ABSTRACT
BACKGROUND: Lepidopteran pest control in agriculture has become heavily dependent on cultivars that express Bacillus thuringiensis (Bt) toxins as 'plant-incorporated protectants'. However, populations of Spodoptera frugiperda (Smith) in Brazil appear resistant to the Bt traits currently available in commercial soybean cultivars. RESULTS: This study evaluated S. frugiperda life history when feeding on three different Bt soybean cultivars. Cultivars expressing Cry1Ac + Cry1F and Cry1A.105 + Cry2Ab2 + Cry1Ac Bt toxins caused 100% larval mortality in S. frugiperda. Both non-Bt and Cry1Ac-expressing soybean induced transgenerational effects that increased the survival of subsequent generations. A Cry1Ac soybean diet reduced the generation time (T) of S. frugiperda relative to non-Bt soybean, resulting in shorter generation time and more rapid population growth. CONCLUSION: The implications of these results revealed how diet can alter aspects of insect life history and biology, and have important implications for sustainable management of S. frugiperda on soybean. © 2024 Society of Chemical Industry.
ABSTRACT
Intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) do not have a stable 3D structure but still have important biological activities. Jaburetox is a recombinant peptide derived from the jack bean (Canavalia ensiformis) urease and presents entomotoxic and antimicrobial actions. The structure of Jaburetox was elucidated using nuclear magnetic resonance which reveals it is an IDP with small amounts of secondary structure. Different approaches have demonstrated that Jaburetox acquires certain folding upon interaction with lipid membranes, a characteristic commonly found in other IDPs and usually important for their biological functions. Soyuretox, a recombinant peptide derived from the soybean (Glycine max) ubiquitous urease and homologous to Jaburetox, was also characterized for its biological activities and structural properties. Soyuretox is also an IDP, presenting more secondary structure in comparison with Jaburetox and similar entomotoxic and fungitoxic effects. Moreover, Soyuretox was found to be nontoxic to zebra fish, while Jaburetox was innocuous to mice and rats. This profile of toxicity affecting detrimental species without damaging mammals or the environment qualified them to be used in biotechnological applications. Both peptides were employed to develop transgenic crops and these plants were active against insects and nematodes, unveiling their immense potentiality for field applications.
Subject(s)
Intrinsically Disordered Proteins/chemistry , Intrinsically Disordered Proteins/metabolism , Peptides/chemistry , Peptides/metabolism , Plant Proteins/chemistry , Plant Proteins/metabolism , Urease/metabolism , Amino Acid Sequence , Pesticides/toxicity , Structure-Activity Relationship , Urease/chemistryABSTRACT
MAIN CONCLUSION: The structure of the cotton uceA1.7 promoter and its modules was analyzed; the potential of their key sequences has been confirmed in different tissues, proving to be a good candidate for the development of new biotechnological tools. Transcriptional promoters are among the primary genetic engineering elements used to control genes of interest (GOIs) associated with agronomic traits. Cotton uceA1.7 was previously characterized as a constitutive promoter with activity higher than that of the constitutive promoter from the Cauliflower mosaic virus (CaMV) 35S gene in various plant tissues. In this study, we generated Arabidopsis thaliana homozygous events stably overexpressing the gfp reporter gene driven by different modules of the uceA1.7 promoter. The expression level of the reporter gene in different plant tissues and the transcriptional stability of these modules was determined compared to its full-length promoter and the 35S promoter. The full-length uceA1.7 promoter exhibited higher activity in different plant tissues compared to the 35S promoter. Two modules of the promoter produced a low and unstable transcription level compared to the other promoters. The other two modules rich in cis-regulatory elements showed similar activity levels to full-length uceA1.7 and 35S promoters but were less stable. This result suggests the location of a minimal portion of the promoter that is required to initiate transcription properly (the core promoter). Additionally, the full-length uceA1.7 promoter containing the 5'-untranslated region (UTR) is essential for higher transcriptional stability in various plant tissues. These findings confirm the potential use of the full-length uceA1.7 promoter for the development of new biotechnological tools (NBTs) to achieve higher expression levels of GOIs in, for example, the root or flower bud for the efficient control of phytonematodes and pest-insects, respectively, in important crops.
