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1.
Indian J Biochem Biophys ; 2022 Aug; 59(8): 800-807
Article | IMSEAR | ID: sea-221559

ABSTRACT

Aphids are one of the most devastating pests, affecting the potential yield and quality ofBrassica juncea. In the current study, we have attempted to pyramid two transgenic lines containing chickpea lectin (CHPL, P1) and urdbean protease inhibitor (UPI, P2) in each under the phloem specific rolC promoter, through conventional breeding approach. In the derived F2 population, both lectin and protease inhibitor genes were segregating in a 9:3:3:1 ratio (p-value: 0.81), indicative of a single copy of the transgenes in the parents. Furthermore, the parental, as well as pyramided progenies were evaluated for their potential resistance to aphids in terms of mortality and natality. The lines containing both the transgenes were found to be superior over single gene transgenics as a higher mortality rate (96%) was found in F2on the 9th day as compared to single gene transgenics (86% and 80% in P1 and P2 respectively). A significant decrease in the number of nymphs was observed in P1 and P2 but most in F2 plants as almost 43, 32.08, and 107.5 times decrease in the number of nymphs was found in P1, P2, and F2 individuals over control. Expression profiling was done to see if there was any impact of gene pyramiding on the expression pattern of both transgenes before and after aphid treatment, and no significant changes were observed, indicating constitutive expression of transgenes in pyramided lines also. In conclusion, pyramided lines were found to be promising and were superior for aphid resistance.

2.
Indian J Biochem Biophys ; 2022 Aug; 59(8): 800-807
Article | IMSEAR | ID: sea-221558

ABSTRACT

Aphids are one of the most devastating pests, affecting the potential yield and quality ofBrassica juncea. In the current study, we have attempted to pyramid two transgenic lines containing chickpea lectin (CHPL, P1) and urdbean protease inhibitor (UPI, P2) in each under the phloem specific rolC promoter, through conventional breeding approach. In the derived F2 population, both lectin and protease inhibitor genes were segregating in a 9:3:3:1 ratio (p-value: 0.81), indicative of a single copy of the transgenes in the parents. Furthermore, the parental, as well as pyramided progenies were evaluated for their potential resistance to aphids in terms of mortality and natality. The lines containing both the transgenes were found to be superior over single gene transgenics as a higher mortality rate (96%) was found in F2on the 9th day as compared to single gene transgenics (86% and 80% in P1 and P2 respectively). A significant decrease in the number of nymphs was observed in P1 and P2 but most in F2 plants as almost 43, 32.08, and 107.5 times decrease in the number of nymphs was found in P1, P2, and F2 individuals over control. Expression profiling was done to see if there was any impact of gene pyramiding on the expression pattern of both transgenes before and after aphid treatment, and no significant changes were observed, indicating constitutive expression of transgenes in pyramided lines also. In conclusion, pyramided lines were found to be promising and were superior for aphid resistance.

3.
Estud. av ; 33(95): 271-284, 2019.
Article in Portuguese | LILACS | ID: biblio-1008463

ABSTRACT

Objetivamos discutir os principais argumentos que estão envolvidos no debate sobre a cientificidade do Princípio de Equivalência Substancial (PES), que afirma serem os OGM quimicamente equivalentes aos organismos selecionados pelas técnicas tradicionais de melhoramento, não requerendo, portanto, estudos toxicológicos adicionais. Problematizamos a cientificidade do PES, especialmente no que diz respeito à questão propriamente química. De fato, o PES estrutura-se conceitualmente na comparação quantitativa entre alguns componentes químico-biológicos da planta transgênica e os da não transgênica. Nesse sentido, as análises químicas propostas não conseguem relacionar sozinhas os possíveis efeitos bioquímicos, toxicológicos e imunológicos dos alimentos transgênicos, pois o princípio restringe as análises à composição química, molecular e analítica dos transgênicos. Emerge assim o problema do locus da incerteza científica, seja como questão epistemológica, seja como questão normativa e moral.


