ABSTRACT One of the pillars of a no-tillage system is the addition of adequate amounts of residue to keep the soil continuously covered. Cover crops are a tool for supplying the demand for the permanence of residues on the soil surface and releasing nutrients to the soil. However, there is no index that relates these two factors and can reconcile the maximum permanence of crop residues in the soil with the maximum N supply via N mineralization of such residues. This study aimed to assess the effect of different cover crops on the decomposition rate of residues and N release, using the residual biomass quality index (RBQI) to evaluate cover crop systems. The study was conducted in a long-term experiment in a Latossolo Vermelho (Ferralsol, Oxisol) under no-tillage in the two agricultural years 2017/18 and 2018/19. The experiment was in a split-plot factorial scheme with eight winter cover crops and three N rates in randomized blocks with three replications. The cover crop systems were black oat (O), common vetch (V), forage radish (R), white lupine, rye, annual ryegrass, oat + vetch (O+V), and oat + vetch + radish (O+V+R). The N rates applied to the corn in succession were 0, 90, and 180 kg ha-1. The decomposition rate, remaining dry mass (RDM) on the soil surface, N release rate, and N accumulated release (NAR) were assessed using litterbags. Considering NAR and RDM evaluated for up to 105 days, the N release index (NRI) and remaining dry mass index (RDMI) were determined, and the residual biomass quality index (RBQI) was obtained using the product of these variables. The consortia O+V+R and O+V resulted in a decomposition rate and N release rate closer to the rates observed for oats and rye. The NAR was similar to that observed for Fabaceae species, and the RDM was similar or superior to that found for black oat. With these characteristics, the systems in the O+V+R and O+V consortia presented the highest values of RBQI, ranging from 0.61 to 0.90, indicating that RBQI is a potential indicator for choosing cover crop systems that promote greater sustainability of the no-tillage system. The use of N fertilizer in corn did not change the rates of decomposition and N release from the residues of cover crops.

Resumo Introdugao e objetivos : Pouco sabemos acerca da biologia da polinizado de espécies arbóreas tropicais com sistema de polinizado por diversos insetos (DI). Estudamos a biologia floral, o sistema reprodutivo e os visitantes florais de Cupania oblongifolia. M&M : Experimentos e observapóes foram feitos em uma área de Mata Atlántica. Resultados : As flores sao pequenas e esverdeadas e secretam pouco néctar. A espécie é díclina-monóica, mas a antese das flores femininas e masculinas é separada temporalmente nas inflorescencias, com pouca ou sem sobreposipao (i.e., dicogamia sincronizada). A produpao de frutos nao diferiu após polinizapao cruzada, autopolinizapao e condipóes naturais, indicando nao haver autoincompatibilidade nem limitapao polínica. A espécie foi visitada por 87 espécies de Hymenoptera, Diptera, Lepidoptera e Coleoptera. Flores masculinas foram mais visitadas e 20 espécies visitaram os dois morfos florais. A maioria dos visitantes florais foi rara e cerca de 80% das visitas foram de Hymenoptera, em particular abelhas sem ferrao. Duas espécies de Scaptotrigona foram eudominantes. Conclusoes : O fenótipo floral se encaixa na descripao do sistema DI. Muitos insetos foram registrados, mas abelhas sem ferrao predominaram. Meliponini constitui o grupo antófilo mais abundante nas florestas neotropicais, portanto, sistemas de polinizapao associados a elas sao esperados. A partir de nossos resultados se pode projetar que parte das espécies classificadas como DI com base no fenótipo floral e riqueza de visitantes podem estar fortemente associadas a um grupo específico de polinizadores, o que denotaria um menor grau de generalizapao.