Subject(s)
Gossypium/genetics , 5' Untranslated Regions , Arabidopsis/genetics , Caulimovirus/genetics , Gene Expression Regulation, Plant , Genes, Plant , Genes, Reporter , Genetic Engineering , Gossypium/anatomy & histology , Gossypium/growth & development , Plants, Genetically Modified , Promoter Regions, GeneticABSTRACT
Little is known about the effects of genetically modified corn plants on the foraging of Spodoptera frugiperda (J.E. Smith). Therefore, this study examines whether singular herbicide-tolerant and insect-resistant plants and their stacked events interfere with food preference and oviposition of S. frugiperda. Two non-Bt corn hybrids and three Bt-hybrids, some of them with glyphosate tolerance (GT), were evaluated. Food preference of larvae and biological parameters were assessed. Oviposition preference bioassays involved choice and no choice condition in plants uninfested and previously infested by larvae in a greenhouse and in the field. The results indicate that there is no relationship between preference of larvae and adult moths. Adult females selected preferentially transgenic hybrids, while larvae selected non-Bt hybrid. Fall armyworm larvae avoid Bt-toxin-expressing leaf tissues, survived only on the non-Bt leaf tissues, and showed minor differences in other life-history traits reared on GT and non-transgenic corn leaf tissues. Female moths showed preference for transgenic plants to lay eggs, but with variable output between previously infested and uninfested plants with larvae. The fact that moths preferred Ag 3700RR2 and non-Bt hybrids for oviposition supports the refuge's strategy aiming at producing susceptible individuals. The use of this hybrid must be integrated with a program of control. The results showed also the importance of correct hybrid selection as part of insect resistance management to Bt-plants. The implications of these findings for understanding the impacts of plant-mediated cues on pest behavior in transgenic crop systems are discussed.
Subject(s)
Choice Behavior , Feeding Behavior , Oviposition , Spodoptera/physiology , Zea mays/genetics , Animals , Bacillus thuringiensis Toxins/genetics , Behavior, Animal , Female , Plants, Genetically Modified/geneticsABSTRACT
Cooperative management of pest susceptibility to transgenic Bacillus thuringiensis (Bt) crops is pursued worldwide in a variety of forms and to varying degrees of success depending on context. We examine this context using a comparative socioecological analysis of resistance management in Australia, Brazil, India, and the United States. We find that a shared understanding of resistance risks among government regulators, growers, and other actors is critical for effective governance. Furthermore, monitoring of grower compliance with resistance management requirements, surveillance of resistance, and mechanisms to support rapid implementation of remedial actions are essential to achieve desirable outcomes. Mandated resistance management measures, strong coordination between actors, and direct linkages between the group that appraises resistance risks and growers also appear to enhance prospects for effective governance. Our analysis highlights factors that could improve current governance systems and inform other initiatives to conserve susceptibility as a contribution to the cause of public good.
Subject(s)
Bacillus thuringiensis , Australia , Brazil , India , Insecticide Resistance , Pest Control, Biological , Plants, Genetically Modified , United StatesABSTRACT
O trabalho teve por objetivo avaliar o desempenho da soja submetida a doses de glyphosate em associações com fertilizantes foliares e regulador de crescimento vegetal, visando o processo de reversão do efeito fitotóxico na soja RR2. O experimento foi conduzido entre novembro de 2015 e janeiro de 2016, em casa de vegetação situada na Universidade Federal do Paraná - Setor Palotina. Utilizou-se a cultivar Monsoy 6210 IPRO®. As plantas foram submetidas à aplicação de glyphosate nas doses 0, 720, 1440, 2160 e 2880 g e.a. ha-1 e doses de glyphosate em associação com os produtos: regulador de crescimento vegetal (cinetina 0,09 g L-1, ácido giberélico 0,05 g L-1 e ácido 4-indol-3-butílico 0,05 g L-1) na dose 250ml ha-1, manganês (Mn na forma de um quelato de aminoácido, 62,5 g L-1) na dose de 1L, e o composto de aminoácidos (hidrolisado proteico, ácido fosfórico, hidróxido de potássio e água, 1L ha-1). A aplicação foi realizada no estágio V4. Avaliou-se índice de clorofila, matéria seca de parte aérea e raiz, e sintomas de fitointoxicação na cultura. Os dados foram submetidos a análise de variância, submetidos ao teste de Tukey (p≤0,05) e análise de regressão para o fator dose. Não foram observadas diferenças entre os tratamentos com fertilizantes e regulador vegetal e o herbicida. Os sintomas de fitointoxicação da cultura e os níveis de clorofila foram proporcionais ao aumento de dose do herbicida, porém houve uma recuperação da cultura após 35 DAA. Para matéria seca de raiz e parte aérea das plantas, não foi observada diferença entre os manejos de reversão da fitointoxicação. Trabalhos à campo são necessários para constatação de efeitos dos produtos na fisiologia das plantas visando um possível incremento de produtividade.(AU)
