ABSTRACT The application of flumioxazin and imazethapyr can affect the interactions between rhizobia and soybean in the rhizosphere. However, it remains unclear the effect of both herbicides, even when applied in mixture, on early nodulation and biological N fixation (BNF) in soybean, mainly related to some important biochemical traits in nodules. This study assessed the effect of flumioxazin, imazethapyr and their mixture on early nodulation and BNF in rhizosphere of soybean. The plant emergence, early nodulation, growth, and N accumulation were evaluated in soybean grown in sandy and clayey soils. The leghemoglobin content and glutamine synthetase (GS) activity were also assessed in fresh nodules. Individually, flumioxazin and imazethapyr did not affect the plant emergence, nodulation and N accumulation in soybean, while the mixture decreased significantly these parameters. Also, the values of leghemoglobin content and GS activity did not decrease with the application of the herbicides individually. The application of herbicides imazethapyr and flumioxazin separately negatively influenced the growth of soybean, while they do not influence the nodulation and N accumulation. However, the use of these herbicides in mixture can negatively influence the early nodulation and N fixation by native rhizobia.

Abstract Hyptis australis is a species of the Lamiaceae family, endemic to the Atlantic Forest, whose conservation status is critical and its potential benefits for the ecosystem and society are still unknown. For rescue and conservation purposes (ex situ/in situ), the need arises to generate a vegetative propagation protocol to facilitate and increase the availability of plants. With this objective, factors such as the type of substrate, type of stake and hormone were studied. One-year-old plants were used, obtained from seeds harvested from plants located in the southern region of the province of Misiones (Argentina). Apical and subapical cuttings were used in two trials, the first studied the feasibility of inducing adventitious roots in pine bark, sand and perlite substrates. In the second test, the induction of rhizogenesis was evaluated in cuttings treated for 30 minutes with a solution of 100 mg.kg-1 of naphthalenacetic acid (ANA) or indole butyric acid (IBA) in pine bark. The best results were obtained in the sand substrate and in the terminal stakes. ANA was the hormone that generated the highest percentage of apical cuttings (80.00±14.14%) and subapical (84.00±16.73%) with roots. In the subapical cuttings the sprouting percentage was higher in both experiments. The probability that an H. australis cuttings will develop adventitious roots depends on the type of substrate, but the addition of ANA notably improves the rooting percentage.

Resumen Hyptis australis es una especie de la familia Lamiaceae, endémica del Bosque Atlántico, cuyo estado de conservación es crítico y se desconoce aún sus beneficios potenciales para el ecosistema y la sociedad. Con fines de rescate y conservación (ex situ/in situ), se plantea como necesidad, generar un protocolo de propagación vegetativa para facilitar y aumentar la disponibilidad de plantas. Con este objetivo, se estudiaron factores como el tipo de sustrato, tipo de estaca y hormona. Se utilizaron plantas de un año de edad, obtenidas de semillas cosechadas de las plantas ubicadas en la región sur de la provincia de Misiones (Argentina). Estacas apicales y subapicales fueron utilizadas en dos ensayos, en el primero se estudió la factibilidad de inducir raíces adventicias en los sustratos corteza de pino, arena y perlita. En el segundo ensayo, se evaluó la inducción de rizogénesis en estacas tratadas durante 30 minutos con una solución de 100 mg.kg -1 de ácido naftalenacetico (ANA) o ácido indolbutirico (AIB) en corteza de pino. Los mejores resultados se obtuvieron en el sustrato arena y en las estacas terminales. El ANA fue la hormona que generó mayor porcentaje de estacas apicales (80.00±14.14 %) y subapicales (84.00±16.73 %) con raíces. En las estacas subapicales el porcentaje de brotación fue mayor en ambos experimentos. La probabilidad de que una estaca de H. australis desarrolle raíces adventicia depende del tipo de sustrato, pero la adicción de ANA mejora notablemente el porcentaje de enraizamiento.

Abstract The assessment of ecosystem functions in Cerrado is important to implement practices of conservation. Recently, a ‘rapid ecosystem function assessment’ (REFA) for measuring ecosystem functions has been proposed and tested as a suitable method. Thus, this study aimed to assess the proxies of ecosystem functions of three physiognomies of Cerrado through REFA. This method was applied in three different preserved physiognomies of Cerrado from Northeastern, Brazil, namely: Campo Graminoide (CG), Cerrado Stricto Sensu (CSS), and Cerradão (CD). All proxies for the selected ecosystem functions differed between sites and seasons. The above- and belowground primary productivity and microbial biomass C were higher in CD than in CSS and CG. The above- and belowground secondary productivity and decomposition were higher and similar in CD and CSS as compared to CG. The principal component analysis explained 89.8% of the data variation and clustered the majority of ecosystem functions with CD, in both seasons and CSS in the wet season. The proxies of ecosystem functions measured through REFA showed differences between the physiognomies of Cerrado. Since each physiognomy of Cerrado presents different plant richness and diversity, and soil conditions, these characteristics contribute to influencing multiple ecosystem functions.