We aim to discuss the main arguments involved in the debate on the scientificity of the Principle of Substantial Equivalence (PSE), which claims that GMOs are chemically equivalent to organisms selected by traditional breeding techniques and therefore do not require additional toxicological studies. We question the scientific character of the PSE, especially with regard to the chemical question itself. Indeed, the PSE is conceptually structured in the quantitative comparison between some chemical--biological components of the transgenic plant and those of the non-transgenic plant. In this sense, the proposed chemical analyses cannot by themselves assess the possi-ble biochemical, toxicological and immunological effects of transgenic foods, since the principle restricts the analysis to the chemical, molecular and analytical composition of transgenics. This gives rise to the problem of the locus of scientific uncertainty, whether as an epistemological question or as a normative and moral issue.


Subject(s)
Humans , Male , Female , Risk , Organisms, Genetically Modified , Precautionary Principle , Genetic Structures , Good Manipulation Practices , Molecular Biology , Food, Genetically Modified
4.
Electron. j. biotechnol ; 19(4): 52-61, July 2016. ilus
Article in English | LILACS | ID: lil-793953

ABSTRACT

Background: Introgression of transgenes from crops to their wild species may enhance the adaptive advantage and therefore the invasiveness of and weedy forms. The study evaluated the effect of Africa Biofortified Sorghum (ABS) genes from ABS event 188 on the vegetative and reproductive features of the F2 populations derived from crosses with Sorghum bicolor subsp. drummondii. Results: F1 populations were obtained from reciprocal crosses involving ABS event 188 and its null segregant with inbred weedy parents from S. bicolor subsp. drummondii. Four F2 populations and four parental populations were raised in RCBD with 4 replications in a confined field plot for two seasons. Vegetative and reproductive traits were evaluated. The vigour shown in the F2 populations from the reciprocal crosses involving ABS event 188 and S. bicolor subsp. drummondii was similar to that in the crosses involving the null segregant and S. bicolor subsp. drummondii. Differences in vegetative and reproductive parameters were observed between the parental controls and the F2 populations. Examination of the above and below ground vegetative biomass showed lack of novel weedy related features like rhizomes. Conclusions: Therefore, release of crops with ABS 188 transgenes into cropping systems is not likely to pose a risk of conferring additional adaptive advantage in the introgressing populations. The interaction of ABS genes in weedy backgrounds will also not have an effect towards enhancing the weedy features in these populations.


Subject(s)
Plants, Genetically Modified , Sorghum/genetics , Germination , Crosses, Genetic , Sorghum/growth & development , Hybrid Vigor , Hybridization, Genetic
5.
Arq. Inst. Biol ; 82: 1-7, 2015. tab, graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1026177

ABSTRACT

O objetivo deste trabalho foi avaliar a eficiência do fungo Beauveria bassiana (isolado CG 716) no manejo de Spodoptera frugiperda e Rhopalosiphum maidis em milho. Diante disso, montou-se um experimento em blocos ao acaso, utilizando parcelas subdivididas, contendo dez tratamentos e quatro repetições. Os tratamentos foram: B. bassiana , formulado em óleo vegetal, nas doses de 2,0, 4,0 e 6,0 x 1012 conídios ha-1, lambda-cialotrina (7,5 i.a. ha-1) e testemunha (sem aplicação). As aplicações foram realizadas a partir dos 10 dias após a emergência (DAE) das plantas, sendo repetidas aos 16, 23 e 31 DAE. As avaliações foram realizadas semanalmente coletando-se dez plantas consecutivas por parcela e armazenadas em sacos plásticos, para posterior destruição do cartucho e contagem de lagartas, pulgões e inimigos naturais em laboratório. Não ocorreram diferenças significativas em populações de S. frugiperda e R .maidis em lavouras de milho submetidas ou não a aplicações de defensivos; entretanto, na variedade convencional, aos 40 DAE, foi constatado que um maior número médio pulgõessob aplicação do bioinseticida na dosagem de 2,0 x 1012 conídios ha-1. B. bassiana ,em associação com a tecnologia Bt , não produziu resultados satisfatórios no controle de S. frugiperda e R. maidis nas condições em que foi testado.(AU)