Summary Background and aims : We know little about the pollination biology of tropical tree species associated with the pollination system by diverse insects (DI). We studied the floral biology, breeding system, and floral visitors of Cupania oblongifolia. M&M : Experiments and observations were carried out in an area of the Atlantic Forest. Results : The flowers are small and greenish and produce little néctar. The species is diclinous-monoecious but the anthesis of female and male flowers is temporally separated into the inflorescences, with little or no overlap (i.e., synchronized dichogamy). Fruit set did not differ after cross- and self-pollinations and natural conditions, indicating the absence of both self-incompatibility and pollen limitation. Flowers of C. oblongifolia were visited by 87 species of Hymenoptera, Diptera, Lepidoptera, and Coleoptera. Male flowers were more visited and 20 species visited the two morphs. Floral visitors were mostly rare and about 80% of the visits were made by Hymenoptera, mainly stingless bees. Two species of Scaptotrigona were eudominant. Conclusions : The floral phenotype fits on the description of DI systems. Many species of insects were recorded but stingless bees predominated. Meliponini constitutes the most abundant anthophilous group in Neotropical forests, thus pollination systems associated with them are expected. Based on our results, it is possible to forecast that some species classified as DI based on floral phenotype and visitor richness may be strongly associated with a certain group of pollinators, denoting a lower degree of generalization.

ABSTRACT The objective of this work was to evaluate the management of nitrogen fertilization in grains of sorghum inoculated or not with Azospirillum brasilense in single crop or intercropped with Urochloa brizantha (cv. Paiaguás) in the off-season. The experimental design was a completely randomized block design with four replications, in a 2 x 2 x 3 factorial scheme, with sorghum in single-cropped system or intercropped with grass; sorghum seeds inoculated or not with A. brasilense; and N management (application of 100% of the dose at sowing or only in topdressing or split - 30% at sowing and 70% in topdressing) at a dose of 120 kg ha-1 N. Morphological components and sorghum grain yield and productivity of dry matter of the aerial part of the grass and the sorghum were evaluated. The splitting of nitrogen fertilization did not interfere in the yield of sorghum grain straw intercropped with U. brizantha. The intercropping with U. brizantha did not reduce sorghum grain yield. In dry climate conditions in the off-season, inoculation of sorghum seeds cv. Ranchero with A. brasilense increases grain yield.

ABSTRACT Intraspecific floral variations may affect the degree of generalization and efficacy of pollinators, with consequences for plant reproductive success. Such effects could be greater for heterostylous plants because morphological variation can alter reciprocity between morphs. We evaluated the frequency, composition, and efficacy of pollinators, and the reciprocity (measured by population inaccuracy) of Psychotria nuda, a distylous species of Rubiaceae, in a montane forest. Moreover, we assessed the effects of corolla length on reciprocity and reproductive success. We recorded eighteen species of floral visitors, belonging to four functional groups. The frequency of visits differed among groups with butterflies being the most frequent visitors, in contrast to hummingbird-pollinated lowland populations. This difference did not affect reproductive success, since fruit set was similar between these populations. The total population inaccuracy was 21.56 mm2, with inaccuracy of low organs being higher (12.03 mm²) than that of high organs (9.53 mm²). Floral traits may have different effects on the reproductive success of morphs of distylous species; the corolla length of P. nuda only affected the reproductive success of short-styled flowers. Large corollas showed greater reproductive success and lower individual inaccuracies for this morph, indicating compensation for the effects of imperfect reciprocal herkogamy on reproductive success.