The objective of this work is to evaluate the performance of soybean submitted to glyphosate doses in association with foliar fertilizers and plant growth regulator, aiming the reversal of phytotoxic effect in RR2 soybean. The experiment was conducted between November 2015 and January 2016, in a greenhouse located at the Federal University of Paraná - Setor Palotina. Monsoy 6210 IPRO® was used. The plants were submitted to glyphosate application at 0, 720, 1440, 2160 and 2880 g a. e ha-1 and glyphosate in association with the products: plant growth regulator (kinetin 0.09 g L-1, gibberellic acid). 0.05 g L-1 and 4-indol-3-butyl acid 0.05 g L-1) at the dose 250 ml ha-1, manganese (Mn as an aminoacid chelate, 62.5 g L-1) at a dose of 1L, and the aminoacid compound (protein hydrolysate, phosphoric acid, potassium hydroxide and water, 1L ha-1). The application was performed at stage V4. Chlorophyll index shoot and root dry matter, and phytointoxication symptoms in the crop were evaluated. Data were subjected to analysis of variance, Tukey test (p≤0.05) and regression analysis for the dose factor. No differences were observed between fertilizer and plant regulator treatments and herbicide. Symptoms of crop phytointoxication and chlorophyll levels were proportional to herbicide dose increase, but there was a recovery of culture after 35 DAA. For root and shoot dry matter, no difference was observed between the phytointoxication reversal management. Field work is necessary to verify the effects of products on plant physiology aiming at a possible increase of productivity.(AU)
Subject(s)
Fertilizers/analysis , Plant Growth Regulators , Glycine max/growth & development , Herbicides/analysisABSTRACT
O trabalho teve por objetivo avaliar o desempenho da soja submetida a doses de glyphosate em associações com fertilizantes foliares e regulador de crescimento vegetal, visando o processo de reversão do efeito fitotóxico na soja RR2. O experimento foi conduzido entre novembro de 2015 e janeiro de 2016, em casa de vegetação situada na Universidade Federal do Paraná - Setor Palotina. Utilizou-se a cultivar Monsoy 6210 IPRO®. As plantas foram submetidas à aplicação de glyphosate nas doses 0, 720, 1440, 2160 e 2880 g e.a. ha-1 e doses de glyphosate em associação com os produtos: regulador de crescimento vegetal (cinetina 0,09 g L-1, ácido giberélico 0,05 g L-1 e ácido 4-indol-3-butílico 0,05 g L-1) na dose 250ml ha-1, manganês (Mn na forma de um quelato de aminoácido, 62,5 g L-1) na dose de 1L, e o composto de aminoácidos (hidrolisado proteico, ácido fosfórico, hidróxido de potássio e água, 1L ha-1). A aplicação foi realizada no estágio V4. Avaliou-se índice de clorofila, matéria seca de parte aérea e raiz, e sintomas de fitointoxicação na cultura. Os dados foram submetidos a análise de variância, submetidos ao teste de Tukey (p≤0,05) e análise de regressão para o fator dose. Não foram observadas diferenças entre os tratamentos com fertilizantes e regulador vegetal e o herbicida. Os sintomas de fitointoxicação da cultura e os níveis de clorofila foram proporcionais ao aumento de dose do herbicida, porém houve uma recuperação da cultura após 35 DAA. Para matéria seca de raiz e parte aérea das plantas, não foi observada diferença entre os manejos de reversão da fitointoxicação. Trabalhos à campo são necessários para constatação de efeitos dos produtos na fisiologia das plantas visando um possível incremento de produtividade.
The objective of this work is to evaluate the performance of soybean submitted to glyphosate doses in association with foliar fertilizers and plant growth regulator, aiming the reversal of phytotoxic effect in RR2 soybean. The experiment was conducted between November 2015 and January 2016, in a greenhouse located at the Federal University of Paraná - Setor Palotina. Monsoy 6210 IPRO® was used. The plants were submitted to glyphosate application at 0, 720, 1440, 2160 and 2880 g a. e ha-1 and glyphosate in association with the products: plant growth regulator (kinetin 0.09 g L-1, gibberellic acid). 0.05 g L-1 and 4-indol-3-butyl acid 0.05 g L-1) at the dose 250 ml ha-1, manganese (Mn as an aminoacid chelate, 62.5 g L-1) at a dose of 1L, and the aminoacid compound (protein hydrolysate, phosphoric acid, potassium hydroxide and water, 1L ha-1). The application was performed at stage V4. Chlorophyll index shoot and root dry matter, and phytointoxication symptoms in the crop were evaluated. Data were subjected to analysis of variance, Tukey test (p≤0.05) and regression analysis for the dose factor. No differences were observed between fertilizer and plant regulator treatments and herbicide. Symptoms of crop phytointoxication and chlorophyll levels were proportional to herbicide dose increase, but there was a recovery of culture after 35 DAA. For root and shoot dry matter, no difference was observed between the phytointoxication reversal management. Field work is necessary to verify the effects of products on plant physiology aiming at a possible increase of productivity.