The objective of this study work was to evaluate the efficiency of the fungus Beauveria bassiana (isolate CG 716) to control Spoodptera frugiperda and Rhopalosiphum maidis on maize. Front this, was set up in randomized blocks split plots design, with 10 treatments and four replications. Treatments were applied to plots: B. bassiana formulated in vegetable oil at doses of 2.0, 4.0 and 6.0 x 1012 conidia ha-1, lambda-cyhalothrin (7.5 a.i. ha-1) and control (no application). Applications were made weekly. Assessments were performed before each application of the products, collecting 10 consecutive plants per plot for subsequent and storing in plastic bag from destruction of the whorl of maize and counting the number of fall armyworm larvae, aphids and natural enemies in laboratory. There were no significant differences among treatments in relation to the population of S. frugiperda larvae and R. maidis in corn fields treated or not treated with of defensives applications, however, higher number of R. maidis was observed on the conventional cultivar at 40 days after emergence (DAE) treated with the bioinsecticide B. bassiana at a dose of 2.0 x 1012 conidia ha-1. B. bassiana associated with Bt technology does not show satisfactory results to control S. frugiperda .(AU)


Subject(s)
Pest Control, Biological , Efficacy , Spodoptera , Zea mays , Beauveria , Pest Control , Fungi
6.
J Environ Biol ; 2013 Jan; 34(1): 67-73
Article in English | IMSEAR | ID: sea-148492

ABSTRACT

The effectiveness of commercial Bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow in the insect fauna under field conditions were studied keeping in view the need to assess bioefficacy and biosafety of Bt-transgenic cotton. There were no significant differences in oviposition by Helicoverpa armigera on Bt-transgenic and non-transgenic cottons (9.2 versus 9.6 eggs plants-100), while the numbers of H. armigera larvae were significantly more on non-transgenic than on Bt-transgenic (10.4 versus 4.0 larvae plants-100) cotton. The Bt-cotton had significantly more number of mature opened bolls (9.6 versus 4.4 bolls plant-1), lower bollworm damage (12.8 versus 40.2% bolls damaged), and higher seedcotton yield (667.7 versus 231.7 kg ha-1). Population of cotton leafhopper, Amrasca biguttula biguttula was lower (582.2 versus 732.2 leafhoppers plants-100), while that of whitefly, Bemisia tabaci was higher on Bt-transgenic (65.2 versus 45.6 whiteflies plants-100) than on non-transgenic cotton. There was no significant influence of Bt-transgenic cotton on abundance of natural enemies of crop pests – chrysopids (9.6 versus 8.4 chrysopids plants-100), ladybird beetles (16.0 versus 10.8 ladybirds plants-100), and spiders (128.4 versus 142.8 spiders plants-100). There were no significant differences in H. armigera egg (19.8 versus 20.9%), larval (7.4 versus 9.6%), and larval-pupal (1.3 versus 2.9%) parasitism on Bt-transgenic and non-transgenic cottons in the farmer’s fields. The parasitism in larvae of H. armigera was far lower than that of the eggs, which might be because of early mortality of H. armigera prior to parasitoid development in the host larvae. Although, Cry1Ac Bt toxin was detected in Cheilomenes sexmaculatus, chrysopids, A. bigutulla bigutulla, Thrips tabaci, Myllocerus sp., Oxycarenus laetus, Dysdercus koenigii, spiders, bugs, and grasshoppers, no significant differences were observed in their abundance on Bt-transgenic and non-transgenic cottons, suggesting that there were no adverse effects of Bt-cotton on the arthropod diversity under field conditions.

