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Manejo de soja transgênica com glifosato e imazetapir: efeito sobre a mesofauna e microbiota do solo  [cached]
Giani Mariza Barwald Bohm,Danilo Dufech Castilhos,Cesar Valmor Rombaldi
Revista Thema , 2010,
Abstract: A estabilidade de diferentes organismos da mesofauna, como ácaros e colêmbolos, e a atividade microbiana do solo s o indicadores de qualidade físico-química e biológica do solo. Este trabalho teve por objetivo avaliar o efeito de métodos de controle de plantas concorrentes sobre a qualidade do solo cultivado com soja transgênica. Neste contexto, foram cultivados dois genótipos de soja, geneticamente modificada (GMRR) BRS 244 RR e n o modificada (NM) BRS 154, no Centro Agropecuário da Palma da Universidade Federal de Pelotas (CAP), nas safras de 2005/2006 e 2006/2007. Para o controle de plantas daninhas, testaram-se, tratamentos com glifosato, imazetapir e capina. Avaliaram-se popula es de ácaros e colêmbolos, o carbono da biomassa microbiana, a respira o basal e o quociente metabólico do solo. Verificou-se que a aplica o dos herbicidas, principalmente de glifosato, em soja BRS 244 RR cultivada em Planossolo resultou em desestabilidade da mesofauna e maior atividade da biomassa microbiana.
Weed control, biomass and microbial metabolism of soil depending on the application of glyphosate and imazethapyr on crop soybeans Controle de plantas daninhas, biomassa e metabolismo microbiano do solo em fun o da aplica o de glifosato ou imazetapir na cultura da soja  [cached]
Giani Mariza Barwald Bohm,Léa Scheneider,Danilo Castilhos,Dirceu Agostinetto
Semina : Ciências Agrárias , 2011,
Abstract: Studied the weed control and the changes of biomass and microbial soil properties at crop cultivated both genetically modified and non altered soybeans because of glyphosate or imazethapyr herbicide applications. Soybean cultivations were tested (BRS 244RR), genetically modified and BRS 154, non modified) and herbicides (glyphosate and imazethapyr), and control treatment with weed. Variables were evaluated for phytotoxicity to the crop, control of Raphanus raphanistrum (wild radish), Digitaria sp. (crabgrass) and Brachiaria plantaginea (alexsandregrass), total organic carbon (TOC), microbial biomass carbon (MBC), basal respiration (BR) and metabolic quocient (QCO2). The herbicide glyphosate, applied as a single dose or sequentially, effectively controls the weeds wild radish, crabgrass and alexsandregrass and increases microbial activity, basal respiration and metabolic quocient. The microbial metabolism was not affected by the fact that the genotype or not genetically modified, but the use of the herbicide glyphosate. Estudou-se o controle de plantas daninhas, as varia es da biomassa e do metabolismo microbiano do solo em áreas cultivadas com soja geneticamente modificada e n o modificada, em fun o da aplica o dos herbicidas glifosato ou imazetapir. Testaram-se cultivares de soja (BRS 244RR, geneticamente modificada e BRS 154, n o modificada) e herbicidas (glifosato e imazetapir), e tratamento controle com capina. Como variáveis foram avaliadas a fitotoxicidade à cultura, controle de Raphanus raphanistrum (nabo), Digitaria sp. (milh ) e Brachiaria plantaginea (papu ), teores de carbono organico total (COT), carbono da biomassa microbiana (CBM), respira o basal (RB) e quociente metabólico (QCO2). O herbicida glifosato, aplicado em dose única ou seqüencial, controla eficientemente as plantas daninhas nabo, milh e papu , e aumenta a atividade microbiana, a taxa de respira o basal e o quociente metabólico. O metabolismo microbiano do solo n o foi afetado pelo genótipo, geneticamente modificado ou n o, mas sim pelo uso do herbicida glifosato.