ABSTRACT Objective: Abnormalities involving the TGFB1 gene and its receptors are common in several types of cancer and often related to tumor progression. We investigated the role of single nucleotide polymorphisms (SNP) in the susceptibility to cancer, their impact on its features, as well as the role of mRNA expression of these genes in thyroid malignancy. Materials and methods: We genotyped TGFB1, TGFBR1, and TGFBR2 SNPs in 157 papillary thyroid cancer (PTC) patients and 200 healthy controls. Further, we investigated RNA samples of 47 PTC and 80 benign nodules, searching for differential mRNA expression. Results: SNPs rs1800472 and rs1800469 were associated with characteristics of PTC aggressiveness. Effect predictor software analysis of nonsynonymous SNP rs1800472 indicated increasing protein stability and post-translational changes. TGFB1 mRNA expression was upregulated in PTC and downregulated in benign samples, differentiating malignant from benign nodules (p<0.0001); PTC from goiter (p<0.0001); and PTC from FA (p<0.0001). TGFBR1 mRNA expression was upregulated in goiter and PTC, but downregulated in FA, distinguishing PTC from goiter (p=0.0049); PTC from FA (p<0.0001); and goiter from FA (p=0.0267). On the other hand, TGFBR2 was downregulated in all histological types analyzed and was not able to differentiate thyroid nodules. Conclusion: TGFB1 polymorphism rs1800472 may confer greater activity to TGF-β1 in the tumor microenvironment, favoring PTC aggressiveness. Evaluation of TGFB1 and TGFBR1 mRNA levels may be useful to identify malignancy in thyroid nodules.

ABSTRACT One of the alternatives to achieve agriculture with sustainability and reduction in production costs, mainly with fertilizers, is the formation of straw from the previous crop and the use of genus Azospirillum bacteria. The objective of this study was to evaluate the agronomic characteristics and yield of soybean, cultivated in areas under straw of sorghum regrowth inoculated or not with diazotrophic bacteria, single or intercropped with Paiaguás grass under Integrated System of Agricultural Production, in Cerrado region. It was used a complete randomized block design, in a 2 x 2 x 2 factorial arrangement, with four replications, in two agricultural years: with the cultivation of dual-purpose and grain sorghum, single or intercropped with Paiaguás grass, with or without inoculating sorghum seeds with the bacterium Azospirillum brasilense. Soybean production and yield components were evaluated. Inoculation of grain or dual-purpose sorghum seeds with Azospirillum brasilense intercropped with Paiaguás grass, before soybean cultivation, increased the components of production and grain yield of soybean in succession.

ABSTRACT Purpose: The 8th edition of the TNM has been updated and improved in order to ensure a high degree of clinical relevance. A major change in prostate includes pathologically organ - confined disease to be considered pT2 and no longer subclassified by extent of involvement or laterality. The aim of this study was to validate this major change. Materials and Methods: Prostates were step - sectioned from 196 patients submitted to radical prostatectomy with organ confined disease (pT2) and negative surgical margins. Tumor extent was evaluated by a semiquantitative point count method. The dominant nodule extent was recorded as the maximal number of positive points of the largest single focus of cancer from the quadrants. Laterality was considered as either total tumor extent (Group 1) or index tumor extent (Group 2). Time to biochemical recurrence was analyzed with the Kaplan - Meier product limit analysis and prediction of shorter time to biochemical recurrence with Cox proportional hazards model. Results: In Group 1, 43 / 196 (21.9%) tumors were unilateral and 153 / 196 (78.1%) bilateral and in Group 2, 156 / 196 (79.6%) tumors were unilateral and 40 / 196 (20.4%) bilateral. In both groups, comparing unilateral vs bilateral tumors, there was no significant clinicopathological difference, and no significant association with time as well as prediction of shorter time to biochemical recurrence following surgery. Conclusions: Pathologic sub - staging of organ confined disease does not convey prognostic information either considering laterality as total tumor extent or index tumor extent. Furthermore, no correlation exists between digital rectal examination and pathologic stage.

Resumo Recursos florais constituem o elemento de mediação nas interações mutualísticas entre plantas e polinizadores. Em um sistema ótimo, o investimento das flores na produção de recursos é recompensado pelo adequado transporte de pólen entre indivíduos coespecíficos, realizado por cada visitante floral. Porém visitantes podem obter recursos de diferentes modos, com diferentes implicações no processo de polinização e na integridade das flores. A literatura internacional apresenta uma série de termos e conceitos para a diversidade de comportamentos envolvidos em visitas florais impróprias, mas o uso dos termos principais está bem consolidado desde o artigo seminal de David W. Inouye de 1980. Muitos estudos em biologia da polinização no Brasil tratam adequadamente destes conceitos, porém o uso dos termos em língua portuguesa, tais como ladrão e pilhador de néctar, é inconsistente. Aqui são sugeridos termos e definições para uso impróprio de recursos florais, a partir do conceito de visitas legítimas e ilegítimas.