7.
J Biosci ; 2012 Mar; 37 (1): 167-197
Article in English | IMSEAR | ID: sea-161654

ABSTRACT

During the efficient genetic transformation of plants with the gene of interest, some selectable marker genes are also used in order to identify the transgenic plant cells or tissues. Usually, antibiotic- or herbicide-selective agents and their corresponding resistance genes are used to introduce economically valuable genes into crop plants. From the biosafety authority and consumer viewpoints, the presence of selectable marker genes in released transgenic crops may be transferred to weeds or pathogenic microorganisms in the gastrointestinal tract or soil, making them resistant to treatment with herbicides or antibiotics, respectively. Sexual crossing also raises the problem of transgene expression because redundancy of transgenes in the genome may trigger homology-dependent gene silencing. The future potential of transgenic technologies for crop improvement depends greatly on our abilities to engineer stable expression of multiple transgenic traits in a predictable fashion and to prevent the transfer of undesirable transgenic material to non-transgenic crops and related species. Therefore, it is now essential to develop an efficient marker-free transgenic system. These considerations underline the development of various approaches designed to facilitate timely elimination of transgenes when their function is no longer needed. Due to the limiting number of available selectable marker genes, in future the stacking of transgenes will be increasingly desirable. The production of marker-free transgenic plants is now a critical requisite for their commercial deployment and also for engineering multiple and complex trait. Here we describe the current technologies to eliminate the selectablemarker genes (SMG) in order to develop marker-free transgenic plants and also discuss the regulation and biosafety concern of genetically modified (GM) crops.

8.
Ciênc. Saúde Colet. (Impr.) ; 17(2): 359-368, fev. 2012.
Article in Portuguese | LILACS | ID: lil-610690

ABSTRACT

O presente artigo apresenta uma revisão sobre a rotulagem de produtos que apresentem em sua composição Organismos Geneticamente Modificados (OGM), também denominados de transgênicos. São abordadas as convenções, as leis e as normas referentes a esses produtos dispostos no mercado, a adequação dos mesmos às normas vigentes e sua aceitação pela sociedade. Dispõe também sobre a importância do princípio da precaução na avaliação da aplicação de novas tecnologias ou de tecnologias das quais não se conhece ou existam conhecimentos científicos relevantes quanto aos seus potenciais riscos ao meio ambiente, à saúde humana e à sociedade.


This article presents a review about the labeling of products that have Genetically Modified Organisms (GMO), also called transgenic elements in their composition. It addresses the conventions, laws and regulations relating to such products currently governing the market, the adequacy of these existing standards and their acceptance by society. It also examines the importance of the cautionary principle when assessing the application of new technologies or technologies where little is known or where there is no relevant scientific knowledge about the potential risks to the environment, human health and society.


Subject(s)
Humans , Disclosure , Organisms, Genetically Modified , Product Labeling , Brazil
9.
J Biosci ; 2011 Jun; 36(2): 363-376
Article in English | IMSEAR | ID: sea-161557

ABSTRACT

High levels of expression of the cry1Ac gene from Bacillus thuringiensis cannot be routinely achieved in transgenic plants despite modifications made in the gene to improve its expression. This has been attributed to the instability of the transcript in a few reports. In the present study, based on the genetic transformation of cotton and tobacco, we show that the expression of the Cry1Ac endotoxin has detrimental effects on both the in vitro and in vivo growth and development of transgenic plants. A number of experiments on developing transgenics in cotton with different versions of cry1Ac gene showed that the majority of the plants did not express any Cry1Ac protein. Based on Southern blot analysis, it was also observed that a substantial number of lines did not contain the cry1Ac gene cassette although they contained the marker gene nptII. More significantly, all the lines that showed appreciable levels of expression were found to be phenotypically abnormal. Experiments on transformation of tobacco with different constructs expressing the cry1Ac gene showed that in vitro regeneration was inhibited by the encoded protein. Further, out of a total of 145 independent events generated with the different cry1Ac gene constructs in tobacco, only 21 showed expression of the Cry1Ac protein, confirming observations made in cotton that regenerants that express high levels of the Cry1Ac protein are selected against during regeneration of transformed events. This problem was circumvented by targeting the Cry1Ac protein to the chloroplast, which also significantly improved the expression of the protein.