Subject(s)
Fertilizers/analysis , Herbicides/analysis , Plant Growth Regulators , Glycine max/growth & developmentABSTRACT
RESUMEN La papa es afectada por el ataque de Tecia solanivora que causa pérdidas hasta del 80%. Variedades genéticamente modificadas y biocontroladores, pueden ser usados para su manejo. Este estudio pretendió determinó el potencial socioeconómico de pequeños productores de papa de la región Cundiboyacense para la adopción de estas estrategias biotecnológicas, mediante encuestas cara a cara y el uso de metodologías como presupuestos parciales y modelo de regresión logística. Los resultados revelan que el tipo de semilla define la adopción, existiendo un interés por tecnologías que permitan el control de la plaga, por lo cual estarían dispuestos a pagar hasta un 30% más del valor actual por esta. La metodología de presupuestos parciales evidenció un efecto económico positivo en los diferentes escenarios planteados. Se concluyó que los pequeños productores de papa de los municipios analizados cuentan con un alto potencial socioeconómico para la adopción del paquete biotecnológico.
ABSTRACT The potato is affected by the attack of Tecia solanivora that causes losses of up to 80%. Genetically modified varieties and biocontrol agents, can be used for its control. This study aimed to determine the socioeconomic potential of small potato producers in the Cundiboyacense region for the adoption of these biotechnological strategies, through face-to-face surveys and the use of methodologies such as partial budgets and logistic regression model. The results reveal that the type of seed defines adoption, there being an interest in technologies that allow pest control, so they would be willing to pay up to 30% more of the current value for this. The methodology of partial budgets showed a positive economic effect in the different scenarios proposed. It was concluded that small potato producers in the municipalities analyzed have a high socioeconomic potential for the adoption of the biotechnology package.
ABSTRACT
Brassica rapa L. is an annual Brassicaceae species cultivated for oil and food production, whose wild form is a weed of crops worldwide. In temperate regions of South America and especially in the Argentine Pampas region, this species is widely distributed. During 2014, wild B. rapa populations that escaped control with glyphosate applications by farmers were found in this area. These plants were characterized by morphology and seed acidic profile, and all the characters agreed with B. rapa description. The dose-response assays showed that the biotypes were highly resistant to glyphosate. It was also shown that they had multiple resistance to AHAS-inhibiting herbicides. The transgenic origin of the glyphosate resistance in B. rapa biotypes was verified by an immunological test which confirmed the presence of the CP4 EPSPS protein and by an event-specific GT73 molecular marker. The persistence of the transgene in nature was confirmed for at least 4 years, in ruderal and agrestal habitats. This finding suggests that glyphosate resistance might come from GM oilseed rape crops illegally cultivated in the country or as a seed contaminant, and it implies gene flow and introgression between feral populations of GM B. napus and wild B. rapa. The persistence and spread of the resistance in agricultural environments was promoted by the high selection pressure imposed by intensive herbicide usage in the prevalent no-till farming systems.
Subject(s)
Brassica rapa/genetics , Glycine/analogs & derivatives , Herbicide Resistance/genetics , Herbicides/pharmacology , Plant Weeds/genetics , Plants, Genetically Modified/drug effects , Transgenes , Argentina , Brassica napus/genetics , Brassica rapa/drug effects , Ecosystem , Glycine/pharmacology , Plant Weeds/drug effects , Plants, Genetically Modified/genetics , Seeds/drug effects , GlyphosateABSTRACT
Agronomic characteristics of genetically modified (GM) MON 89034 × TC1507 × NK603 × DAS-40278-9 (PowerCore™ Enlist™), MON 89034 × TC1507 × NK603 (PowerCore™), and DAS-40278-9 (Enlist™) corn, a non-GM near-isogenic hybrid, and 2 commercial non-GM hybrids were assessed in a field study to determine if the agronomic performance of the GM corn hybrids is equivalent to that of non-transgenic hybrid corn. The MON 89034 × TC1507 × NK603 × DAS-40278-9 hybrid corn was developed through stacking of 4 individual transgenic events, MON 89034, TC1507, NK603, and DAS-40278-9 by traditional breeding and contains the cry1A.105 and cry2Ab2 (MON 89034), cry1F and pat (TC1507), cp4 epsps (NK603) and aad-1 (DAS-40278-9) transgenes. These transgenes encode the proteins Cry1A.105, Cry2Ab2, and Cry1F, which confer insect resistance, PAT, CP4 EPSPS, and AAD-1, which confer herbicide tolerance. The following agronomic characteristics were assessed in the study: initial and final stand count, seedling vigor, time to silk, time to pollen shed, pollen viability, plant height, ear height, stalk lodging, root lodging, days to maturity, stay green, disease incidence, insect damage, herbicide injury, and yield. The agronomic assessment was conducted in 2 regions of Brazil (Indianopolis-MG; Cravinhos-SP). The agronomic attributes for all GM entries were statistically indistinguishable from the non-GM near-isogenic hybrid. In addition, most of the agronomic assessments fell within the range of the commercial varieties included in the study. Taken together, MON 89034 × TC1507 × NK603 × DAS-40278, MON 89034 × TC1507 × NK603, and DAS-40278-9 were found to be agronomically equivalent to non-GM corn.
Subject(s)
Agriculture , Crosses, Genetic , Herbicides/toxicity , Insecta/physiology , Zea mays/growth & development , Animals , Plants, Genetically Modified , Zea mays/drug effects , Zea mays/geneticsABSTRACT
Fusarium verticillioides is one of the main pathogens of maize, causing ear and stalk rots. This fungus is also able to produce high levels of fumonisins, which have been linked to various illnesses in humans and animals. Previous studies have shown that maize hybrids genetically modified with the cry genes from the bacterium Bacillus thuringiensis (Bt) presented lower incidence of F. verticillioides and fumonisin levels, presumably through the reduction of insects, which could act as vectors of fungi. The aim of this study was to assess the incidence of F. verticillioides and the concentration of fumonisins in Bt and isogenic non-Bt hybrids (2B710Hx, 30F35YG, 2B710, and 30F35, respectively). The samples of 2B710Hx and 30F35YG presented lower F. verticillioides frequency than 2B710 and 30F35 samples. However, there was no statistical difference between fumonisin contamination when Bt and non-Bt samples were compared (P > 0.05). The results suggest that other environmental parameters could possibly trigger fumonisin production during plant development in the field; consequently, other management strategies should be applied to aid controlling fumonisin contamination in maize.
Subject(s)
Fumonisins/analysis , Fusarium/isolation & purification , Mycotoxins/analysis , Zea mays/chemistry , Zea mays/microbiology , Brazil , Plants, Genetically Modified/chemistry , Plants, Genetically Modified/microbiologyABSTRACT
Bacillus thuringiensis Cry2Ab toxin has been used in combination with Cry1Ac for resistance management on the Bt-cotton that is widely planted worldwide. However, little is known regarding Cry2Ab mode of action. Particularly, there is a gap of knowledge on the identification of insect midgut proteins that bind Cry2Ab and mediate toxicity. In the case of Cry1Ab toxin, a transmembrane cadherin protein and glycosyl-phosphatidylinositol (GPI) anchored proteins like aminopeptidase-N1 (APN1) or alkaline-phosphatase (ALP) from Manduca sexta, have been shown to be important for oligomer formation and insertion into the membrane. Binding competition experiments showed that Cry2Ab toxin does not share binding sites with Cry1Ab toxin in M. sexta brush border membrane vesicles (BBMV). Also, that Cry2Ab shows reduced binding to the Cry1Ab binding molecules cadherin, APN1 or ALP. Finally, ligand blot experiments and protein sequence by LC-MS/MS identified APN2 isoform as a Cry2Ab binding protein. Cloning and expression of APN2 confirmed that APN2 is a Cry2Ab binding protein.
Subject(s)
Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , CD13 Antigens/chemistry , Endotoxins/metabolism , Hemolysin Proteins/metabolism , Insect Proteins/chemistry , Manduca/enzymology , Receptors, Cell Surface/chemistry , Amino Acid Sequence , Animals , Bacillus thuringiensis Toxins , Bacterial Proteins/isolation & purification , Binding Sites , CD13 Antigens/isolation & purification , CD13 Antigens/metabolism , Endotoxins/chemistry , Hemolysin Proteins/chemistry , Insect Proteins/isolation & purification , Insect Proteins/metabolism , Insecticide Resistance , Isoenzymes/chemistry , Isoenzymes/isolation & purification , Isoenzymes/metabolism , Ligands , Manduca/genetics , Receptors, Cell Surface/isolation & purification , Receptors, Cell Surface/metabolismABSTRACT
Cotton cultivars expressing Cry proteins are widely used to control lepidopteran pests. The effects of transgenic plants containing insecticidal Cry proteins on non-target species must be comprehended for a better and rational use of this technology for pest management. We investigated the influence of the Bt cotton cultivars NuOPAL and FM 975 on biological parameters of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), a non-target pest of Bt cotton cultivars and on its parasitoid Encarsia desantisi Viggiani (Hymenoptera: Aphelinidae). The experiments were conducted in a climatized room, and the non-transgenic near isolines were used for rearing whiteflies as control hosts. The effects of the Bt cotton cultivars on the period of embryonic and larval development and the percentage of adult emergence of B. tabaci were assessed. The period required for embryonic, larval, and pupal development and the percentage of emergence and longevity of E. desantisi females were determined using Bt cotton-fed and non-Bt cotton-fed B. tabaci as hosts. Both Bt cotton cultivars resulted in a decrease of approximately 20% of adult emergence of B. tabaci. Differently, an increase of approximately 10% of adult emergence of E. desantisi was observed for parasitoids that used hosts fed with both Bt cotton cultivars. However, female parasitoid longevity decreased when their hosts were fed on Bt cotton cultivars. Our data suggest that the use of Bt cotton cultivars in association with the biological control agent E. desantisi could be functional for the management of B. tabaci in Bt cotton crops.
