Amelioration of Drought Stress on Plants under Biostimulant Sources

Water stress is one of the most important environmental factors inducing physiological changes in plants, such as decreasing water potential of the cells and the stomatal closure, resulting in reduced CO2 availability for the plants and inhibiting photosynthesis. One common feature of these stress conditions is the development of oxidative processes mediated by reactive oxygen species (ROS). ROS accumulate in the cells and cause damage in important cellular components, such as thylakoids and chloroplasts. Plants have antioxidant defense systems to cope with ROS. Antioxidants enzymes superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) are efficient scavengers of ROS: superoxide, hydroxyl radicals, and singlet oxygen. The activities of antioxidant enzymes in plants are normally favored when plants are subjected to some kind of improvement in the conditions in which they are grown. In this sense, biostimulants cause changes in vital and structural processes in order to influence plant growth through improved tolerance to abiotic stresses by increasing the antioxidant activity in plants

Biochar Effects on Amelioration of Adverse Salinity Effects in Soils

Biochar is the term given to biomass subjected to the process of change in the composition by the action of high temperatures. Advantages of biochar in soil quality have been reported, including amelioration of salinity effects. Salinity has a negative effect on soil physical properties and plant production by adversely affecting the process of plant growth, hence seed germination, nutrient uptake, and yield. Moreover, salt stress causes oxidative stress in plant and the reduction in antioxidant enzyme activities. Biochar is an amendment, which could decrease the negative effect of salt stress on crop growth and production. Application of biochar enriches mineral nutrients; improves the soil’s physical, chemical, and biological characteristics such as bulk density, hydrological properties, aggregate structure, ion exchange capacity, and microbial activity; and consequently enhances plant growth. Enhancing physical properties, biochar balances water holding capacity and air porosity in soils. Biochar promotes benefits in plant growth in saline soils through reduction in oxidation stress and in osmotic stress, lower production of phytohormones, improvement in stomatal density and conductance, improvement in seed germination, and the promotion of microbial activities. Biochar amendment can contribute to reduce salt stress in plants under saline condition due to its high salt adsorption capability

Biostimulants and Their Role in Improving Plant Growth under Abiotic Stresses

Biostimulants are products that reduce the need for fertilizers and increase plant growth, resistance to water and abiotic stresses. In small concentrations, these substances are efficient, favoring the good performance of the plant’s vital processes, and allowing high yields and good quality products. In addition, biostimulants applied to plants enhance nutrition efficiency, abiotic stress tolerance and/or plant quality traits, regardless of its nutrient contents. Several researches have been developed in order to evaluate the biostimulants in improving plant development subjected to stresses, saline environment, and development of seedlings, among others. Furthermore, various raw materials have been used in biostimulant compositions, such as humic acids, hormones, algae extracts, and plant growth-promoting bacteria. In this sense, this chapter aims to approach the use of biostimulants in plant growth according to the raw material used in their compositions as well as their effects on plants subjected to abiotic stresses

Respostas de enzimas antioxidantes a bioestimulantes em plantas de milho e de soja sob estresse hídrico

Water stress is one of the most important environmental factors inducing physiological changes in plants, such as decrease in the water potential of the cells, the stomatal closure; and the development of oxidative processes mediated by reactive oxygen species (ROS). Antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) are efficient scavengers of ROS. The aim of this research was to examine how the application of biostimulant based on humic substances and aminoacids may affect activity levels of SOD, CAT, and APX of maize and soybean plants under well-watered or drought stress conditions. Pots (4.5 L) were filled with a Typic Hapludult soil where the biostimulants doses were applied. It was taken leaf samples in order to analyze SOD, CAT, and APX activities in plants. SOD and APX activity levels were increased by application of biostimulant 1 in maize subjected to stress. Catalase activity was not enhanced in plants by using the biostimulants. The composition of the biostimulants was not able to enhance stress tolerance in maize and soybean plants subjected to water stress.O estresse hídrico é um dos mais importantes fatores ambientais que induz mudanças fisiológicas, como diminuição do potencial de água na célula, o fechamento dos estômatos e o desenvolvimento de processos oxidativos mediante a formação das espécies reativas de oxigênio (ROS). As enzimas antioxidantes superóxido dismutase (SOD), catalase (CAT) e ascorbato peroxidase (APX) são eficientes eliminadores das ROS. O objetivo deste estudo foi examinar como a aplicação de bioestimulantes com substâncias húmicas e aminoácidos em sua composição afeta os níveis de SOD, CAT e APX nos tecidos das folhas de plantas de milho e de soja cultivadas com ou sem estresse hídrico. Amostras de um Argissolo foram colocadas em vasos (4,5 L) onde foram adicionadas as doses dos bioestimulantes. Foram retiradas amostras de folhas para análise da atividade da SOD, CAT e APX nas plantas. A SOD e APX aumentaram nas plantas de milho com a aplicação do bioestimulante 1. A atividade da CAT não aumentou nas plantas com a aplicação dos bioestimulantes. As composições dos bioestimulantes não possibilitaram aumento na resistência ao estresse hídrico em plantas de milho e de soja submetidas ao estresse hídricoCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Satellite images on the discrimination of soils developed from basalt and sandstone of Paraguaçu Paulista region