10.
Hist. ciênc. saúde-Manguinhos ; 17(2): 455-470, abr.-jun. 2010.
Article in Portuguese | LILACS | ID: lil-552905

ABSTRACT

Em 2007, a Agência Nacional de Vigilância Sanitária promoveu uma consulta pública on line para receber contribuições à Proposta de Regulamento Técnico de avaliação de segurança de alimentos transgênicos. Este artigo descreve o contexto e os resultados da pesquisa que identificou os principais enquadramentos e agendas construídos pelos jornais Folha de S.Paulo e O Estado de S.Paulo sobre assuntos ligados ao objeto dessa consulta, a fim de avaliar a pluralidade de informações oferecidas como potencial subsídio à participação política. A cobertura jornalística enfocada se apresentou, em geral, fragmentada; 70 por cento das matérias ofereceram visões incompletas sobre o contexto da consulta.


Subject(s)
Food, Genetically Modified , Health Surveillance , Mass Media , Scientific Communication and Diffusion , Brazil
11.
Estud. av ; 24(70): 149-164, 2010. ilus, tab
Article in Portuguese | LILACS | ID: lil-566049

ABSTRACT

A expectativa de o crescimento populacional atingir 9 bilhões de habitantes em 2050 em adição às questões da sustentabilidade e do aquecimento global nos desafiam a aumentar a oferta de alimentos. Uma metodologia alternativa que contribua para a redução do impacto desse cenário envolve a biotecnologia, que, nas últimas décadas, trouxe marcantes oportunidades tecnológicas na agricultura, resultando em relevante desenvolvimento na obtenção de novas variedades de plantas, na melhoria da qualidade de diversos alimentos e atualmente também na bioenergia. As técnicas biotecnológicas envolvendo os marcadores moleculares, a genômica e a transformação genética estão transformando a agricultura e são discutidas neste artigo.


The expected population growth to reach 9 billion by 2050 in addition to issues of sustainability and global warming challenges us to increase the supply of food. An alternative approach to help reducing the impact of this scenario involves biotechnology which in recent decades has brought remarkable technological opportunities in the agriculture that resulted in relevant development in obtaining new plant varieties, improved quality of different foods, and now also in bioenergy. The biotechnology techniques involving molecular markers, genomics and genetic transformation are transforming agriculture and will be discussed in this article.


Subject(s)
Food, Genetically Modified/supply & distribution , Biofuels , Biotechnology/trends , Food Production , Genomics/trends , Genetic Enhancement/methods , Genetic Markers , Biomarkers
13.
Electron. j. biotechnol ; 10(3): 452-467, July 2007. tab
Article in English | LILACS | ID: lil-640493

ABSTRACT

Tobacco is the most commonly used plant for expression of transgenes from a variety of organisms, because it is easily grown and transformed, it provides abundant amounts of fresh tissue and has a well-established cell culture system. Many bacterial proteins involved in the synthesis of commercial products are currently engineered for production in tobacco. Bacterial enzymes synthesized in tobacco can enhance protection against abiotic stresses and diseases, and provide a system to test applied strategies such as phytoremediation. Examples of bacterial gene expression in tobacco include production of antigen proteins from several human bacterial pathogens as vaccines, bacterial proteins for enhancing resistance against insects, pathogens and herbicides, and bacterial enzymes for the production of polymers, sugars, and bioethanol. Further improvements in the expression of recombinant proteins and their recovery from tobacco will enhance production and commercial use of these proteins. This review highlights the dynamic use of tobacco in bacterial protein production by examining the most relevant research in this field.

14.
Rev. biol. trop ; 55(2): 347-364, jun. 2007.
Article in Spanish | LILACS | ID: lil-637586

ABSTRACT

Genetically modified crops: promises and good intentions are not enough (refutation to Espinoza et al. 2004, Rev. Biol. Trop. 52 (3): 727-732). The arguments presented by Espinoza et al. in their paper "Relationship of genetically modified crops with the environment and health of the Costa Rican human population" published in this journal (Rev. Biol. Trop. 52: 727-732, 2004) are questioned and refuted. The arguments are confronted with evidence offered by scientists and national and international independent organizations around the world (e.g. World Health Organization, Consumers international, Physicians and Scientists for Responsible Application of Science and Technology, international Union for Conservation of Nature and Natural Resources, the Council of the University of Costa Rica, and the independent Science Panel) showing the current uncertainty and limitations of science in this area, as well as those of proposed and applied biosafety approaches. Environment, biodiversity and food security are so important and basic matters, that there is need of serious testing, particularly when promises seem to be based on environmentally dangerous ideas promoted half a century ago by the so called "green revolution". Debate should continue, based on a holistic analysis of facts and with ethical reasoning, avoiding emotional positions that can confuse virtual reality with reality. Rev. Biol. Trop. 55 (2): 347-364. Epub 2007 June, 29.