Resumen Hedeoma teyucuarensis es una especie microendémica del único fragmento del bioma Cerrado de la Argentina desarrollado sobre areniscas. Se encuentra en peligro crítico dado que es utilizada en medicina popular para combatir los parásitos intestinales. El objetivo del presente estudio es evaluar la factibilidad de obtener plantas madre de H. teyucuarensis a partir de estacas, empleando diferentes concentraciones de ácido 1-naftalenacético (ANA) en arena, perlita y corteza de pino. Se cosecharon estacas de plantas ubicadas en su área de distribución natural (San Ignacio, Misiones, Argentina). Posteriormente, del material vegetal cosechado, se obtuvieron estacas apicales y subapicales de un largo de 7 cm. Las bases de estas son sumergidas en una solución de ANA en las dosis 0, 100 y 250 mg.kg-1, durante 30 minutos y luego en una solución fúngica por 20 minutos. Las estacas son colocadas en macetas de 200 cm3, que contienen como sustrato, arena, perlita y corteza de pino. El mayor porcentaje de enraizamiento se obtiene en las estacas del tratamiento testigo. La concentración de ANA no afecta el porcentaje de enraizamiento, pero si en el número de raíces. Este trabajo ha demostrado que el tipo de estaca como de sustrato utilizado afecta el enraizamiento y por ende la obtención de plantas. Este estudio aporta una metodología de propagación vegetativa para obtener plantas, el cual puede servir para conservar esta especie en peligro.

Abstract Hedeoma teyucuarensis is a microendemic species of the only fragment of the Cerrado Biome of Argentina developed on sandstones. It is critically endangered because it is used in folk medicine to combat intestinal parasites. The aim of the present study is to evaluate the feasibility of obtaining H. teyucuarensis mother plants from cuttings, using different concentrations of 1-naphthaleneacetic acid (NAA) in sand, perlite, and pine bark. Cuttings are harvested from plants located in its natural distribution area (San Ignacio, Misiones, Argentina). Subsequently, apical and subapical cuttings 7 cm long are obtained from the harvested plant material. The bases of these are immersed in a solution of NAA at doses of 0, 100 and 250 mg/kg-1 for 30 minutes and then in a fungal solution for 20 minutes. The cuttings are placed in 200 cm3 pots containing sand, perlite, and pine bark as substrate. The highest percentage of rooting is obtained in the cuttings of the control treatment. The concentration of NAA did not affect the rooting percentage but did affect the number of roots. This work has shown that the type of stake and substrate used affects rooting and therefore the obtaining of plants. This study provides a methodology of vegetative propagation to obtain plants, which can be used to conserve this endangered species.

