminobutírico (GABA), interrompendo os canais de cloro, resultando na perda de sinalização inibitória neural. Na literatura pode-se encontrar diversos trabalhos que utilizam como modelo principal a abelha Apis mellifera, porém, é importante ressaltar a diversidade existente entre as abelhas nativas no Brasil, os meliponíneos, e sua participação na conservação da biodiversidade, assim como na polinização de áreas de cultivo, o que torna extremamente importante estudos com essa abelha. Com a finalidade de entender como o fipronil interfere morfo e fisiologicamente em abelhas sem ferrão, a região de interesse deste estudo foram os corpos pedunculados, já que estes são centros cerebrais complexos e tidos como local de convergência multisensorial. Para auxiliar no mapeamento metabólico, utilizou-se como marcador a enzima citocromo oxidase e a enzima caspase-3, técnicas utilizadas na observação de atividade neural... / A few decades the bees are considered an important indicator of high environmental sensitivity, and appreciated as important pollinators of wildflowers and cultivated. The population density of many pollinators have declined to harmful levels to pollination services manly due to agricultural intensification and the use of pesticides. The classic methodology of estimating the effects of chemicals for insects is to determine the median lethal dose (LD50) or median lethal concentration (LC50) that can then establish doses that do not harm non-target organisms or beneficial. Besides the effects of acute toxicity, leading to death bees, sublethal doses of insecticides can cause physiological and behavior changes of individuals over time, resulting in serious harm to maintain the colony. One of the widely used insecticides is fipronil, its acts by binding to gamma-aminobutyric acid (GABA) disrupting chloride channels, resulting in loss of inhibitory neural signaling. In the literature one can find several works using as main bee model Apis mellifera, however, it is important to highlight the diversity of Brazilian native bees, the stingless bees, and their participation in biodiversity conversation, as well as in the pollination of cultivated land. In order to understand how fipronil affect morpho and physiologically the stingless bee S. postica, the region of interest in this study were the mushroom bodies, since these are complex brain centers and used as a place of multisensory convergence. This work established the contact LD50 and Ingestion LC50 to the fipronil insecticide for foragers workers stingless bee Scaptotrigona postica in 0.54ng/bee and 0.24ng/μL of the food after 24 hours, respectively, confirming the high toxicity of this phenylpyrazole, in the groups submitted to contact contamination, were identify morphological... (Complete abstract click electronic access below)

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Sitophilus zeamais is a global important pest-insect, known for the losses that it causes during production and grain storage. One of the main problems caused by synthetic pesticides use is the development of resistant insect populations. Essential oils of plants have been considered a promising alternative to the conventional management of pests insects, however, its direct application has limitations due to the instability of its composition and high volatility. According to this, the technology of nanoformulations production can increase the potential of essential oil use, and its compounds, by increasing the efficiency, and stability of these compounds. The aim of this study was evaluate the lethal and sub lethal effects of Lippia sidoides essential oil, its majoritary compound (thymol), and nanoformulations of essential oil based prototypes, under S. zeamais populations (N = 5) from different regions of Brazil. The chemical composition of the essential oil, and nanoformulation was analyzed by GC/MS/DIC. The completely random design consisted in four replications for each combination of treatment x populations of S. zeamais. Bioassays of acute toxicity were conducted in Petri dishes (6 x 1,5 cm) with 10 unsexed adults. The lethal doses (LD50 and LD90), and the lethal time (LT50) were obtained through topic application bioassays. To the nanoformulation storage efficiency was used the LD95. On the population growth, and grain consume bioassays were used different concentrations of nanoformulations to mass grain treatment. The major compound present in the L. sidoides essential oil was thymol (68.5%). During nanoformulation storage, the concentration of these compound increased, getting to 82% of the essential oil composition. L. sidoides essential oil lethal