Se refutan y cuestionan los razonamientos expuestos por las autoras en el artículo "Relación de los cultivos modificados genéticamente con el ambiente y la salud de la población costarricense" publicado en esta revista por Espinoza et al. (52: 727-732, 2004). Para ello se contraponen éstos con las evidencias expuestas y analizadas tanto por científicos como por organizaciones nacionales e internacionales independientes de diverso tipo en diferentes lugares del mundo (e.g. Organización Mundial de la Salud, internacional de Consumidores, Médicos y Científicos por una Aplicación Responsable de la Ciencia y la Tecnología, Unión internacional para la Conservación de la Naturaleza, Consejo Universitario de la Universidad de Costa Rica y el Panel de Ciencias independiente), que confirman la incertidumbre y limitaciones actuales de la ciencia en esta área, así como de los mecanismos de bioseguridad propuestos y puestos en vigor. En materias tan importantes y básicas para la supervivencia como las que nos ocupan -el ambiente, la biodiversidad y la seguridad alimentaria- no es prudente apostar a promesas basadas en la misma lógica promocionada desde hace poco más de cinco décadas por la denominada "revolución verde". Es necesario continuar este debate basado en el análisis holístico de los hechos, así como en razonamientos éticos, evitando caer en posiciones emocionales que llegan a confundir la realidad virtual con la verdadera realidad.


Subject(s)
Humans , Consumer Product Safety , Crops, Agricultural/genetics , Plants, Genetically Modified , Costa Rica , Risk Assessment
15.
Rev. biol. trop ; 52(3): 727-732, sept. 2004.
Article in Spanish | LILACS | ID: lil-501709

ABSTRACT

Genetic engineering and the food derived from genetically modified crops (GMCs) have been the center of debate worldwide, as has occurred historically with the advent of new technologies. Questions are derived from the potential impact of GMCs to the environment and the safety of the products to the consumers. In relation to the first inquiry, practice has been oriented to a case-by-case-study, according to the own characteristics of the GMC, in order to minimize its impact in the environment. Scientific studies in diverse latitudes of the world have demonstrated that GMCs in the market showed no adverse effects related to this issue. In relation to food derived from the GMCs, rigorous evaluation protocols have been developed and approved by FAO and WHO to guarantee the innocuousness of these products. Up to the moment, no contraindications for human health have been pointed out for the products that are available today in the market. In the particular case of Costa Rica, the country has established since the 90s a regulatory biosafety framework for the management of the GMCs, safeguarding the biodiversity of the country and the health of consumers. At the same time the country has made significant public and private investments in the field that allowed the country to obtain a leading position in biosafety in the region and genetic engineering research at national research centers. Any attempt to restrict or prohibit these activities in the country, will put in risk the previously described investment, will affect the generation of new knowledge for decision making and the leadership in the field, preventing the benefits derived from this promising technology.


Subject(s)
Humans , Food, Genetically Modified , Risk Assessment/methods , Consumer Product Safety/standards , Public Health , Food, Genetically Modified/adverse effects , Costa Rica , Risk Factors , Consumer Product Safety/legislation & jurisprudence
16.
Chinese Journal of Marine Drugs ; (6)2001.
Article in Chinese | WPRIM | ID: wpr-683919

ABSTRACT

Chitinase (EC3.2.1.14) catalyses the reaction of hydrolyzing the chitin into N acetylglucosamine (GlcNac) and (GlcNac) n.With the in deep study of chitinase,more and more biological function of chitinase appeared obviously.Now,we introduce the actualities of chitinase research,including substrate specificity,physiological function,antifungi function and transgenics, et al .

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