Abstract The purpose of plant health and protection is to generate actions for the control of agricultural pests and diseases, the use of pesticides and the determination of phytosanitary status for commercialization within the framework of food safety. However, plant protection as a normative and regulatory instrument has remained on the global and national scale, when pest management is mainly local. There is an institutional and territorial disarticulation regarding the regulation of pesticides. At a global level, Integrated Pest Management (IPM) was recognized as the public policy of pest management and control, at the local level, this structure did not arrive and is not applied due to the lack of a phytosanitary extension model. This means that the only means to eradicate agricultural pests is the indiscriminate use of pesticides, some prohibited, in other countries due to the significant effects on human health and the environment. However, Mexico allows its distribution and commercialization. The research was developed in the agricultural valley of Rioverde and Ciudad Fernández, two municipalities in the state of San Luis Potosí, considered an area of great importance in agricultural terms, above all, due to its high productivity of orange cultivation. It has also been characterized by the use of dangerous pesticides, which has affected the health of the population and concern for its most important resource, water. Due to the aforementioned, this work aimed to demonstrate that territorial governance problems constitute the most important challenge to face and solve the pesticide problem in Mexico. The methodological process had a qualitative and quantitative approach based on the extension of innovation through geotechnologies for the identification of areas and plots with greater use of pesticides to combat pests and diseases of crops. The methodological process consisted of two phases: a) the sampling was through the mobile application called “Agroquímicos LAGES” developed by the National Laboratory of Geoprocessing of Phytosanitary Information (LaNGIF), this process was in charge of students of Engineering in Agricultural Innovation Sustainable Institute of the Higher Technological Institute (ITS) and of Agroindustrial Engineering and Agronomic Engineering in Phytotechnics of the Autonomous University of San Luis Potosí (UASLP), generating a database with 22,939 data on producers, crops and pesticides; b) The data analysis consisted, first of all, in making a distinction between permitted and restricted pesticides detected in the area based on the Registry of Canceled Pesticides and Nutrients of the Federal Commission for Protection against Sanitary Risks (COFEPRIS) for later apply the non-parametric statistical hypothesis test Chi square (X2) and thus determine the existence of association between the level of education, type of crop (vegetables, corn and orange) and the taxonomic group with pesticides, likewise an analysis was carried out Multicriteria to identify and classify, through spatial nodes, the areas with restricted pesticide application and in turn, the characterization of the producers, the cultivation and the land tenure. As a result, it was obtained that the “agronomic houses” control the management of pesticides, which are small private businesses that face lax agricultural, environmental and health policies, and act outside the state and national regulations; In statistical terms, the crops with the highest frequency of restricted pesticide use were corn and vegetables, and in spatial terms, restricted pesticides such as: Diazinon, Glyphosate, Carbofuran, Chlorpyrifos Ethyl, Methamidophos, Metomil and Monocrotophos are applied in the El Refugio ejido. all Highly Hazardous Pesticides (HHP). Given this scenario, it is considered necessary to generate inventories according to the phytosanitary status of pests and diseases, in addition to diagnoses on the use of pesticides at a local scale. Without this, actions aimed at solving, remedying and reducing the economic, environmental and health problems caused by said disarticulation are difficult. The methodological triad that consisted of the use of geotechnologies, statistical analysis and spatial analysis allows us to generate diagnoses and monitor the use and management of pesticides, at low cost and at a local scale. It is important to note that the identification of the areas with the greatest application of restricted pesticides does not have the motivation to transfer responsibility to the producer. On the contrary, they are intended to direct phytosanitary extension actions to specific sites.

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Lima bean (Phaseolus lunatus) is an important species of the genus Phaseolus for human consumption in tropical regions. The seeds are important source of protein for people from South America, Africa and Mexico. In addition, as a legume plant, lima bean presents the ability to perform the biological nitrogen fixation (BNF) through the symbiosis with nitrogen-fixing bacteria. The studies about diversity and efficiency of lima bean-rhizobia symbiosis have increased worldwide, mainly in Latin America. These studies have shown Bradyrhizobium and Rhizobium as the main symbionts, although Sinorhizobium, Mesorhizobium and Allorhizobium have been found associated with lima bean. Also, there is a large variation in the efficiency of N fixation by the current isolates of rhizobia and some rhizobia have presented high capability for fixing N. This review aims to explore the studies about diversity and efficiency of rhizobia in symbiosis with lima bean.

El frijol de lima (Phaseolus lunatus) es una especie importante del género Phaseolus para consumo humano en regiones tropicales. Las semillas son una fuente importante de proteínas para las personas de América del Sur, África y México. Además, como leguminosas, el frijol de lima presenta la capacidad de realizar la fijación biológica de nitrógeno (BNF) a través de la simbiosis con bacterias fijadoras de nitrógeno. Los estudios sobre la diversidad y la eficiencia de la simbiosis de frijol de lima-rizobio han aumentado en todo el mundo, principalmente en América Latina. Estos estudios han demostrado que Bradyrhizobium y Rhizobium son los principales simbiontes, aunque Sinorhizobium, Mesorhizobium y Allorhizobium se han asociado al frijol de lima. Además, existe una gran variación en la eficacia de la fijación de N por los aislamientos actuales de rizobios y algunos rizobios han presentado una alta capacidad para reparar N. Esta revisión tiene como objetivo explorar los estudios sobre la diversidad y la eficacia de rizobios en simbiosis con frijol lima.

