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1.
São Paulo; s.n; s.n; 2023. 107 p. tab, graf, ilus.
Tesis en Portugués | LILACS | ID: biblio-1437843

RESUMEN

Atualmente a agricultura ocupa um papel de extrema importância na conjuntura global e nacional e está inserida em um contexto de enormes desafios devido ao aumento da população mundial e maior demanda por alimentos. Ao mesmo tempo, é o setor mais afetado pelos impactos negativos das mudanças climáticas, que têm espalhado suas consequências de maneira cada vez mais frequente e intensa. Um dos principais efeitos é a alteração do regime de chuvas ao redor do globo, ocasionando estiagens intensas e duradouras, capazes de reduzir a produtividade de safras e comprometer a produção alimentícia. As abordagens atualmente existentes no mercado para mitigar as consequências negativas da escassez hídrica demandam alto investimento de implementação e manutenção, ou possuem um perfil ecotoxicológico insatisfatório. Polímeros de origem natural modificados quimicamente foram avaliados em termos de desempenho e capacidade de prover às plantas uma maior disponibilidade de água através de retenção hídrica. Os resultados alcançados demonstraram que os polímeros modificados com grupos iônicos foram capazes de promover um melhor gerenciamento hídrico no microambiente ao redor de sementes e entregar ganhos de produtividade a lavouras de soja. O mecanismo de ação da tecnologia estudada foi elucidado através de ensaios de determinação de capacidade de campo, análise de elipsometria, microscopia de força atômica, ensaios de germinação de soja sob estresse hídrico e implementação de áreas de soja a céu aberto a partir da aplicação em tratamento de sementes e sulco de plantio. As interações intra e intermoleculares entre as partículas de solo, moléculas de polímero e de água se mostraram ponto chave para a mudança de patamar de desempenho de polímeros naturais modificados utilizados na agricultura, quando comparados com os grupos controle. A tecnologia aqui estudada é, portanto, recomendada para utilização na agricultura, com capacidade de potencializar o efeito de tecnologias dependentes de água, resultando em maior produtividade na colheita


Nowadays agriculture occupies an extremely important role both in the global and national scenarios. Its included in a very challenging context due to the forecast of increased world population and consequent higher demand for food. At the same time, it is the most affected economic sector by the climate change effects, which have been causing frequent and harsh impacts. One of the main effects is the change in the rainfall pattern worldwide, which causes severe and long-lasting droughts, responsible for causing crops to fail and therefore putting food production at risk. The current available mitigation measures to address hydric scarcity require a huge investment for implementation and maintenance or do not present a satisfactory and safe ecotoxicological profile. Chemically modified natural polymers have been evaluated in terms of performance and ability to provide the plants with higher water availability through hydric retention. The results obtained show that such ionic group modified polymers are able to promote better water management in a given microenvironment surrounding the seeds and ultimately delivery a higher yield to soy crops. The technology's mode of action has been elucidated through field capacity determination trials, ellipsometry, atomic force microscopy, soy germination trials under hydric stress and, finally, implementation of soy areas under actual field conditions by applying the polymers via seed treatment and in-furrow methods. Both intra- and intermolecular interaction between soil particles, polymer and water molecules have been proven as key to understanding the agricultural performance improvement of the modified polymers when compared to the control. The technology is recommended for agricultural applications due to its ability to boost the effect of water-dependent technologies, promoting higher yields


Asunto(s)
Polímeros/análisis , Deshidratación/complicaciones , Agricultura/clasificación , Polisacáridos/efectos adversos , Suelo , Glycine max/crecimiento & desarrollo , Agua , Eficiencia/clasificación , Alimentos/clasificación
2.
Braz. J. Pharm. Sci. (Online) ; 56: e18500, 2020. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1142493