Abstract Floral resources mediate the mutual interactions between plants and pollinators. In an optimal manner, the investment of flowers in the production of resources is rewarded by floral visitors through adequate transport of pollen among conspecific individuals. However, visitors can obtain resources in different ways, with different implications in the pollination process and floral integrity. A range of terms and concepts has been used for the diversity of behaviors involved in floral larceny, but the main terms are consolidated after the seminal paper by David W. Inouye in 1980. Many studies in pollination biology in Brazil deal with these concepts adequately, however, the use of terms in Portuguese such as nectar thief and robber are inconsistent. I here suggest definitions and terms in Portuguese for floral larceny based on the concepts of legitimate and illegitimate visits.

ABSTRACT Plant-pollinator interactions range from obligatory specialists to facultative generalists, and floral morphology and pollination system may not match completely. The floral biology, reproductive system and floral visitors of a species of the tribe Rhipsalideae were investigated with a focus on the consistency between the pollination system and the floral phenotype. Rhipsalis neves-armondii is an obligate xenogamous species, due to self-sterility. Its flowers are white, small and diurnal, and radially symmetrical. These features, along with their small amount of nectar, characterize the flowers as phenotypic generalists. The most frequent pollinators were a solitary oligolectic species of Andrenidae (Rhophitulus solani), two species of Meliponinae (Trigona spinipes and T. braueri) and Apis mellifera. Despite the generalist floral phenotype, the pollination system is functionally specialized, since only small bees performed effective visits. Flowers of R. neves-armondii may represent a case of cryptic floral specialization in which attributes other than morphology act as filters, restricting them to a single functional group of pollinators. Moreover, the four most frequent species of pollinators cover a spectrum ranging from solitary oligolectic to social polylectic bees, including an exotic species. These results illustrate the distinct dimensions of specialization-generalization that may occur in the pollination process of a single species.

ABSTRACT Purpose To find any influence on prognostic factors of index tumor according to predominant location. Materials and Methods Prostate surgical specimens from 499 patients submitted to radical retropubic prostatectomy were step-sectioned. Each transverse section was subdivided into 2 anterolateral and 2 posterolateral quadrants. Tumor extent was evaluated by a semi-quantitative point-count method. The index tumor (dominant nodule) was recorded as the maximal number of positive points of the most extensive tumor area from the quadrants and the predominant location was considered anterior (anterolateral quadrants), posterior (posterolateral quadrants), basal (quadrants in upper half of the prostate), apical (quadrants in lower half of the prostate), left (left quadrants) or right (right quadrants). Time to biochemical recurrence was analyzed by Kaplan-Meier product-limit analysis and prediction of shorter time to biochemical recurrence using univariate and multivariate Cox proportional hazards model. Results Index tumors with predominant posterior location were significantly associated with higher total tumor extent, needle and radical prostatectomy Gleason score, positive lymph nodes and preoperative prostate-specific antigen. Index tumors with predominant basal location were significantly associated with higher preoperative prostate-specific antigen, pathological stage higher than pT2, extra-prostatic extension, and seminal vesicle invasion. Index tumors with predominant basal location were significantly associated with time to biochemical recurrence in Kaplan-Meier estimates and significantly predicted shorter time to biochemical recurrence on univariate analysis but not on multivariate analysis. Conclusions The study suggests that index tumor predominant location is associated with prognosis in radical prostatectomies, however, in multivariate analysis do not offer advantage over other well-established prognostic factors.