RESUMO: Este estudo avaliou a resposta do feijão-fava (Phaseolus lunatus L.) a aplicação de lodo de curtume compostado na nodulação, absorção de N e crescimento. Durante oito anos, o composto foi aplicado em doses de: 0, 2.5, 5, 10, e 20 Mg ha-1 (base seca). As plantas de feijão-fava mostraram maior nodulação nos tratamentos com o composto. Entretanto, os nódulos encontrados nestes tratamentos apresentaram menor biomassa, tamanho e diversidade do que os observados no tratamento sem composto. A acumulação de N aumentou com a aplicação da maior dose do composto (20 Mg ha-1), enquanto que houve um aumento nos teores de crômio na parte aérea com o aumento das doses do composto. Desta forma, o uso do lodo de curtume compostado, em longo prazo, aumenta a acumulação de crômio, aumentando a nodulação, enquanto diminui a diversidade de rizóbios nos nódulos.

ABSTRACT: This study evaluated the responses of lima bean (Phaseolus lunatus L.) to application of composted tannery sludge on nodulation, N uptake and plant growth. For eight years, the compost was applied at rates of: 0, 2.5, 5, 10, and 20 Mg ha-1 (dry basis). Plants of lima bean showed higher nodulation in treatments with compost; however, nodules reported in these treatments presented lower biomass, size and diversity than those reported in treatment without compost. Accumulation of N increased with the application of the highest rate (20 Mg ha-1), while there was an increase in chromium content in shoot with the increase in compost rates. Thus, the use of composted tannery sludge, in long-term, increases the accumulation of chromium in plants, increasing nodulation, while decrease rhizobia diversity in nodules.

Abstract: Different physiognomies across the Cerrado could influence the microbial C:N:P ratio in the soil since these physiognomies present different abundance and diversity of plant species. Thus, the aim of this study was to evaluate the microbial C:N:P ratio in soil across three different physiognomies of Cerrado in the Northeast, Brazil, namely campo graminóide (dominance of grasses), cerrado stricto sensu (dominance of grasses, shrubs, low trees, and woody stratum), and cerradão (dominance of woody stratum). Campo graminóide was characterized by lower values of total organic C, N, microbial C:P, N:P, and soil C:N. Cerrado stricto sensu presented average values for most of the measured parameters, while cerradão presented higher values of microbial C, N, P, organic C, N and soil C:P and C:N ratios. The principal component analysis showed that the samples grouped according to the sites, with a clear gradient from campo graminóide to cerradão. Therefore, the differences of vegetation across physiognomies of Cerrado influenced the soil microbial C:N:P ratio, where cerradão showed highest microbial C:N:P ratio than soil under campo graminóide.

ABSTRACT The different physiognomies and soil conditions across the Cerrado gradient may influence soil microbial biomass. The present study evaluated the soil microbial biomass and enzyme activity across a preserved Cerrado gradient and correlated these with environmental conditions. The site, sampling period and their interaction influenced soil microbial biomass and activity. Soil conditions, i.e., chemical and microclimatic properties, varied across the Cerrado gradient and influenced soil microbial biomass and activity. The highest and lowest values for microbial biomass and enzyme activity were found in Cerradao and Campo graminoide, respectively, during both seasons. Multivariate analysis showed that the sites were clearly separated into different groups, indicating that distinct physiognomies and environmental conditions influenced soil microbial biomass and enzyme activities.

Abstract: Trophic interactions impose important costs to their host plants, affecting patterns of resource allocation. The relationship between host and consumers is also influenced by the availability of resources, e.g., soil nutrients. In this study, we explored the relationship among mycorrhiza-plantherbivore in natural populations of Datura stramonium and their correlation with the content of phosphorus, nitrogen and carbon in the soil. We estimated the vegetative and reproductive biomass of plants, the arbuscular mycorrhizal colonization and the level of herbivory in populations of D. stramonium. The local abundance of D. stramonium was negatively related to the content of phosphorus in the soil. In contrast, soil carbon concentration affected positively the vegetative and reproductive mass of D. stramonium, although it was negatively correlated with the specific leaf area (SLA). Of the trophic interactions only herbivory was significantly correlated with the SLA and no relationship was detected between the two interaction types. The lack of significant response of mycorrhizae to the soil nutrients concentration, plant performance, and herbivory may result from the stochasticity in the availability of mycorrhizal inoculum (identity and abundance) in the populations studied.