doses, needed to kill 50% of S. zeamais populations, vary between 7.1 to 19.9 μg mg-1. Jacarezinho, and Maracaju populations were, respectively, the most tolerant and susceptible populations to L. sidoides essential oil. Intermediates susceptibilities were observed to Aracaju, Rio Branco, and Sete Lagoas populations. To thymol LD50 were observed variations between 17.1 to 25.7 μg mg-1. To nanoformulations prototypes (18%) containing L. sidoides essential oil, and thymol were observed LD50 variations between 26.4 to 36 e 20.8 a 27.7 μg mg-1, respectively. L. sidoides essential oil, thymol, and their nanoformulations had a fast action under S. zeamais populations. Lethal times needed to kill 50% of the population vary between 5.8 to 62 hours. In all of those cases, the nanoformulations took longer to cause the same mortality. The nanoformulations caused mortalities higher than 80% of S. zeamais populations of over 210 storage days. Nanoformulations increasing concentrations resulted on intrinsic tax (ri), and grain consume reduction of S. zeamais populations. This study prove that nanoformulations of L. sidoides oil essential based prototypes and its majoritary compound are promising alternatives to the management of S. zeamais once these demonstrated high efficacy, low liberation of the substances, and good storage stability. / Sitophilus zeamais é uma praga de importância mundial que ocasiona danos em grãos durante sua produção e estocagem. Um dos principais problemas da utilização de inseticidas organosintéticos, usados para o controle desta praga, consiste no desenvolvimento de populações de insetos resistentes. Óleos essenciais de plantas tem sido considerados uma boa alternativa ao manejo convencional, porém sua utilização direta apresenta limitações devido à instabilidade de sua composição e a alta volatilidade. Neste sentido, a tecnologia de produção de nanoformulações pode aumentar a potencialidade do uso dos óleos essenciais e seus compostos por aumentar a eficiência e a estabilidade destes compostos. No presente estudo analisamos os efeitos letais e subletais do óleo essencial de Lippia sidoides, de seu composto majoritário (timol) e de protótipos de nanoformulações a base destes compostos sobre populações de S. zeamais (N = 5) provenientes de diferentes regiões do Brasil. A composição química do óleo essencial e da nanoformulação foram analisadas por CG/EM/DIC. O delineamento experimental inteiramente casualizado, consistiu em quatro repetições para cada combinação de tratamento x população de S. zeamais. Bioensaios de toxicidade aguda foram conduzidos em placas de Petri (6 x 1,5 cm) contendo 10 adultos não sexados. As doses letais (DL50 e DL90) e o tempo letal (TL50) foram determinados em bioensaios de aplicação tópica. Para a eficiência do armazenamento das nanoformulações utilizou-se a DL95. Nos bioensaios de crescimento populacional e consumo de grãos foram utilizadas diferentes concentrações das nanoformulações para o tratamento da massa de grãos. O composto majoritário presente no óleo essencial de L. sidoides foi o timol (68,5%). Durante o armazenamento da nanoformulação esse composto aumentou, chegando a até 82% da composição do óleo. As doses letais do óleo essencial de L. sidoides necessárias para matar 50% das populações de S. zeamais variaram de 7,1 a 19,9 μg mg-1. As populações de Jacarezinho e Maracaju foram, respectivamente, a mais tolerante e susceptível ao óleo essencial de L. sidoides. Susceptibidades intermediárias foram observadas para as populações de Aracaju, Rio Branco e Sete Lagoas. O timol apresentou DL50 que variou de 17,1 a 25,7 μg mg-1. Os protótipos das nanoformulações (18%) contendo óleo essencial de L. sidoides e timol apresentaram DL50 que variaram de 26,4 a 36 e 20,8 a 27,7 μg mg-1, respectivamente. O óleo essencial de L. sidoides, o timol e suas nanoformulações atuaram rapidamente sobre as populações de S. zeamais. Os tempos letais necessários para matar 50% das populações variaram de 5,8 a 62 horas. Em todos os casos as nanoformulações demoram mais tempo para causar a mesma mortalidade. As nanoformulações causaram mortalidades superiores a 80% nas populações de S. zeamais até 210 dias de armazenamento. Concentrações crescentes das nanoformulações ocasiononaram redução da taxa intrínseca de crescimento (ri) e do consumo de grãos das populações de S. zeamais. Este trabalho comprova que os protótipos de nanoformulação a base do óleo essencial de L. sidoides e seu composto majoritário são promissores para o manejo de populações de S. zeamais uma vez que demonstraram alta eficácia, liberação lenta das substâncias e boa estabilidade no armazenamento.