RESUMO Introdução: Todos os dias, a ciência busca novas formas de tratar diversas doenças por meio de fármacos que sejam eficientes e viáveis. Desse modo, as alternativas terapêuticas que atendam tal demanda são alvos de estudo. As microemulsões são uma dessas novas alternativas, em razão de suas características farmacodinâmicas e farmacocinéticas peculiares. Objetivo: O objetivo deste estudo foi analisar o potencial anti-inflamatório do óleo de rã-touro puro e em microemulsão usando um modelo experimental de lesão muscular. Métodos: Foram utilizados camundongos machos da linhagem Swiss, divididos em três grupos: controle, microemulsão e óleo de rã-touro puro. Após o pré-tratamento, induziu-se uma lesão muscular na perna dos animais e, em seguida, foram realizadas avaliações da extensão horizontal do edema e comparadas entre os grupos em tempos predeterminados. Depois da avaliação da lesão muscular, realizou-se a dissecção dos músculos gastrocnêmios direitos para análise histológica. Resultados: A microemulsão e o óleo de rã-touro puro apresentaram boa atividade anti-inflamatória, atuando de forma semelhante na redução do edema durante as primeiras duas horas, porém sem significância estatística da 3ª até a 24ª hora depois da indução. Nas análises histológicas, observou-se que no tecido muscular dos animais tratados com a microemulsão houve discreta presença de infiltrado celular e pouco desgaste das fibras musculares quando comparado com o tecido muscular dos animais tratados com o óleo de rã-touro puro. A análise histológica do tecido hepático mostrou sinais de lesão nos lobos hepáticos dos animais do grupo óleo de rã-touro puro, não observada nos animais do grupo microemulsão. Conclusão: A microemulsão apresentou bom potencial anti-inflamatório na fase aguda da resposta inflamatória, atenuando a formação de edema e preservando o tecido muscular contra a ocorrência de lesões e sem indução de lesão no tecido hepático.

ABSTRACT Introduction: Every day science seeks new ways to treat various diseases through drugs that are efficient and viable. Thus, therapeutic alternatives that meet such demand are targets of study. Microemulsions are one of these new alternatives due to their peculiar pharmacodynamic and pharmacokinetic characteristics. Objective: The aim of this study was to analyze the anti-inflammatory potential of microemulsion and pure bullfrog oil using an experimental model of muscle injury. Methods: Male Swiss mice were divided into three groups: control, microemulsion and pure bullfrog oil. After the pre-treatment, a muscle injury was induced in the animals’ leg and subsequently evaluations were carried out in the horizontal extent of edema and compared between the groups at predetermined times. Following evaluation of muscle injury, dissection of the right gastrocnemius muscles was performed for histological analysis. Results: The microemulsion and pure bullfrog oil showed good anti-inflammatory activity, acting similarly in reducing edema during the first two hours, but without statistical significance from the 3rd to the 24th hour after induction. The histological analysis revealed that the muscle tissue of the animals treated with the microemulsion presented mild cellular infiltrate and little wear of muscle fibers when compared with the muscular tissue of animals treated with the pure bullfrog oil. The histological analysis of the hepatic tissue showed signs of injury in the liver lobes of the pure bullfrog oil group, not observed in the microemulsion group. Conclusion: The microemulsion sho-wed good anti-inflammatory potential in the acute phase of the inflammatory response, reducing the formation of edema and preserving muscle tissue against the occurrence of lesions and without inducing injury in hepatic tissue.