RESUMEN

Ethephon (Ethrel®) is an ethylene-based plant growth regulator that used in agriculture and it has direct and indirect effects on human health, direct effect via its inhalation during usage in agriculture and indirect effect through the diet (Fruits and vegetables) that is sprayed with it. The current study aimed to examine the possible modifying effects of costus (Saussurea lappa) root aqueous extract against Ethephon induced liver toxicity, injury, DNA fragmentation and PCNA alterations in male rats. Fifty adult male rats were divided into 5 groups (1st, control; 2nd, Costus; 3rd, Ethephon; 4th, Post treated Ethephon with costus; 5th, self-healing Ethephon). Current results revealed that; a significant increase in aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), liver injury, DNA damage and PCNA expressions in Ethephon group when compared with control group. In contrast; a significant decrease in albumin and total proteins in Ethephon group when compared with control group. Treatment of rats with costus after Ethephon improved these alterations as compared with Ethephon self-healing. So, it could be concluded that costus root extract worth to be considered as a natural substance for ameliorating the hepatic toxicity induced by plant growth regulator Ethephon.


Asunto(s)
Animales , Masculino , Ratas , Reguladores del Crecimiento de las Plantas/agonistas , Extractos Vegetales/análisis , Costus/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas , Daño del ADN , Inhalación , Antígeno Nuclear de Célula en Proliferación , Agricultura/clasificación , Hígado/anomalías
3.
Braz. j. biol ; 75(2): 396-404, 05/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-749705

RESUMEN

The mite community has been surveyed in Seasonal Semideciduous Forest with three types of surrounding agricultural environments to test the hypothesis that abundance and richness of mites in forest fragments are influenced by the type of agricultural environment. The survey has been carried out in six fragments, divided into sets of two fragments, each one neighboring one sort of agricultural environment: sugarcane crop (FS), orange crop (FO) and pasture (FP). In each fragment, ten individuals of Actinostemon communis (Euphorbiaceae) were selected, five at the edge and five within each fragment. Iphiseiodes zuluagai, often registered in orange crops, was more abundant in the fragments neighboring such crop, as well as some species of Tarsonemidae. In this study, the Phytoseiidae were more abundant in the fragments neighboring pasture, while sugarcane crops probably favored occurrence of phytophagous mites in the neighboring fragments. Tetranychidae were less abundant in FO, which can be explained by periodical use of pesticides in the orange crops. Forest fragments are important for colonies of predators in the neighboring crops, mainly for annual crops such as sugarcane, where the close perennial environment is very important for colonization of the crop. Maintenance of those areas, besides favoring preservation of wild species of mite, is very important to increase diversity of the neighboring agricultural ecosystems.


Foi estudada a comunidade de ácaros em fragmentos de mata estacional semidecidual com três tipos de ambientes agrícolas circunvizinhos para testar a hipótese de que a abundância e a riqueza de ácaros em fragmentos florestais são influenciadas pelo tipo de ambiente agrícola. O estudo foi conduzido em seis fragmentos, divididos em três conjuntos de dois fragmentos, sendo cada conjunto vizinho de um determinado tipo de ambiente agrícola: canavial (FS), laranjal (FO) e pastagem (FP). Em cada fragmento foram selecionados e marcados dez indivíduos de Actinostemon communis (Euphorbiaceae), cinco na borda e cinco no interior do fragmento. Iphiseiodes zuluagai, registrado frequentemente em laranjais, foi mais abundante nos fragmentos vizinhos a essa cultura, bem como algumas espécies de Tarsonemidae. Neste estudo os fitoseídeos foram mais abundantes nos fragmentos vizinhos de áreas de pastagens, enquanto os cultivos de cana-de-açúcar provavelmente favoreceram a ocorrência de fitófagos nos fragmentos adjacentes. Os tetraniquídeos foram menos abundantes em FO, o que pode ser explicado pela aplicação periódica de pesticidas nos laranjais. Fragmentos florestais são importantes para a colonização de predadores nas culturas vizinhas, principalmente em culturas anuais, como a cana-de-açúcar, nas quais o ambiente perene próximo é muito importante para a colonização do cultivo. A conservação dessas áreas, além de favorecer a manutenção de espécies silvestres de ácaros é de grande importância para o aumento da diversidade nos agroecossistemas vizinhos.