Transforma??o genética e aplica??o de glifosato na microbiota do solo, fixa??o biológica de nitrogênio, qualidade e seguran?a de gr?os de soja geneticamente modificada
B?hm, Giani Mariza B?rwald;Rombaldi, Cesar Valmor;
Ciência Rural , 2010, DOI: 10.1590/S0103-84782010000100037
Abstract: the genetically modified soybean resistant to glyphosate (gmrr) is the main product of plant biotechnology, considering the evolution of the area cultivated and the use of this grain. eua, argentina and brazil are the largest producers of gmrr. the release of gmrr soybean cultivation in brazil was done based on researches that were accomplished in other countries without the validation of the same edaphoclimatic conditions. in this context, the main researches about environmental impact, plant metabolism, quality and safety of gmrr soybean with or without glyphosate application were collected and investigated. in general, the researches investigated showed some similar characteristics: a) few variables were studied; b) simulations in green house or in vitro are used to infer possible response on the field. although scarce, the researches denoted that the genetic transformation did not affect soil microorganisms, biological nitrogen fixation and composition of grains. the factor which could affect these variables is the glyphosate application in weed control, thus the risk of damage to the environment and the safety of products derived from this raw materialare due to the use of the herbicide during cultivation, and not to the genetic transformation. key words: transgenic soybean, soil microorganisms, herbicides residue, isoflavones.
Detec??o de sementes de soja geneticamente modificada tolerante ao herbicida glifosato
Funguetto, Claudete Izabel;Tillmann, Maria ?ngela André;Villela, Francisco Amaral;Dode, Luciana Bicca;
Revista Brasileira de Sementes , 2004, DOI: 10.1590/S0101-31222004000100020
Abstract: the objective of this study was to adjust methodology to detect soybean seeds tolerant to glyphosate, to characterize the symptoms, to establish the necessary minimum time capable to allow safe and possible evaluation of being reproduced. three independent assays were done, based on the germination test. in study 1, seeds were pre-imbibed in a substrate containing herbicide solution for 16 hours. in study 2 the substratum was imbibed with the herbicide. in the study 3, seeds were immersed in solution of the herbicide. the standard germination test, speed of germination, length of seedling root and shoot and percentage of seedling secondary roots were used as evaluation parameters. evaluations were made in the fourth day, until the final count, on the eighth day. all three methods allowed detection of soybean seeds tolerant to the herbicide glyphosate, in the period of five days. the most recommended methodlogies for routine use in seed analysis laboratory were sowing in substratum moistened with solution of the herbicide, at the concentration of 0,03% (480 g/l active ingredient) and pre-imbibing of the seeds for 16 hours, with solution containing 0,4% and 0,6% of glyphosate (480 g/l active ingredient) because they allow germination and the normal development of the aerial parts and root system of genetically modified seedlings. the following symptoms were observed in non gm seedlings : thickened points, longitudinal grooves and with yellowing of the hypocotyl, inhibition of the development of the primary root and of the emission of secondary roots, and the hypocotyl was proportionally larger than the primary root.
Bioensaios na detec??o e quantifica??o de sementes de soja geneticamente modificada resistente ao glifosato
Miranda, Denise Meza de;Tillmann, Maria ?ngela André;Balerini, Fábio;Villela, Francisco Amaral;
Revista Brasileira de Sementes , 2005, DOI: 10.1590/S0101-31222005000100012
Abstract: the world cultivation of genetically modified (gm) soybean resistant to glyphosate is increasing and the presence of these seeds in lots of conventional seeds has became a problem for international soybean trade. recognizing the importance of the new markets and gm products, seed technology will have to assure the genetic purity of the biotechnologically derived products through reliable, practical and low cost tests. in this context, the aims of this study were to verify the efficiency of the germination test with herbicide in the substratum (bioassays) in the detection and quantification of gm soybean seed mixtures in conventional seed samples. samples of conventional seeds were prepared with 0, 1, 3 and 5% gm soybean seeds and submitted to the procedures of pre-soak, soak and immersion in herbicide, installed in plastic trays containing 25 seeds, with and without association to the gmo detection kit. in the sequence, contaminated samples with 0, 1, 3, 5 and 8% gm soybean seeds were installed in paper rolls (25 and 50 seeds/roll) and plastic trays with 25 seeds following the pre-soak procedure in herbicide. six days after the installation, hypocotyl length, root length, number of secondary roots and the largest secondary root length were evaluated. the pre-soak procedure is the appropriate for the detection and quantification of gm soybean seed presence, permitting 100% successes in the detection, regardless of the contaminant percentage in conventional samples of soybean seeds and it presents accuracy in the quantification of gm soybean seed presence of up to 3% in conventional samples, and its precision is conditioned to the percentual of present mixture in the sample.
Compara??o de métodos na detec??o de sementes de soja geneticamente modificada resistente ao glifosato
Cunha, Cristina dos Santos Madruga;Tillmann, Maria ?ngela André;Villela, Francisco Amaral;Dode, Luciana Bicca;Balerini, Fabio;
Revista Brasileira de Sementes , 2005, DOI: 10.1590/S0101-31222005000100021
Abstract: due to the great importance of the trade business, there are significant world efforts in establishing gmo detection methods. currently, bioassays that analyse seedling phenotype, the elisa test and kits that enable specific transgene protein identification, and pcr to detect specific dna sequences are frequently used. the aim of this study was to compare the efficiency of different methods to detect rr soybean. genetically modified seed samples, tolerant to glyphosate and susceptible parental seeds were submitted to bioassays (pre-imbibed, imbibed and immersion in herbicide solutions and seedling spraying), the kit trait test and pcr detection. bioassays were shown to be more efficient, comparing the ratio cost/benefit. the seedling visual analysis is a very important parameter to be considered in gm soybean seeds detection.
Detec??o de soja geneticamente modificada tolerante ao glifosato por métodos baseados na atividade de enzimas
Menezes, Sabrina Mecca de;Tillmann, Maria ?ngela Andre;Dode, Luciana Bicca;Villela, Francisco Amaral;
Revista Brasileira de Sementes , 2004, DOI: 10.1590/S0101-31222004000200021
Abstract: progress in genetic engineering allow the production of genetically modified plants tolerant to the use of certain herbicides. the use of seeds of genetically modified plants is increasing quickly, and fast, practical and low cost detection methods need to be developed. the objective of this research was to establish a method for detection of soybean tolerant to glyphosate. two soy cultivars were compared, one tolerant to glyphosate and its genetically unmodified parent. the seeds were submitted to treatments of pre-imbibition for 16 hours, in water and herbicide solution containing 0,6% of the active ingredient at the temperature of 25°c for seven days. afterwards, the extraction and the determination of the activity of the enzyme peroxidase were carried out through the evaluation of the eletroforesis and of color reaction. the obtained results allowed the conclusion that it is possible to differentiate soy tolerance to herbicide glyphosate through color reaction. differences were observed in the enzyme peroxidase activity tolerant and susceptible to glyphosate cultivars.
Sistema hidrop?nico com uso de solu??o de herbicida na detec??o de soja geneticamente modificada resistente ao glifosato
Bertagnolli, Carla Medianeira;Tillmann, Maria ?ngela André;Villela, Francisco Amaral;
Revista Brasileira de Sementes , 2006, DOI: 10.1590/S0101-31222006000200024
Abstract: the objectives of this work were to verify the efficiency of the hydroponic system in the detection of genetically modified (gm) soybean seeds and to establish a detection protocol in the hydroponic system. seed samples of the two genotype were used, one genetically modified and the respective non-genetically modified (non-gm) parent. five assays were performed to establish the detection protocol, in assays i and ii the seed pre-germination was performed and later the seedlings were placed in recipients containing nutrient solution and then transferred to herbicide solution, (the concentrations used were 0; 0,12; 0,24; 0,36; 0,48% of the equivalent glyphosate acid), and finally, the seedlings were returned to the nutrient solution. in assays iii, iv and v the seeds were placed directly in recipients containing herbicide solution and then the seeds were transferred to nutrient solution. the evaluated parameters were percentage of normal seedlings, seedling, root and hypocotyls length and number of secondary roots. the recommended protocol consisted of the seeds permanence in contact with herbicide solution to 0.12% of the equivalent glyphosate acid for four hours, followed by the transfer of the seeds to nutrient solution until completing five days, using as evaluation parameter the seedling length and the presence of secondary roots. the hydroponics system allows the separation of gm soybean seeds resistant to glyphosate, in five days, after treatment with glyphosate solution.