RESUMEN Introducción: Todos los días, la ciencia busca nuevas formas para tratar diversas enfermedades por medio de fármacos eficientes y viables. Así, las alternativas terapéuticas que puedan atender esta demanda son objeto de estudio. Las microemulsio-nes son una de estas nuevas alternativas debido a sus características farmacodinámicas y farmacocinéticas únicas. Objetivo: El objetivo de este estudio fue analizar el potencial antiinflamatorio de la microemulsión y el aceite puro de la rana toro utilizando un modelo experimental de lesión muscular. Métodos: Fueron utilizados ratones machos de la cepa Swiss, divididos en tres grupos: control, microemulsión y aceite puro de la rana toro. Después del pretratamiento, se ha creado una lesión muscular en las piernas de los animales y luego se realizaron evaluaciones de la extensión horizontal del edema y comparadas entre grupos en momentos predeterminados. Después de la evaluación de la lesión muscular, se llevó a cabo la disección de los músculos gastrocnemios derechos para el análisis histológico. Resultados: La microemulsión y el aceite de rana toro puro mostraron buena actividad antiinflamatoria, actuando de manera similar para reducir el edema durante las primeras dos horas, pero sin significación estadística desde la tercera hasta la 24.a hora después de la inducción. Los análisis histológicos revelaron que el tejido muscular de los animales tratados con microemulsión presentó presencia moderada de infiltrado celular y poco desgaste de las fibras musculares en comparación con el tejido muscular de los animales tratados con el aceite de rana puro. El análisis histológico del tejido hepático mostró señales de lesión en los lóbulos del hígado de los animales del grupo aceite puro de rana toro, que no fueron observadas en los animales del grupo microemulsión. Conclusión: La microemulsión mostró un buen potencial antiinflamatorio en la fase aguda de la respuesta inflamatoria, la atenuación de la formación de edema y la preservación del tejido muscular en contra de la aparición de lesiones y sin inducción de lesión en el tejido hepático.

ABSTRACT Three different isolates of Pochonia chlamydosporia (Pc-3, Pc-10 and Pc-28) were evaluated in a greenhouse experiment when applied individually and in combinations. A control treatment with no application of isolates of P. chlamydosporia var. chlamydosporia was included, while neither isolates nor nematodes were used in another untreated treatment. One-liter pots were filled with sterilized soil, and each pot was infested with 3 g of rice substrate colonized with the respective isolate plus 3,000 eggs of Meloidogyne javanica. One 'Santa Clara' tomato seedling was transplanted to each pot after fifteen days. None of the isolates (applied individually or in combinations) was able to reduce the number of galls when compared to the control treatment. However, the number of eggs of M. javanica decreased for isolates Pc-10 and mixtures Pc-10 + Pc-3, and Pc-10 + Pc-28 + Pc-3. The association of isolates of P. chlamydosporia var. chlamydosporia did not increase the control of M. javanica when compared to the application of Pc-10 individually.

RESUMEN El experimento se realizó en invernadero, donde se evaluaron tres aislamientos de Pochonia chlamydosporia (Pc-3, Pc-10 y Pc-28), que se aplicaron individualmente y en combinaciones. En el tratamiento testigo no se aplicó P. chlamydosporia var. chlamydosporia al suelo, y también se incluyó un tratamiento testigo sin nematodos. Vasos de un litro de capacidad con suelo esterilizado fueron infestados con 3 g de sustrato de arroz colonizados con el respectivo aislamiento del hongo más 3.000 huevos de M. javanica. Quince días más tarde, se trasplantó en cada vaso una plántula de tomate 'Santa Clara'. Ninguno de los aislamientos del hongo, en forma individual o en mezcla, fueron capaces de reducir el número de agallas en comparación con el tratamiento testigo. Sin embargo, el número de huevos de M. javanica se redujo para el aislamiento Pc-10 y las combinaciones de Pc-10 + Pc-3 y Pc-10 + Pc-28 + Pc-3. La asociación de los aislamientos de P. chlamydosporia var. chlamydosporia no aumentó el control de M. javanica en comparación con la aplicación de Pc-10 individualmente.