Asunto(s)
Animales , Agricultura/clasificación , Biodiversidad , Bosques , Ácaros , Densidad de Población , Dinámica Poblacional
4.
Agora USB ; 11(2): 403-422, jul.-dec. 2011.
Artículo en Español | LILACS | ID: lil-678739

RESUMEN

La realidad económica de nuestro país se ha orientado a encontrar nuevas formas de solucionar viejos problemas que atañen al sector primario, la acuicultura desarrollada desde las culturas primitivas de México ha crecido paulatinamente, mas como un esfuerzo constante por participar en actividades productivas de autoconsumo que con la intención de enfocar a las pequeñas empresas a formar proyectos conjuntos de articulación productiva y de desarrollo de Innovación. Este artículo de investigación, plantea tres aspectos esenciales: 1) las condiciones de las empresas rurales granjas acuícolas de la región occidente de México, en los estados de Colima, Jalisco, Michoacán y Nayarit, 2) Las modalidades de articulación productiva, redes o agrupamientos de organizaciones alrededor de las granjas acuícolas 3) Las características de los procesos de las granjas y su orientación a la innovación; la investigación analiza la manera en que las empresas, gobierno y la sociedad en su conjunto participan a través del trabajo común para la formalización de proyectos económicos que modifiquen a largo plazo las condiciones sociales de la población.


The economic reality of our country has been oriented to find new ways to solve old problems pertaining to the primary sector, aquaculture developed from the very primitive cultures in Mexico has grown gradually, more like a constant effort to participate in productive activities for self-consumption than intending to focus on small firms to form joint projects of productive articulation and development of innovation. This research article, poses Three essential aspects: 1) the conditions of rural enterprises aquaculture farms in the western region of Mexico, in the States of Colima, Jalisco, Michoacan and Nayarit, 2) modalities of productive articulation, networks or groupings of organizations around aquaculture farms 3) the characteristics of the processes on the farms and their orientation to innovation; this research analyzes the way in which businesses, the government and society, as a whole, participate through common work for the formalization of economic projects which modify, in the long run, the population’s social conditions.


Asunto(s)
Humanos , Agricultura , Agua Dulce/análisis , Agricultura/clasificación , Agricultura/economía , Agricultura/educación , Agricultura/historia , Agricultura/legislación & jurisprudencia , Agricultura/organización & administración , Agricultura
5.
Journal of Karbala University. 2005; 2 (9): 10-21
en Arabe | IMEMR | ID: emr-71945

RESUMEN

This research represents and attempt to evaluate the ability of using Cosmos satellite image for land-use classification in one of the most populated region in Baghdad [Al-Sheikh'Omar], which characterized by irregular land-use and different environments. Such variety can be recognized by wide range of image brightness values and interfering between classes [asphalt, metal roofed galleries ' etc]. this small area represent different types of land-use [industrial, commercial, governmental, and housing], and that point to exist of different subclasses in the main classes. Erdas program used to treat Cosmos image cover the pointed region, which include digital processing and analysis firstly, and digital classification secondly. The first process includes making radiometrical enhancement [contrast and density slicing], so as to separate high buildings fro metal roofed galleries, in addition to spatial enhancement [edge enhancement and spatial filtering] to get out back street of [1.8] m wide or more further to main street. While digital classification includes applicating of three types of classification [supervised, unsupervised, and hybrid]. The study concludes that the hybrid classification has a good ability to avoid the difficulty of training all land-use categories in one hand, and to treat the interference between them on the other. So hybrid classification is important to separate street from houses, buildings and metal roofed galleries, and consider as the best between others. While the unsupervised classification was more simple, clear and object, that make use of it in determining the identifying regions for the supervised classification which in turn very useful and accurate in getting out houses


Asunto(s)
Comunicaciones por Satélite , Agricultura/clasificación , Población Urbana/clasificación
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