Resumen: Las interacciones tróficas representan importantes costos a las plantas afectando sus patrones de asignación de recursos. Además las relaciones entre hospederos y sus interactuantes son afectadas por la disponibilidad de recursos, por ejemplo, nutrientes del suelo. En este estudio, exploramos la relación entre las interacciones tróficas micorriza-planta-herbívoro en poblaciones naturales de Datura stramonium, y su correlación con la concentración de fósforo, nitrógeno y carbono en el suelo. Se estimó la masa vegetativa y reproductiva de las plantas, el nivel de colonización por micorrizas arbusculares en sus raíces, así como el nivel de herbivoría en ocho poblaciones de D. stramonium. La abundancia local de D. stramonium estuvo relacionada negativamente con el contenido de fósforo en el suelo. Por otra parte, la concentración de carbono afectó positivamente la masa vegetativa y reproductiva de las plantas, aunque tuvo un efecto negativo en el área foliar específica (AFE). De las interacciones tróficas, sólo la herbivoría estuvo relacionada significativamente con el AFE y no se detectó relación entre ambos tipos de interacción. La falta de respuesta significativa de las micorrizas a la concentración de nutrientes, al desempeño de las plantas y a la herbivoría puede ser consecuencia de la estocasticidad en la disponibilidad de inóculo micorrizógeno (identidad y abundancia) en las poblaciones estudiadas o bien con la época de muestreo de las plantas.

Resumo O Colágeno hidrolisado bovino (CHB) é um importante suplemento alimentar normalmente consumido na forma de cápsulas ou pós com o intuito de estimular a síntese de colágeno corpórea, promover a saúde e auxiliar na estética. A transformação de alimentos líquidos em pós através da secagem é uma operação difícil devido às complexas transformações físico-químicas decorrentes da elevada temperatura, o que pode resultar em baixa eficiência de secagem e características físico-químicas e nutricionais indesejadas no produto final. Neste trabalho, uma abordagem de engenharia de processos foi utilizada com o objetivo de maximizar a eficiência de secagem e investigar o potencial do secador de leito de jorro durante a etapa de secagem de CHB. Os efeitos do método de alimentação de pasta, tipo de inerte, bem como o uso de adjuvante foram analisados em relação à eficiência de obtenção de pó, a partir de um planejamento experimental fatorial 23. A análise estatística dos resultados revelou que todas as variáveis independentes apresentam efeito significativo sobre a eficiência de secagem. As máximas eficiências de produção de pó foram alcançadas com a utilização de polipropileno como material inerte e atomização como modo de alimentação. Nas condições ótimas de processo, foi obtida eficiência de até 85%, demonstrando que o leito de jorro é viável tecnicamente para secagem de CHB.

Summary Bovine hydrolyzed collagen (BHC) is an important food supplement normally consumed in the form of capsules or powder in order to stimulate the synthesis of collagen, promote health and assist in esthetics. The transformation of liquid foods into powders by drying is a difficult operation due to the complex physical and chemical changes resulting from the use of high temperatures, which may result in low drying efficiency and unwanted physicochemical and nutritional characteristics in the final product. In this work, a process engineering approach was used aiming to maximize the drying efficiency and investigate the potential of using a spouted bed on the drying performance of BHC. The effects of feed mode, type of inert material and use of an adjuvant on powder production efficiency were analyzed using a 23 factorial experimental design. A statistical analysis showed significant effects of all the independent variables on drying performance. The maximum powder production efficiencies were achieved using polypropylene as the inert material and atomization as the feed mode. Under the optimal process conditions, up to 85% efficiency was obtained, demonstrating that the spouted bed is a technically viable equipment for drying BHC.

Neste texto problematizamos a prática cultural do ato do próprio sujeito se narrar no contexto urbano, partindo de conceções sobre a linguagem, as tecnologias urbanas e as narrativas realizadas nas interações da vida quotidiana. Apresentamos uma análise das observações recolhidas numa investigação realizada na cidade de Santa Maria - RS - BR, envolvendo recolha e análise de imagens e conversas com condutores de veículos e leitores dos autocolantes de carros, popularmente conhecidos como ‘stickers da família feliz'. Entre outras conclusões, verificamos que os autocolantes da “família feliz”, colocados estrategicamente nos parachoques dos carros, instigam vários processos de significação elucidativos de formas individuais e coletivas de narrativa auto e hétero identitária, em contexto urbano.

Based on conceptions about language, urban technologies and narratives consummated within everyday life interactions, we problematize the cultural practice of narration in the urban context. We present the analysis of the data gathered during a research developed in the city of Santa Maria, Brazil, involving the collection and analysis of images and conversations with car drivers, as well as readers of car stickers, popularly known as “happy family” stickers. Among other findings, we observed that “happy family” stickers, strategically applied on the bumpers of cars, instigate several enlightening meaning processes of individual and collective forms of self and hetero identitarian narrative in the urban context.