O objetivo deste trabalho foi avaliar o potencial de discriminação de solos, mediante informações espectrais obtidas por sensor remoto em satélite. Os solos apresentaram variações na forma da curva espectral e intensidades de reflectância. Os Nitossolos apresentaram baixa intensidade de reflectância e os Neossolos, bastante alta. Os Latossolos Vermelhos, com diferentes texturas, apresentaram aumento na intensidade de reflectância, na seqüência dos mais argilosos para os mais arenosos. Solos eutróficos apresentaram maiores intensidades de reflectância que os álicos. A análise discriminante indicou um erro geral de 0,028%. As amostras confundidas geralmente ocorreram entre os solos com características semelhantes. A metodologia empregada na coleta de dados espectrais de satélites mostrou-se eficiente, tornando possível discriminar os solos da região estudada e, assim, agilizar a confecção de mapas de solos.The objective of this work was to evaluate soil characterization and discrimination by spectral information obtained from satellite sensor. Soils presented variation on the spectral signature, and on their spectral intensity. Typic Argiudoll (Alfisols) presented low spectral intensity, and Typic Quartzpisament presented a high spectral intensity. Typic Haplorthox (Oxisols) presented increments in its reflectance according to the texture. Eutrophic soils presented greater reflectance intensities than Alic soils. The discriminate analyses indicate a 0.028% error. Mistake samples occurred due to similar characteristics of soils. The methodology used to collect spectral data from satellite sensor showed to be efficient, and made possible soil discrimination, as well as faster soil survey of the presented region

Desenvolvimento e aceitabilidade de biscoito tipo cookie, sem glúten e à base de feijão caupi branco

Gluten is an elastic substance, adherent, water-insoluble and responsible for the structure of different kinds of pasta, being composed of fractions of proteins, glutenin and gliadin. The celiac disease is an autoimmune disease that affects the small intestine directly interfering with the absorption of essential nutrients such as carbohydrates, fats, proteins, vitamins, minerals and water. The aim of this study was to develop and sensory evaluate cookies, gluten free, white cowpea beans based, with regional and accessible ingredients. The evaluation took place by an affective test using a structured five points ideal scale referring to the attributes color, appearance, aroma, texture and flavors as cinnamon, nutmeg and beans. Furthermore, it was also carried an purchase intention test of the product. Global characteristics, such as appearance (78.4%) and color (78.4%) were those with the highest acceptance rate, followed by flavor (76.5%) and texture (68.6%). Among the percentage of identification of flavors just “bean flavor” (80.4%) had satisfactory rate, being rated as absent or weak which was a desired characteristic for this product. According to the percentage of 49% of purchase intention, the developed cookie has potential for commercialization and could become another option for people with celiac disease. Keywords: gluten-free diet, celiac disease, food technology.O glúten é uma substância elástica, aderente, insolúvel em água e responsável pela estrutura das massas alimentícias, sendo constituído por frações das proteínas gliadina e glutenina. A doença celíaca é uma doença autoimune, que afeta o intestino delgado, interferindo diretamente na absorção de nutrientes essenciais ao organismo, como carboidratos, gorduras, proteínas, vitaminas, sais minerais e água. Este trabalho teve como objetivo desenvolver e avaliar sensorialmente um biscoito tipo cookie, sem glúten, à base de feijão caupi branco, formulado a partir de ingredientes regionais de fácil acesso. A avaliação sensorial do biscoito se deu por teste afetivo com escala ideal estruturada em cinco pontos referentes aos atributos de cor, aparência, aroma, textura e sabores de canela, noz moscada e feijão. Além disso, também foi realizado teste de intenção de compra do produto. As características globais do produto, como a aparência (78,4%) e a cor (78,4%), foram as que apresentaram os maiores índices de aceitação, seguidos por aroma (76,5%) e textura (68,6%). Dentre o percentual de identificação dos sabores, apenas o “sabor de feijão” (80,4%) apresentou índice satisfatório, sendo avaliado como ausente ou de fraca característica desejada para o produto. Frente ao percentual de 49% de intenção de compra, o cookie desenvolvido apresenta potencial para comercialização, podendo vir a ser mais uma opção para pessoas com doença celíaca

Mudanças climáticas e percepções de atores sociais no meio rural*

As percepções humanas sobre mudanças climáticas podem influenciar fortemente a construção e a condução de estratégias de adaptação. Este trabalho discute aspectos teóricos de fatores sócio-culturais relacionados aos impactos das mudanças climáticas, e um estudo de caso conduzido em Anchieta, Santa Catarina, sobre percepções dessas mudanças segundo diferentes atores do meio rural

A relevância dos dados epidemiológicos das zoonoses e sua aplicabilidade na saúde única / The relevance of zoonoses epidemiological data and their unique health applicability

O termo epidemiologia vem de origem grega e tem como significado “estudo da população” pois esta estuda o processo de saúde e doença na população, tendo o objetivo de analisar os fatores desencadeantes e trazer medidas de prevenção, controle ou até mesmo a erradicação das mesmas. A epidemiologia é uma das áreas fundamentais na elaboração das estratégias públicas de combate e prevenção às patologias que acometem a sociedade. Ultimamente temos visto o aumento da ocorrência de zoonoses por conta da crescente mudança no ecossistema e estilo de vida, como a urbanização, turismo e desmatamento. Os benefícios dos dados epidemiológicos que são mensurados e descritos traz a possibilidades de controle e prevenção de surtos e epidemias. Neste trabalho objetivou-se demonstrar a importância da epidemiologia das zoonoses no conceito de saúde única

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio