Influência do herbicida Glifosato (N-Fosfonometil)Glicina) na formação de biomassa da alga Pseudokirchneriella subcapitata (Chlorophyceae)

Herbicides are chemical agents most consumed for agricultural production and of these, glyphosate (N-(phosphonomethyl) glycine) represents more than half of world consumption of non-selective herbicides, use of systemic action and post-emergent. The present study aims to analyze the interference of different concentrations of glyphosate in the development of micro algae, unicellular species Pseudokirchneriella subcapitata, with supplementary analysis of the interference of green algae concentrations in the artificial lake Instituto de Biociências Universidade Estadual Paulista in Rio Claro, SP. To identify the effect of glyphosate on the development of microalgae concentrations: 0.118; 0.236; 0.472; 0.944; 1.888 and 3.776 mg of product (all in rejoinders), maintaining control without glyphosate, were inoculated into flasks containing 150mL of medium culture and 5mL of suspension inoculum levels. Each test was continued for 96 hours in a shaker rotating at 150 rpm at 25 / - 2 ° C and constant light of 3200 lux. At baseline and 48; 72 and 96 hours samples were taken for testing for absorbance. The final dry weight was measured and the tests with P. subcapitata cell number was quantified at the beginning and end of the tests using the Neubauer chamber under optical microscope. For algae of the artificial lake of the diversity of microalgae cells was identified through photographic documentation. The analysis of variance comparing treatments for dry biomass showed no significant differences in the tests with P. subicapitata as for the algae to the lake.The analysis of variance MANOVA showed significant differences between the treatments over time but there was no significant difference between the interactions of treatment for tests with P. subicapitata There were significant differences in the tests with microalgae of the artificial lake. With respect to cell quantification, it was found... (Complete abstract click electronic acces below)

Determinantes da expansão da soja transgênica no Brasil

O presente trabalho procura descrever o histórico e a trajetória percorrida pela soja em sua expansão pelo território nacional, considerando a utilização da soja transgênica. Explica quais diferenças e melhorias a soja transgênica apresenta em comparação a soja convencional, discutindo-se a liberalização ou não do uso e consumo de produtos derivados de transgênicos. Expõem ainda, quais foram os fatores preponderantes para a escolha do uso dessa técnica: a rede de persuasão e controle criada e coordenada pela Monsanto e a redução do custo de produção, através da diminuição do uso de herbicidas

Expressão do gene Glipican 3 (Gpc3) no urotélio da bexiga de ratos expostos ao diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) por 7 dias e 20 semanas

Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a substituted urea herbicide widely used in crops of sugar cane, cotton and soybeans. In 1997, this agent has been classified by the United States Environmental Protection Agency as known/likely human carcinogen because it induced tumors in the urinary bladder and renal pelvis of rats, and breast and skin of mice exposed to 2500 ppm for feed for two years. A previous study from our group demonstrated dose-response relationship in the gene expression profile associated with severe necrosis on bladder urothelium and increased incidence of simple hyperplasia in male Wistar rats treated with different concentrations of diuron for 20 weeks. To check how early the molecular changes occurs, rats were fed for 7 days with diets containing diuron at 0, 125, 500 or 2500 ppm. The main observations recorded were urothelium ultrastructural alterations and disruptions of molecular pathways associated with cell-cell interaction and the tissue organization maintenance. Particularly, the gene Glypican 3 (Gpc3), a surface proteoglycan related to cellular adhesion and apoptosis induction, was down regulated on urothelium exposed to 2500ppm diuron for 7 days and 20 weeks. The aim of this study was validate by quantitative RT-PCR real time, the reduced Gpc3 gene expression in epithelial cells of the urinary bladder of male Wistar rats treated with different concentrations of diuron for 7 days and 20 weeks. The endogenous control of the quantitative PCR real time technique was the β-actin gene and the target was the gene Gpc3. The relative quantification (RQ) was obtained by the method of relative quantification 2-ΔΔCt . Animals exposed to diuron for 7 days or for 20 weeks presented reduction of Gpc3 gene expression compared to the control group. This reduction was statistically significant only for the 7 days study. Moreover, by comparing animals exposed for 7 days with the exposed for 20 weeks, it was ...

Alterações comportamentais em Geophagus brasiliensis submetidos a ação do herbicida glifosato

Os herbicidas a base de glifosato, como a formulação comercial Roundup®, tem sido amplamente utilizado para o controle de ervas daninhas na agricultura brasileira. O uso desses herbicidas podem resultar no rompimento do equilíbrio ecológico, podendo causar danos a organismos não- alvo, como os peixes. Para testar se o glifosato altera comportamento de peixes, utilizamos o Geophagus brasiliensis, nativo de várias regiões do Brasil, espécie territorialista e que se utiliza de confrontos agonísticos para estabelecer hierarquia de dominância. Neste estudo, encontramos o valor da concentração letal capaz de promover a morte de 50% da população em 96 horas (CL₅₀,₉₆h= 1,8 mgL⁻1). No entanto, nos testes de interações agonísticas foi utilizado uma dosagem subletal de 0,72 mgL⁻1, afim de avaliar possíveis alterações na agressividade de Geophagus brasiliensis. Testamos o efeito de glifosato em um grupo experimental, e um grupo controle com peixes que não foram expostos ao herbicida glifosato. Um etograma foi elaborado para quantificar as interações agonísticas. Ao comparar os dois tratamentos, foi possível observar um aumento no número de interações agonísticas no grupo exposto ao glifosato em relação ao grupo controle. No pareamento entre peixes tratados versus peixes não tratados, a média de interações foi maior para o peixe não tratado (controle) e a latência para os confrontos desse grupo foi menor, indicando que a exposição ao herbicida Roundup®promove, possivelmente, alterações físicas e/ou químicas nos animais e esses sinalizam de alguma forma para o seu oponente