Subject(s)
Gossypium/genetics , Hemiptera/parasitology , Hymenoptera/physiology , Animals , Female , Larva , Plants, Genetically Modified/geneticsABSTRACT
Auxin governs dynamic cellular processes involved at several stages of plant growth and development. In this review, we discuss the mechanisms employed by auxin in light of recent scientific advances, with a focus on synthetic auxins as herbicides and synthetic auxin resistance mechanisms. Two auxin receptors were reported. The plasma membrane receptor ABP1 (Auxin Binding Protein 1) alters the structure and arrangement of actin filaments and microtubules, leading to plant epinasty and reducing peroxisomes and mitochondria mobility in the cell environment. The second auxin receptor is the gene transcription pathway regulated by the SCFTir/AFB ubiquitination complex, which destroys transcription repressor proteins that interrupt Auxin Response Factor (ARF) activation. As a result mRNA related with Abscisic Acid (ABA) and ethylene are transcribed, producing high quantities of theses hormones. Their associated action leads to high production of Reactive Oxygen Species (ROS), leading to tissue and plant death. Recently, another ubiquitination pathway which is described as a new auxin signaling route is the F-box protein S-Phase Kinase-Associated Protein 2A (SKP2A). It is active in cell division regulation and there is evidence that auxin herbicides can deregulate the SKP2A pathway, which leads to severe defects in plant development. In this discussion, we propose that SFCSKP2A auxin binding site alteration could be a new auxinic herbicide resistance mechanism, a concept which may contribute to the current progress in plant biology in its quest to clarify the many questions that still surround auxin herbicide mechanisms of action and the mechanisms of weed resistance.(AU)
Subject(s)
Plant Weeds , Plant Diseases , Herbicide ResistanceABSTRACT
Auxin governs dynamic cellular processes involved at several stages of plant growth and development. In this review, we discuss the mechanisms employed by auxin in light of recent scientific advances, with a focus on synthetic auxins as herbicides and synthetic auxin resistance mechanisms. Two auxin receptors were reported. The plasma membrane receptor ABP1 (Auxin Binding Protein 1) alters the structure and arrangement of actin filaments and microtubules, leading to plant epinasty and reducing peroxisomes and mitochondria mobility in the cell environment. The second auxin receptor is the gene transcription pathway regulated by the SCFTir/AFB ubiquitination complex, which destroys transcription repressor proteins that interrupt Auxin Response Factor (ARF) activation. As a result mRNA related with Abscisic Acid (ABA) and ethylene are transcribed, producing high quantities of theses hormones. Their associated action leads to high production of Reactive Oxygen Species (ROS), leading to tissue and plant death. Recently, another ubiquitination pathway which is described as a new auxin signaling route is the F-box protein S-Phase Kinase-Associated Protein 2A (SKP2A). It is active in cell division regulation and there is evidence that auxin herbicides can deregulate the SKP2A pathway, which leads to severe defects in plant development. In this discussion, we propose that SFCSKP2A auxin binding site alteration could be a new auxinic herbicide resistance mechanism, a concept which may contribute to the current progress in plant biology in its quest to clarify the many questions that still surround auxin herbicide mechanisms of action and the mechanisms of weed resistance.
Subject(s)
Plant Diseases , Plant Weeds , Herbicide ResistanceABSTRACT
Mo-CBP3 is an antifungal protein produced by Moringa oleifera which has been investigated as potential candidate for developing transgenic crops. Before the use of novel proteins, food safety tests must be conducted. This work represents an early food safety assessment of Mo-CBP3, using the two-tiered approach proposed by ILSI. The history of safe use, mode of action and results for amino acid sequence homology using the full-length and short contiguous amino acids sequences indicate low risk associated to this protein. Mo-CBP3 isoforms presented a reasonable number of alignments (>35% identity) with allergens in a window of 80 amino acids. This protein was resistant to pepsin degradation up to 2 h, but it was susceptible to digestion using pancreatin. Many positive attributes were presented for Mo-CBP3. However, this protein showed high sequence homology with allergens and resistance to pepsin digestion that indicates that further hypothesis-based testing on its potential allergenicity must be done. Additionally, animal toxicity evaluations (e.g. acute and repeated dose oral exposure assays) must be performed to meet the mandatory requirements of several regulatory agencies. Finally, the approach adopted here exemplified the importance of performing an early risk assessment of candidate proteins for use in plant transformation programs.
