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1.
PLoS One ; 14(10): e0223910, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31665171

RESUMO

Food labels may have both informational and signaling influences on consumer demand. We conduct a choice experiment with over 1,300 subjects to examine the signaling effect of the food product labels on consumer demand for other competing products in the market. Specifically, we focus on the genetically modified (GM) text labeling for fresh produce (strawberries, apples, and potatoes) in the United States. Contrary to some previous studies, our results indicate that the absence-claim label (Not-GM) does not have a negative impact on the demand for related conventional products. Instead, we find that consumer demand for unlabeled products is significantly enhanced with the introduction of presence-claimed GM labels. Our results contribute to the ongoing discussion of the enactment of mandatory labeling for GM foods by the federal U.S. government. Our results suggest that, in the case of direct text disclosure labels, consumers may no longer differentiate between unlabeled products and Not-GM-labeled products after the mandatory GM labeling law is in effect.


Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Rotulagem de Alimentos , Alimentos Geneticamente Modificados , Frutas/genética , Verduras/genética , Adulto , Idoso , Comportamento do Consumidor/economia , Sinais (Psicologia) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Política Pública , Adulto Jovem
2.
PLoS One ; 11(12): e0167865, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27959910

RESUMO

Increased use of intellectual property rights over plant germplasm has led to a complicated landscape for exchange among plant breeders. Our goal was to examine phenotypic and genotypic diversity present in commercially available carrot (Daucus carota L. var. sativus) germplasm in relation to the freedom to operate-the ability for plant breeders to access and use crop genetic diversity. A collection of 140 commercially available carrot cultivars were grown in replicated field trials in the Madison, WI area in 2013 and 2014. Phenotypic measurements were recorded for leaf and root characteristics. Illumina sequencing was used to conduct genotyping by sequencing analysis on all cultivars to understand the range of genetic diversity present. Additionally, the intellectual property rights associated with each cultivar was noted to determine the freedom to operate. We found that although one-third of the commercially available US carrot cultivars in our study are restricted through some form of intellectual property rights, the genetic and phenotypic variability of the protected cultivars does not represent a completely separate group from the available material. Phenotypic analyses including ANOVA and principal components analysis, suggest that many of the traits differed significantly based on market class, but not by whether the cultivar had freedom to operate. The principal components and Fst analyses on the genotyping by sequencing data revealed that carrot market classes (Fst = 0.065) and freedom to operate classes (Fst = 0.023) were not genetically distinct, and that principle components 1 and 2 account for only 10.1% of the total genotypic variation, implying that cultivated carrot germplasm in the US forms an unstructured population. Our findings suggest that the genetic diversity present in carrot cultivars that have freedom to operate is potentially large enough to support carrot breeding efforts in most market classes given present levels of intellectual property protection.


Assuntos
Daucus carota/genética , Variação Genética , Genótipo , Fenótipo , Melhoramento Vegetal/legislação & jurisprudência , Verduras/genética , Daucus carota/economia , Propriedade Intelectual , Melhoramento Vegetal/economia , Estados Unidos , Verduras/economia
3.
J Agric Food Chem ; 62(49): 12067-74, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25389086

RESUMO

Functional small RNAs, such as short interfering RNAs (siRNAs) and microRNAs (miRNAs), exist in freshly consumed fruits and vegetables. These siRNAs can be derived either from endogenous sequences or from viruses that infect them. Symptomatic tomatoes, watermelons, zucchini, and onions were purchased from grocery stores and investigated by small RNA sequencing. By aligning the obtained small RNA sequences to sequences of known viruses, four different viruses were identified as infecting these fruits and vegetables. Many of these virally derived small RNAs along with endogenous small RNAs were found to be highly complementary to human genes. However, the established history of safe consumption of these vegetables suggests that this sequence homology has little biological relevance. By extension, these results provide evidence for the safe use by humans and animals of genetically engineered crops using RNA-based suppression technologies, especially vegetable crops with virus resistance conferred by expression of siRNAs or miRNAs derived from viral sequences.