Análise morfológica de brânquias de peixes Oreochromis niloticus (tilápia) expostos ao níquel

Water is an essential factor in maintaining the vital functions of living beings. We have observed a growing commitment of quality, are due to pollution from many sources and even entire watersheds, whether for industrial waste, sewage, or for substances used in farming such as pesticides, herbicides and fertilizers. Nickel is the 24th most abundant element on earth, is a heavy metal that, in the form of chloride, is a proven genotoxic and mutagenic. Due to its industrial use, there was considerable increase of its concentration in surface sediments. Fish combine characteristics that make them excellent experimental models for aquatic toxicology studies, which are particularly usable as warn about the potential danger of chemicals or the possibility of environmental pollution. Due to impaired water quality and the few published studies relating the nickel with the tissue change, this study aimed at assessing the consequences of the presence of nickel in the aquatic environment. For this analysis, we used individuals of Oreochromis niloticus, exposed for 96 hours at three different concentrations of nickel dissolved in water compared to a control group. After exposure, the gills were removed and these were analyzed by ultramorphological, histological and histochemical analysis. The results indicate that all concentrations used in the experiment altered the histophysiology of exposed individuals. We observed the following changes: rupture of paviment cells, thus resulting in bleeding, loss of microridges surface of these cells and epithelial loss in the gills of all animals in all treatments with nickel chloride, the histochemical analysis showed non-proliferation of chloride cells. However, there was a dose-dependent increase of mucus cells in all animals. Therefore, nickel has toxic potential to fish, from the smallest concentration used up to twice as permitted by law, indicating... (Complete abstract click electronic access below)

Avaliação do efeito tóxico do herbicida trifluralina por meio do estudo histológico e histoquímico do intestino médio do diplópodo Rhinocricus padbergi

Currently the use of pesticides in agriculture is widespread due to their high effectiveness in combating pests, weeds and diseases leading to better productivity and economical performance in agricultural area. The use of pesticides affects the whole world and their use is often performed in an improper and indiscriminate way and for long periods. Several studies have been carried out in order to verify the presence of pesticides in nature, with worrying results. The presence of higher levels of pesticides and their degradation products in soil and surface and groundwater have indicated increasing contamination. Among the most widely used pesticides, herbicides are present and among these trifluralin has occupied an important place due to its widespread use; it is an herbicide originated from benzene derivatives belonging to dinitroanilines family; it is classified as belonging to group C, being possibly carcinogenic for humans, present a high persistence in soil as a result of its low mobility and therefore may affect local edaphic fauna. Diplopods belong to a group of invertebrates considered important in the soil dynamics; due to their close contact with it, these animals can be used as bioindicators of substrates toxicity. This study aimed to expose diplopod specimens of the species R. padbergi to different concentrations of trifluralin and therefore it was mounted five bioassays containing soil from the site where animals were collected (control group) and the same soil mixed to different concentrations of trifluralin herbicide (concentration recommended for agriculture use, that is, the dose recommended by the producer 0.0534g/m2, double, haft and quarter of this dose), animals were exposed for 7 and 90 days. During the entire period of exposure (90 days), it was observed that the number of animals in the control bioassay remained stable until the 5th week, presenting only... (Complete abstract click electronic access below)

Períodos de interferência de Mucuna aterrima (Piper & Tracy) em cana-de-açúcar e seu controle químico

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Estudo sobre desruptores endócrinos em sistemas aquáticos: detecção e perspectivas de tratamento das águas do Rio Aporé-MS/GO, utilizando-se adsorventes sólidos

Pós-graduação em Ciência dos Materiais - FEIS

Hormesis de glyphosate em cana-de-açúcar

Pós-graduação em Agronomia (Agricultura) - FCA

Investigação da toxicidade, citotoxicidade e genotoxicidade de uma formulação comercial de 2,4-D (Diclorofenoxiacético) utilizando os organismos testes Allium cepa e Tradescantia pallida

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Suscetibilidade diferenciada de Synedrellopsis grisebachii ao herbicida glyphosate: efeito do sombreamento e do estágio de desenvolvimento

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Estudo do potencial de degradação do herbicida diuron e seus metabólitos por bactérias isoladas de solo de canavial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Degradação do herbicida diuron por bactérias isoladas de solos de cultura de cana-de-açúcar e avaliação da toxidade dos metabolitos gerados sobre peixes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biomarcadores de exposição e efeito para avaliação dos efeitos da atrazina a distintos níveis em girinos de anuros neotropicais

Pós-graduação em Biologia Animal - IBILCE

Avaliação do potencial de degradação do herbicida diuron por fungos isolados de solo de canavial e suas tolerâncias aos metabólitos gerados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)