Subject(s)
Antigens, Plant/adverse effects , Dietary Proteins/adverse effects , Food, Genetically Modified/adverse effects , Models, Molecular , Moringa oleifera/metabolism , Plant Proteins/adverse effects , Seeds/metabolism , Allergens/adverse effects , Allergens/chemistry , Allergens/genetics , Allergens/metabolism , Animal Feed/adverse effects , Animal Feed/microbiology , Animals , Antigens, Plant/chemistry , Antigens, Plant/genetics , Antigens, Plant/metabolism , Brazil , Chitin/metabolism , Dietary Proteins/chemistry , Dietary Proteins/metabolism , Digestion , Food Hypersensitivity/etiology , Food Hypersensitivity/prevention & control , Food, Genetically Modified/microbiology , Humans , Ligands , Mitosporic Fungi/growth & development , Moringa oleifera/genetics , Pest Control, Biological/methods , Plant Proteins/chemistry , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Genetically Modified/adverse effects , Plants, Genetically Modified/genetics , Plants, Genetically Modified/metabolism , Protein Isoforms/adverse effects , Protein Isoforms/chemistry , Protein Isoforms/genetics , Protein Isoforms/metabolism , Risk Assessment , Seeds/genetics , Sequence Homology, Amino AcidABSTRACT
An international meeting of genetically modified (GM) food safety assessors from the main importing and exporting countries from Asia and the Americas was held in Buenos Aires, Argentina, between June 26(th) and 28(th), 2013. Participants shared their evaluation approaches, identified similarities and challenges, and used their experience to propose areas for future work. Recommendations for improving risk assessment procedures and avenues for future collaboration were also discussed. The deliberations of the meeting were also supported by a survey of participants which canvassed risk assessment approaches across the regions from which participants came. This project was initiated by Argentine Agri-Food Health and Quality National Service (SENASA, Ministry of Agriculture, Argentina), with the support of the International Life Sciences Institute (ILSI) and other partner institutions. The importance of making all possible efforts toward more integrated and harmonized regulatory oversight for GM organisms (GMOs) was strongly emphasized. This exercise showed that such harmonization is a feasible goal that would contribute to sustain a fluid trade of commodities and ultimately enhance food security. Before this can be achieved, key issues identified in this meeting will have to be addressed in the near future to enable regulatory collaboration or joint work. The authors propose that the recommendations coming out of the meeting should be used as a basis for continuing work, follow up discussions and concrete actions.
Subject(s)
Biotechnology/legislation & jurisprudence , Plants, Genetically Modified , Risk Assessment/standards , Argentina , Congresses as Topic , Consumer Product Safety , Crops, Agricultural , Guidelines as Topic , Risk Assessment/methodsABSTRACT
Durante el desarrollo de los productos biotecnológicos son utilizados materiales y procesos, que pueden estar protegidos por derechos de propiedad intelectual. Para evitar problemas legales en su comercialización, se deben realizar estudios de libertad de operación. Este estudio se realizó sobre una línea genéticamente modificada (GM) de papa (Solanum tuberosum L.) derivada de la variedad Pastusa Suprema, que expresa el gene Cry1Ac de Bacillus thuringiensis, desarrollada por la Corporación de Ciencias Biológicas y la Universidad Nacional de Colombia, Sede Medellín. El punto de partida, fue la deconstrucción del producto, cuyo resultado fue la lista de materiales y procesos usados en el desarrollo del producto. Se buscaron en bases de datos nacionales e internacionales de acceso público, las solicitudes de patentes y patentes relacionadas. En el nivel internacional, se encontraron cuatro solicitudes de patentes y dieciocho patentes relacionadas, la mayoría de las cuales, no han sido solicitadas en Colombia. En el nivel nacional, se encontraron 13 solicitudes de patentes, que han caducado, han sido negadas, abandonadas, desistidas, o están en requerimiento. Se encontró que la variedad tiene registro comercial, pero no título de obtentor. También se examinaron documentos de las instituciones participantes, que contuvieran cláusulas sobre propiedad intelectual, y otros documentos de interés, como los acuerdos de transferencia de materiales (ATM). Se concluye que la libertad de operación puede estar afectada más por problemas detectados en los ATM y en la complejidad de los acuerdos interinstitucionales suscritos, que por los derechos de propiedad intelectual.
During the development of biotechnological products, some materials and processes are used, which can be protected by intellectual property rights (IPR's). In order to avoid legal problems related to their marketing, freedom-to-operate studies need to be done. This study was made on a genetically modified (GM) potato (Solanum tuberous L.) derived from variety "Pastusa Suprema", which expresses the gene cry1Ac from Bacillus thuringiensis, developed by Corporation for Biological Research (Corporación para Investigaciones Biológicas - CIB) and National University of Colombia at Medellín (Universidad Nacional de Colombia, sede Medellín). The starting point was the deconstruction of the product, whose result was the list of materials and processes used in the development of the new product. Patents and related applications were searched in national and international databases. At the international level, four applications and eighteen patents were found, most of which have not been applied for in Colombia. At the national levee, thirteen applications were found, which have expired, have been denied, abandoned, desisted or are currently on request. The plant variety has commercial registration but not breeder's certificate. Documents of the partaker institutions with IP clauses and other documents of interest, such as Material Transfer Agreements (ATM), were examined. It can be concluded that the freedom to operate might be affected for issues related to the ATMs and to the complexity of inter-institutional agreements, rather than for intellectual property rights.