RESUMO A aplicação de um bionematicida à base de clamidósporos de Pochonia chlamydosporia (Pc-10) pode se tornar uma importante estratégia para reduzir os danos causados por Meloidogyne incognita em cenoura. Baseado nessa perspectiva, o efeito nematicida de 0; 0,5; 1,0; 1,5; 2,0; 2.5 e 3,0 kg ha -1 de Pc-10 foi avaliado em área de produção de cenoura cv. Juliana em condições de campo. A produtividade de cenoura e a população do nematoide foram influenciados por doses crescentes de Pc-10. A aplicação de 3,0 kg ha-1 de Pc-10 aumentou a produção de raízes comerciais de cenoura em 41,7% comparada com aquela obtida na testemunha não tratada, enquanto que a produção de raízes não-comerciais e a população do nematoide no solo foram reduzidos em 48,7% e 61,4%, respectivamente. A aplicação de 3,0 kg ha -1 de Pc-10 reduz a população de M. incognita e aumenta a qualidade e a produtividade das raízes de cenoura.

ABSTRACT The application of a bionematicide based on chlamydospores of Pochonia chlamydosporia (Pc-10) can be an important strategy for reducing the damage caused by Meloidogyne incognita on carrot. Based on this perspective, the nematicidal effects of 0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 kg ha -1 of Pc-10 were evaluated on carrot cv. Juliana under field conditions. Carrot yield and nematode population were influenced by increasing doses of Pc-10. The application of 3.0 kg ha-1 of Pc-10 increased the marketable production of carrot roots by 41.7% compared to the untreated control, whereas the production of unmarketable roots and the nematode population in the soil were reduced by 48.7% and 61.4%. The application of 3.0 kg ha -1 of Pc-10 reduces M. incognita population and improves carrot quality and yield.

RESUMO A doença de Chagas, causada pelo Trypanosoma cruzi, possui uma ampla distribuição na América do Sul, e tem como principal método de controle a eliminação de triatomíneos. Apresenta-se aqui a distribuição geográfica e a taxa de infecção natural por T. cruzi de triatomíneos coletados e avaliados de 2008 a 2013, no sudoeste da Bahia. Os triatomíneos foram capturados nas áreas intradomiciliares e peridomiciliares de cinco cidades localizadas no sudoeste da Bahia, identificados e analisados quanto à presença de tripanossomatídeos em suas fezes. Durante o período de estudo o número de pacientes com suspeita de doença de Chagas aguda foi recuperado a partir do Sistema de Informação de Agravos de Notificação (SINAN). 8966 triatomíneos foram capturados e identificados como pertencentes a oito espécies. Vinte e seis apresentaram-se infectados, sendo Triatoma sordida o que mostrou maior percentagem de infecção pelo T. cruzi. Tremedal foi a cidade com o maior número de casos de doença de Chagas aguda relatado pelo SINAN. Todas as cidades apresentaram triatomíneos infectados com o T. cruzi, por isso, existe um risco considerável de transmissão vetorial da doença de Chagas no sudoeste da Bahia, evidenciando a necessidade de programas de controle de vetores de transmissão e medidas de vigilância preventiva.

ABSTRACT Chagas disease, caused by the Trypanosoma cruzi, has a wide distribution in South America, and its main method of control is the elimination of triatomines. It is presented here the geographic distribution and the rate of natural infection by T. cruzi of triatomines collected and evaluated from 2008 to 2013 in southwest of Bahia. Triatomines were captured in the intradomiciliary and peridomiciliary areas of five cities located in the southwest of Bahia state, identified, and analyzed for the presence of trypanosomatids in their feces. During the study period the number of patients suspected for acute Chagas disease was recovered from the Notifiable Diseases Information System (SINAN). 8966 triatomines were captured and identified as belonging to eight species. Twenty-six presented themselves infected, being Triatoma sordida the most abundant and with the highest percentage of infection by T. cruzi. Tremedal was the city with the highest number of cases of acute Chagas' disease reported to SINAN. All cities showed triatomines infected with T. cruzi, so there is considerable risk of vectorial transmission of Chagas disease in the southwestern Bahia state, evidencing the need for vector transmission control programs and preventive surveillance measures.