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BACKGROUND: Intercropping is commonly implemented as a way of promoting sustainable agriculture. Some of the benefits of intercropping include improving resource-use efficiency and soil quality as well as promoting pest control. As for pest control, intercropping can often engender pest repellency/confusion and promote natural biological control. Nevertheless, intercropping is not always a win-win strategy for pest management, with chances of sometimes either favoring or hampering pests and their natural enemies. Brazilian farmers commonly row-intercrop maize with brachiaria with the intent of forming a grass pasture for the feeding of livestock after maize harvest. However, very little is known about whether this intercropping can influence key pests and natural enemies in the maize agroecosystem. The overall aim of this study was to investigate how multiple groups of maize pests and natural enemies respond in terms of temporal abundance to this intercropping. RESULTS: Defoliation caused by caterpillars was higher in the intercropping treatment. Intercropping appeared to promote Dalbulus maidis while hampering aphids and Diabrotica speciosa. In general, the abundance of natural enemies was favored by intercropping. There was a reduction in maize productivity (i.e. fresh weight) in the intercropping treatment. Most results were season dependent. CONCLUSION: We believe that by considering together the pros and cons of intercropping maize and brachiaria in terms of pest management and soil conservation/fertility, the benefits of implementing this intercropping shall still outweigh its potential challenges. Nevertheless, the results and ensuing recommendations should be considered under the context of time and arthropod species. © 2022 Society of Chemical Industry.

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Prisoners in most countries have a higher prevalence of HCV than the general population, but their access to treatment is very limited. Our aim was to evaluate a pilot programme using the ECHO model to enhance linkage to care in patients with HCV in 3 Argentinean prisons between October 2018 and January 2020. All inmates were invited to participate, and data were collected through a personal interview. We then estimated HCV prevalence with dried blood spot and performed a logistic regression analysis to identify risk behaviours associated with HCV infection. Finally, HCV management was assessed and monitored through ECHO. Overall, 1141 inmates agreed to participate, representing 39.7% of the total prison population. Anti-HCV prevalence was estimated at 1.58% (CI 0.93; 2.48), being significantly higher in women 2.98% (CI 1.4;5.6) than in men 1.07% (CI 0.5; 2.0); P = .03. Patients with anti-HCV were significantly older than those who tested negative, 42.3 years (CI 37.6;47.1) vs 30.1 years (CI 30.6;31.2), P < .001, respectively. Multiple logistic regression analysis, identified age OR 1.07 (CI 1.03;1.12, P = .001), history of sexually transmitted disease OR 3.08 (CI 0.97;9.82, P = .057) and intravenous drug use OR 12.6 (CI 3.31;48.53, P < .001) as risk factors associated with anti-HCV. Treatment was initiated in all the patients with specialist physician support utilizing ECHO model. In conclusion, our pilot study reported a low prevalence of anti-HCV in the studied population. Incarceration provides an ideal opportunity for testing and treating HCV. ECHO model arises as a useful tool to support assessment and treatment for inmates with chronic HCV.

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Changes in spacing within rows may alter the morphology of the coffee plant by affecting the physiological constituents of its productivity. Even though some common plant responses to crop spacing variation are known, there is yet no scientific evidence that elucidates the effects of decreased spacing on the source-sink relation in plagiotropic branches and, its association with both productivity and eco-physiological aspects of coffee leaves, mainly for new coffee cultivars in the Brazilian savannah. The aim of this work was to characterize the morphophysiological responses of Coffea arabica L. cultivars subjected to different spacing between plants within rows. Four Arabica coffee cultivars (Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32, and Tupi RN IAC 1669-13) were transplanted in January 2010. A row spacing of 0.40, 0.50, 0.60, 0.70, and 0.80 m was adopted between plants, maintaining a 3.80-m constant between rows. A randomized block design with four replicates was applied. During the experimental period, several morphophysiological characteristics of plagiotropic fruiting branches were evaluated in the months of April and December in 2013 and, in April 2014. The evaluation was conducted based on two canopy positions; canopy toward the rows, representing low exposure to light or toward the inter-row spacing, representing high light exposure. Leaf gas exchange, chlorophyll fluorescence, and photosynthetic pigments levels were minimally or not at all affected by changing either the coffee cultivars or plant spacing. During the first evaluation, the leaf-to-fruit-ratio linearly increased, regardless of the cultivar. Light-exposed branches showed higher content of carotenoids and chlorophyll a in leaves and lower leaf-to-fruit-ratio as compared to those within the plant canopy.[...](AU)