Subject(s)
Biotechnology , Intellectual Property , Solanum tuberosum , Organisms, Genetically ModifiedABSTRACT
En biotecnología de arroz se han logrado avances en transformación genética, con importantes resultados en el mejoramiento genético de variedades elite de las subespecies japónica e índica. Con el propósito de revisar los métodos y los usos agrícolas de la ingeniería genética aplicada al cultivo del arroz, se usaron varias palabras claves en idioma inglés en algunas de las bases de datos de revistas científicas indexadas, disponibles en el Sistema Nacional de Bibliotecas de la Universidad Nacional de Colombia (SINAB), seleccionando documentos publicados entre 2000 y 2011. La base de esta revisión inicial, se complementó con artículos publicados en fechas anteriores, que se consideraron relevantes, debido a que implicaban cambios metodológicos importantes. Desde que se logró producir la primera planta transgénica de arroz a finales de los 80´s, varios protocolos para la transferencia de genes se han empleado con éxito logrando la modificación genética de más de 60 cultivares de arroz. Para ello se han empleado sistemas de transformación tanto directos como indirectos. Se han realizado modificaciones de rasgos importantes en el cultivo, tales como la resistencia a factores bióticos (insectos, hongos, bacterias, virus, nematodos), tolerancia a factores abióticos (salinidad, sequía, altas y bajas temperaturas, inmersión), y mejoramiento de características agronómicas (calidad nutricional, rendimiento, uso de nutrientes, tolerancia a herbicidas).
In rice biotechnology advances have been made in genetic transformation, with significant results in breeding elite varieties of japonica and indica subspecies. In order to review the methods and agricultural uses of genetic engineering applied to rice, calves were used several words in English in some of the databases of scientific journals available in the National Libraries National University of Colombia (SINAB), selecting papers published between 2000 and 2011. Based on this initial review, it addition to some articles published at earlier dates, which were considered relevant because they involved significant methodological changes. Since it was able to produce the first transgenic rice plant in the late 80's, several protocols for gene transfer have been used successfully achieving the genetic modification of more than 60 rice cultivars. For this transformation systems have been used both direct and indirect. There have been significant changes in the crop traits such as resistance to biotic (insects, fungi, bacteria, viruses, nematodes), tolerance to abiotic (salinity, drought, high and low temperatures, immersion), improved features agronomic (nutritional quality, yield, nutrient use, herbicide tolerance).
Subject(s)
Genetic Engineering , Oryza , AgricultureABSTRACT
La producción de alimentos se basa en el uso de diferentes tecnologías agrícolas, que pueden derivar en conflictos entre medioambiente y agricultura. Es significativo estudiar el impacto ambiental de las nuevas tecnologías aplicadas a la agricultura, la más importante de las cuales es la transgénesis. Este trabajo se realizó en la zona algodonera del municipio del Espinal, departamento del Tolima, para la cosecha de algodón del primer semestre de 2009, usando las metodologías de Brookes y Barfoot (2006) y Kovach y colaboradores (1992). Se estudió el efecto ambiental de la aplicación de agroquímicos y el uso de maquinaria agrícola en cultivos de algodón transgénico y convencional. Se recogió información mediante encuestas en veinte fincas productoras de algodón. El análisis de las encuestas se realizó de forma descriptiva, determinando diferencias de tipo cuantitativo y cualitativo para los predios que utilizan la tecnología convencional o la tecnología transgénicas (doble gen, Bt/RR), para luego realizar una correlación con el Enviromental Index Quotient (EIQ). No se encontraron diferencias entre el EIQ de campo de las dos tecnologías, aunque la tecnología transgénica tiene ventajas ambientales en el control de algunas plagas de lepidópteros. En relación con el uso de maquinaria agrícola, se encontró que la tecnología convencional genera menor liberación de CO2, gas de efecto invernadero. La metodología de Brookes y Barfoot puede adaptarse para estudios comparativos de tecnologías agrícolas en países tropicales.
Food production is based on the use of various agricultural technologies, which can lead to conflicts between environment and agriculture. It is important to study the environmental impact of new technologies applied to agriculture, the most important of which is transgenesis. This work was carried out in the cotton belt of the town of Espinal, Tolima Department for the cotton crop in the first half of 2009, through methodologies Brookes & Barfoot (2006) and Kovach et al (1992). We studied the environmental impact of pesticide application and use of agricultural machinery for cultivation of transgenic and conventional cotton. Information was collected through surveys of 20 farms producing cotton. The analysis of the survey was conducted descriptively, by determining differences in quantitative and qualitative for the sites that use conventional technology, and transgenic (Bt gene and double RR / RR), and then make a correlation with the Environmental Index Quotient (EIQ). No differences were found between the fields EIQ the two technologies, although transgenic technology has environmental advantages in the control of some lepidopteran pests. In connection with the use of agricultural machinery, was found to conventional technology generates less release of CO2, greenhouse gas. The Brookes and Barfoot methodology could be adapted in comparative studies of agricultural technologies in tropical countries.