Assuntos
MicroRNAs/genética , Doenças das Plantas/genética , RNA de Plantas/genética , RNA Interferente Pequeno/genética , RNA Viral/genética , Verduras/genética , Verduras/virologia , Vírus/genética , Doenças das Plantas/virologia , Verduras/economia , Vírus/classificação , Vírus/isolamento & purificação
4.
J Chromatogr A ; 1361: 77-87, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25152493

RESUMO

Based on a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) sample preparation method with Fe3O4 magnetic nanoparticles (MNPs) as the adsorbing material and gas chromatography-tandem mass spectrometry (GC-MS/MS) determination in multiple reaction monitoring (MRM) mode, we established a new method for the determination of multiple pesticides in vegetables and fruits. It was determined that bare MNPs have excellent function as adsorbent when purified, and it is better to be separated from the extract. The amount of MNPs influenced the clean-up performance and recoveries. To achieve the optimum performance of modified QuEChERS towards the target analytes, several parameters including the amount of the adsorbents and purification time were investigated. Under the optimum conditions, recoveries were evaluated in four representative matrices (tomato, cucumber, orange and apple) with the spiked concentrations of 10 µg kg(-1), 50 µg kg(-1)and 200 µg kg(-1) in all cases. The results showed that the recovery of 101 pesticides ranged between 71.5 and 111.7%, and the relative standard deviation was less than 10.5%. The optimum clean-up system improved the purification efficiency and simultaneously obtained satisfactory recoveries of multiple pesticides, including planar-ring pesticides. In short, the modified QuEChERS method in addition to MNPs used for removing impurities improved the speed of sample pre-treatment and exhibited an enhanced performance and purifying effect.


Assuntos
Compostos Férricos/química , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nanopartículas de Magnetita/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Verduras/genética , Cromatografia Gasosa-Espectrometria de Massas/economia , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Espectrometria de Massas em Tandem/economia , Fatores de Tempo , Verduras/química
5.
GM Crops Food ; 3(3): 175-83, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22538234

RESUMO

Genetically engineered (GE) insect-resistant crops that express proteins from Bacillus thuringiensis (Bt) have been widely adopted in the two field crops currently commercially available, Bt cotton and Bt corn. However, the development and commercialization of Bt vegetables has lagged in comparison, which is unfortunate since vegetables tend to be insecticide-intensive crops due to high pest pressure and cosmetic standards required for the market. While it is often stated that consumer choice has played a major role in companies avoiding development of Bt vegetables, this concept requires re-evaluation. In market studies in North America when consumers have been provided basic information about Bt genetic engineering, then given a choice between Bt and conventional sweet corn, they have often preferred the former. Likewise, 77% of consumers in a US survey said they would likely purchase foods produced through biotechnology for their ability to reduce pesticide use. Presently, however, the only commercialized Bt vegetable is sweet corn. Perhaps more critical obstacles to Bt vegetables are their relatively smaller acreages and the cost of government biosafety regulations that inadvertently favor large acreage of field crops because companies can obtain a better return on investment. In developing countries, private-public partnerships may provide the vehicle to bring Bt vegetables to market. However, these can be subverted by misinformation from anti-biotech campaigns, as is the case with Bt eggplant in India. Without the use of Bt vegetables as a tool for integrated pest management, farmers and the general public will not be able to realize the substantial environmental and economic benefits that have been well documented with Bt cotton and Bt corn.


Assuntos
Bacillus thuringiensis/genética , Insetos/fisiologia , Resistência a Inseticidas , Controle Biológico de Vetores , Plantas Geneticamente Modificadas , Verduras/genética , Agricultura/economia , Animais , Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Produtos Agrícolas , Engenharia Genética , América do Norte , Transgenes , Verduras/economia , Verduras/parasitologia , Zea mays/economia , Zea mays/genética , Zea mays/parasitologia
7.
Biotechnology (N Y) ; 11(13): 1543-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7764244

RESUMO

Two approaches were used to assess the safety of the NPTII protein for human consumption using purified E. coli produced NPTII protein that was shown to be chemically and functionally equivalent to the NPTII protein produced in genetically engineered cotton seed, potato tubers and tomato fruit. The NPTII protein was shown, as expected, to degrade rapidly under simulated mammalian digestive conditions. An acute mouse gavage study confirmed that the NPTII protein caused no deleterious effects when administered by gavage at a cumulative target dosage of up to 5000 mg/kg of body weight. This dosage correlates to at least a million fold safety factor relative to the average daily consumption of potato or tomato, assuming all the potatoes or tomatoes consumed contained the NPTII protein. These results, along with previously published information, confirm that ingestion of genetically engineered plants expressing the NPTII protein poses no safety concerns.


Assuntos
Escherichia coli/genética , Engenharia Genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Plantas/genética , Animais , Líquidos Corporais/metabolismo , Digestão , Feminino , Mucosa Gástrica/metabolismo , Mucosa Intestinal/metabolismo , Canamicina Quinase , Masculino , Camundongos , Fosfotransferases (Aceptor do Grupo Álcool)/administração & dosagem , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Segurança , Solanum tuberosum/genética , Verduras/genética
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