Sementes geneticamente modificadas: (in)seguran a e racionalidade na ado o de transgênicos no Brasil e na Argentina
Marcos Paulo Fuck,Maria Beatriz Bonacelli
Revista iberoamericana de ciencia tecnolog?-a y sociedad , 2009,
Abstract: Esse artigo analisa as principais quest es relacionadas ao processo de introdu o de sementes geneticamente modificadas no Brasil e na Argentina, com especial aten o às variedades de soja transgênica resistentes ao herbicida à base de glifosato - a soja Rondup Ready (RR). Os dois países adotaram estratégias distintas em rela o à introdu o dessa nova tecnologia em seu território: a Argentina adotou uma política liberalizante, apostando nos transgênicos como forma de amplia o de sua competitividade agrícola; o Brasil adotou uma postura mais cautelosa, mas acabou por liberar o plantio da soja RR em fun o, entre outras coisas, da já expressiva utiliza o dessas sementes pelos produtores rurais (que adquiriram as sementes no mercado paralelo). A discuss o realizada no artigo aponta para a necessidade de políticas públicas que sejam claras em rela o à regulamenta o da produ o e comercializa o de sementes geneticamente modificadas, tomando esses dois casos para ilustrar o debate. This paper examines the main issues related to the introduction of genetically modified seeds in Brazil and Argentina, with particular attention to transgenic soybean varieties resistant to the herbicide glyphosate - the Rondup Ready soybeans (RR). The two countries have adopted different strategies in relation to the introduction of this new technology: the Argentina adopted a policy liberalization, investing in transgenics as a way of increasing its agricultural competitiveness; Brazil adopted a more cautious, but finally liberate the planting of soybean RR depending on, among other things, the already significant use of these seeds by farmers (who purchased the seeds on the parallel market). The discussion emphasizes to the need for public policies that are clear rules regarding the production and commercialization of genetically modified seeds.
Toxicidad en peces de herbicidas formulados con glifosato Toxicity in fishes of herbicides formulated with glyphosate
Maria Alvarez,Isabel T Gimenez,Hugo Saitua,Ricardo D Enriz
Acta Toxicológica Argentina , 2012,
Abstract: En nuestro país existe una gran extensión de hectáreas cultivadas con soja transgénica, la misma ha sido modificada genéticamente para soportar la acción de un herbicida denominado glifosato. Debido a la gran cantidad de formulaciones comerciales que incluyen glifosato es de importancia analizar el impacto ambiental producido por éstas. La evaluacion de la toxicidad aguda de dos herbicidas comerciales formulados con glifosato y de una solución del mismo; frente a peces de la especie Poecilia reticulata "lebistes" acusa que una de las soluciones produce mortalidad del 100 % de los especimenes a 100 μl/l (equivalente a 48 mg/l de principio activo); la otra a 50 μl/l (equivalente a 24 mg/l de principio activo) y la solución formulada con glifosato puro no produce mortalidad aún a concentraciones de 400 mg/l. Utilizando dosis sub letales en función de los datos obtenidos en el ensayo de toxicidad aguda se determinó que a largo plazo especimenes de Cyprinus carpio haematopterus "carpa koi", manifestaron severas alteraciones hematológicas principalmente frente a una de las formulaciones evaluadas. Nowadays, transgenic soya, modified in order to withstand the impact of the herbicide glyphosate, in one of the main crops grown in Argentina. Due to the large number of commercial formulations that include this drug, is important to analyze both, the acute and chronic environmental impact that they cause. Here the acute toxicity of two commercial herbicides glyphosatebased toward the fish Poecilia reticulate "guppy" was evaluated and compared with pure glyphosate solutions. Interestingly, while commercial herbicides formulations induce a 100% of mortality at concentration ranged between 50 and 100 μl/l, the pure glyphosathe does not present mortality even at doses higher than 400 mg/l. When some long term effects toward Cyprinus carpio haematopterus "koi" were determined by using the sub-lethal doses already calculated it was demonstrated that one of the commercial herbicides induces severe haematological alterations.
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