A variação do espaçamento dentro da linha de plantio pode interferir na morfologia do cafeeiro, alterando seus componentes de produtividade. Apesar de algumas respostas gerais à variação do espaçamento serem conhecidas, nenhum trabalho anteriormente demonstrou como e quanto a redução do espaçamento na linha altera a relação fonte: dreno de ramos plagiotrópicos, associando-a com os componentes de produtividade e com aspectos ecofisiológicos foliares. Isso considerando as modernas tecnologias e cultivares em uso no Cerrado. O objetivo deste trabalho foi quantificar as respostas morfofisiológicas em ramos plagiotrópicos de cultivares de Coffea arabica L. submetidas a diferentes espaçamentos na linha de plantio. Os cultivares Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32 e Tupi RN IAC 1669-13 foram plantados em janeiro de 2010, no espaçamento de 3,80 m entre linhas, adotando-se os espaçamentos de 0,40, 0,50, 0,60, 0,70 e 0,80 m entre plantas na linha. O delineamento foi em blocos casualizados, com quatro repetições. Em abril e dezembro de 2013 e, também, em abril de 2014, foram feitas diversas avaliações morfofisiológicas em ramos produtivos (com carga pendente) posicionados no sentido da linha ou perpendicularmente a esta (portanto, menos ou mais exposto à luz, respectivamente). As trocas gasosas, os parâmetros de fluorescência e os níveis de pigmentos foram pouco ou nada afetados pelas cultivares e espaçamentos. A razão área foliar: fruto, em abril de 2013, aumentou linearmente com a redução do espaçamento, independentemente de cultivares. Em ramos mais expostos os níveis de carotenóides e clorofila a foram superiores, ao passo que a razão área foliar: fruto foi inferior, em comparação a ramos mais internos.[...](AU)

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Changes in spacing within rows may alter the morphology of the coffee plant by affecting the physiological constituents of its productivity. Even though some common plant responses to crop spacing variation are known, there is yet no scientific evidence that elucidates the effects of decreased spacing on the source-sink relation in plagiotropic branches and, its association with both productivity and eco-physiological aspects of coffee leaves, mainly for new coffee cultivars in the Brazilian savannah. The aim of this work was to characterize the morphophysiological responses of Coffea arabica L. cultivars subjected to different spacing between plants within rows. Four Arabica coffee cultivars (Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32, and Tupi RN IAC 1669-13) were transplanted in January 2010. A row spacing of 0.40, 0.50, 0.60, 0.70, and 0.80 m was adopted between plants, maintaining a 3.80-m constant between rows. A randomized block design with four replicates was applied. During the experimental period, several morphophysiological characteristics of plagiotropic fruiting branches were evaluated in the months of April and December in 2013 and, in April 2014. The evaluation was conducted based on two canopy positions; canopy toward the rows, representing low exposure to light or toward the inter-row spacing, representing high light exposure. Leaf gas exchange, chlorophyll fluorescence, and photosynthetic pigments levels were minimally or not at all affected by changing either the coffee cultivars or plant spacing. During the first evaluation, the leaf-to-fruit-ratio linearly increased, regardless of the cultivar. Light-exposed branches showed higher content of carotenoids and chlorophyll a in leaves and lower leaf-to-fruit-ratio as compared to those within the plant canopy.[...]

A variação do espaçamento dentro da linha de plantio pode interferir na morfologia do cafeeiro, alterando seus componentes de produtividade. Apesar de algumas respostas gerais à variação do espaçamento serem conhecidas, nenhum trabalho anteriormente demonstrou como e quanto a redução do espaçamento na linha altera a relação fonte: dreno de ramos plagiotrópicos, associando-a com os componentes de produtividade e com aspectos ecofisiológicos foliares. Isso considerando as modernas tecnologias e cultivares em uso no Cerrado. O objetivo deste trabalho foi quantificar as respostas morfofisiológicas em ramos plagiotrópicos de cultivares de Coffea arabica L. submetidas a diferentes espaçamentos na linha de plantio. Os cultivares Catuaí Vermelho IAC 144, Catuaí Amarelo IAC 62, Catuaí Amarelo IAC 32 e Tupi RN IAC 1669-13 foram plantados em janeiro de 2010, no espaçamento de 3,80 m entre linhas, adotando-se os espaçamentos de 0,40, 0,50, 0,60, 0,70 e 0,80 m entre plantas na linha. O delineamento foi em blocos casualizados, com quatro repetições. Em abril e dezembro de 2013 e, também, em abril de 2014, foram feitas diversas avaliações morfofisiológicas em ramos produtivos (com carga pendente) posicionados no sentido da linha ou perpendicularmente a esta (portanto, menos ou mais exposto à luz, respectivamente). As trocas gasosas, os parâmetros de fluorescência e os níveis de pigmentos foram pouco ou nada afetados pelas cultivares e espaçamentos. A razão área foliar: fruto, em abril de 2013, aumentou linearmente com a redução do espaçamento, independentemente de cultivares. Em ramos mais expostos os níveis de carotenóides e clorofila a foram superiores, ao passo que a razão área foliar: fruto foi inferior, em comparação a ramos mais internos.[...]

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Com a expansão do cultivo de soja resistente ao glyphosate, observa-se aumento considerável tanto do uso desse herbicida como do número de formulações comerciais à base deste princípio ativo. Objetivou-se, portanto, avaliar o efeito de seis formulações de glyphosate (Roundup Original®, Trop®, Roundup Ultra®, Roundup WG®, Roundup Transorb R® e Zapp Qi®) em parâmetros fotossintéticos, colonização micorrízica e produtividade de soja (TMG 125 Roundup Ready), na região do Alto Paranaíba. Utilizou-se do delineamento em blocos casualizados, com quatro repetições. Uma única aplicação dos herbicidas (720 g e.a. ha-1) foi realizada entre os estádios V2-V3. Aos 3 e 7 dias após a aplicação dos tratamentos (DAT), foram feitas avaliações instantâneas de trocas gasosas entre 08:00 e 9:00 h, em folíolos completamente expandidos. Em seguida, o desempenho fotossintético foi avaliado por meio de curvas de luz (taxa de assimilação líquida de CO2 vs irradiância). A colonização micorrízica, altura de plantas e massa seca da parte aérea foram avaliadas quando as plantas de soja atingiram o estádio R2. Além disso, avaliaram-se o peso de sementes e produtividade de soja. As diferentes formulações de glyphosate não afetaram as trocas gasosas das plantas de soja, nem a eficiência dessas plantas na utilização da irradiância, razão pela qual também não se observou diferenças significativas na massa seca da parte aérea, colonização micorrízica e produtividade de soja.

The expansion of soybean resistant to glyphosate has caused considerable increase in the use of this herbicide as well as the number of formulations based on this active ingredient. The aim is evaluate the effect of six formulations of glyphosate (Roundup Original®, Trop®, Roundup Ultra®, Roundup WG®, Roundup Transorb R® e Zapp Qi®) in photosynthetic parameters, mycorrhizal colonization and soybean yield (TMG 125 Roundup Ready), in the Alto Paranaíba. It was used a randomized block design with four replications. A single application of herbicides (780 g a.e ha-1) was performed between stages V2-V3. At 3 and 7 days after application of the treatments were evaluated instantaneous gas exchange between 08:00 and 9:00 am, in fully expanded leaflets. Then, the photosynthetic performance was evaluated by means of light curves (CO2 assimilation rate vs. irradiance). The mycorrhizal colonization, plant height and shoot dry matter were assessed when the soybean plants reached the stage R2. In addition, we evaluated the weight of seeds and soybean yield. The different formulations of glyphosate did not affect gas exchange of soybean plants and the efficiency of these plants in the use of irradiance, therefore also no observed significant differences in shoot dry weight, mycorrhizal colonization and soybean yield.

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Objetivou-se neste trabalho estimar o potencial de lixiviação dosherbicidas utilizados nas áreas de agricultura intensiva da regiãodo Alto Paranaíba (MG). Utilizou-se o Fator de Atenuação (AF)para estimar as frações perdidas por lixiviação nos primeiros80 cm do perfi l de solo. As avaliações foram realizadas com basenas propriedades físico-químicas dos ingredientes ativos obtidas devárias fontes de dados, combinadas com os atributos de LatossoloVermelho distroférrico. As amostras de solo, coletadas em trêspontos representativos no município de Rio Paranaíba (MG),foram submetidas às determinações de teor de carbono orgânico,densidade do solo e capacidade de campo. Utilizou-se o softwareARAquá como ferramenta auxiliar nos cálculos. Os herbicidasdiurom, linurom, alacloro, trifl uralina, fl uazifope-p-butílico, paraquate,glifosato, lactofem e oxifl uorfem apresentaram, no solo estudado,mobilidade muito baixa. Evidenciaram maior potencial de lixiviação,na seguinte ordem, os produtos: imazetapir, fomesafem, metribuzim,nicossulfurom, atrazina, ametrina, clorimurom-etílico e bentazona.Essas moléculas apresentam risco de contaminação de águassubterrâneas e devem ser consideradas em etapas posteriores deavaliação de impacto ao ambiente.

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Coffee (Coffea arabica L.) plants were grown in small (3-L), medium (10-L) and large (24-L) pots for 115 or 165 d after transplanting (DAT), which allowed different degrees of root restriction. Effects of altered source : sink ratio were evaluated in order to explore possible stomatal and non-stomatal mechanisms of photosynthetic down-regulation. Increasing root restriction brought about large and general reductions in plant growth associated with a rising root : shoot ratio. Treatments did not affect leaf water potential or leaf nutrient status, with the exception of N content, which dropped significantly with increasing root restriction even though an adequate N supply was available. Photosynthesis was severely reduced when plants were grown in small pots; this was largely associated with non-stomatal factors, such as decreased Rubisco activity. At 165 DAT contents of hexose, sucrose, and amino acids decreased in plants grown in smaller pots, while those of starch and hexose-P increased in plants grown in smaller pots. Photosynthetic rates were negatively correlated with the ratio of hexose to free amino acids, but not with hexose content. Activities of acid invertase, sucrose synthase, sucrose-P synthase, fructose-1,6-bisphosphatase, ADP-glucose pyrophosphorylase, starch phosphorylase, glyceraldehyde-3-P dehydrogenase, PPi : fructose-6-P 1-phosphotransferase and NADP : glyceraldehyde-3-P dehydrogenase all decreased with severe root restriction. Glycerate-3-P : Pi and glucose-6-P : fructose-6-P ratios decreased accordingly. Photosynthetic down-regulation was unlikely to have been associated directly with an end-product limitation, but rather with decreases in Rubisco. Such a down-regulation was largely a result of N deficiency caused by growing coffee plants in small pots.