RESUMEN
The coronavirus disease 2019 (COVID-19) pandemic has generated significant economic loss and an unprecedented challenge to people's livelihoods. Using household data collected in November 2020, this study shows that the COVID-19 outbreak has significantly affected consumers' perceptions and consumption of genetically modified (GM) food in China. Their perceptions and purchase intentions have turned more negative, and their actual purchase of GM food has decreased after the COVID-19 outbreak. The study's results also indicate that consumers with more knowledge of genetic modification technology are less likely to change their perceptions of GM food.
Asunto(s)
COVID-19 , Alimentos Modificados Genéticamente , Encuestas y Cuestionarios , Comportamiento del Consumidor , IntenciónRESUMEN
The economic benefits of insect-resistant genetically modified (GM) crops have been well documented, but the impact of such crops and the consequent reduction in pesticide use on farmers' health remains largely unknown. Through the analysis of the data collected from the physical examination from farmers in China, we show that GM rice significantly reduces pesticide use and the resultant not only visible but also invisible adverse effects on farmers' neurological, hematological, and electrolyte system. Hence, the commercialization of GM rice is expected to improve the health of farmers in developing countries, where pesticide application is necessary to mitigate crop loss.
Asunto(s)
Grano Comestible/efectos de los fármacos , Grano Comestible/genética , Agricultores , Oryza/efectos de los fármacos , Oryza/genética , Plaguicidas/efectos adversos , Plantas Modificadas Genéticamente/efectos de los fármacos , Plantas Modificadas Genéticamente/genética , China , Alimentos Modificados Genéticamente , Humanos , Enfermedades Profesionales/etiología , Enfermedades Profesionales/prevención & control , Salud LaboralRESUMEN
Despite the widespread adoption of Bt cotton, farmers still spray excessive pesticides in their cotton fields. In contrast to scientists who always use high quality seeds in the laboratory and/or experimental fields, farmers may plant low quality seeds with a low expression of Bt toxin. How does the expression of Bt toxin influence farmers' pesticide use? On the basis of a plot-level survey and laboratory test data, this study shows that pesticide use on one cotton plot is influenced not only by the expression of Bt crops in this plot, but also by the average expression in the village in the early stage of the cotton growing season. In other words, high expression of Bt toxin benefits not only the farmers who plant the varieties but also all the other villagers.
Asunto(s)
Agricultura , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/toxicidad , Endotoxinas/metabolismo , Endotoxinas/toxicidad , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidad , Animales , Toxinas de Bacillus thuringiensis , Lepidópteros/fisiología , Modelos Teóricos , Control Biológico de Vectores , PlaguicidasRESUMEN
Based on farm field plot level survey data and laboratory test, we examine the determinants of the expression of Bt toxin in China's Bt cotton production. The results show that the expression of Bt toxin differs significantly among varieties. Even for the same variety the expression of Bt toxin also varies substantially among villages and among farmers in the same village. Econometric analyses show that after controlling for the effects of varieties and locations (or villages), farm management, particular applications of phosphate and potash fertilizers, and manure, has significant positive effects on Bt toxin expression in farmer's fields. In contrast to previous studies which showed that nitrogen fertilizer has a positive impact on expression of Bt toxin, this study shows that nitrogen fertilizer has no significant impact on expression of Bt toxin in farmer's fields. On the other hand, the expression of Bt toxin has a positive relationship with phosphate fertilizer, potash fertilizer and manure application.
Asunto(s)
Agricultura , Bacillus thuringiensis/genética , Gossypium/genética , Plantas Modificadas Genéticamente/genética , Toxinas Bacterianas , China , Gossypium/crecimiento & desarrollo , Humanos , Insecticidas/metabolismo , Plantas Modificadas Genéticamente/crecimiento & desarrolloRESUMEN
In the context of genetically modified crops expressing the Bacillus thuringiensis (Bt) toxin, a 'refuge' refers to a crop of the same or a related species that is planted nearby to enable growth and reproduction of the target pest without the selection pressure imposed by the Bt toxin. The goal of this study is to discuss the role of natural refuge crops in slowing down the buildup of resistance of cotton bollworm (CBW), and to evaluate China's no-refuge policy for Bt cotton. We describe in detail the different factors that China should consider in relation to the refuge policy. Drawing on a review of scientific data, economic analyses of other cases, and a simulation exercise using a bio-economic model, we show that in the case of Bt cotton in China, the no-refuge policy is defensible.
Asunto(s)
Proteínas Bacterianas/genética , Endotoxinas/genética , Gossypium/genética , Proteínas Hemolisinas/genética , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/farmacología , China , Endotoxinas/farmacología , Gossypium/parasitología , Proteínas Hemolisinas/farmacología , Control de Insectos , Resistencia a los Insecticidas/genética , Modelos Económicos , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/genética , Mariposas Nocturnas/patogenicidad , Enfermedades de las Plantas/economía , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/prevención & control , Plantas Modificadas GenéticamenteRESUMEN
This paper develops a dynamic model of the evolution of pest a population and pest resistance to characterize the socially optimal refuge strategy for managing a pest's resistance to genetically modified crops. Previous theoretical economic analyses of this problem focus on steady states; we also address refuge policies along the optimal path to the final equilibrium. To elaborate on our theoretical analysis of the resistance problem, we develop a simulation model calibrated to cotton (Gossypium spp.) production in China. Our results show the importance of fitness cost as a determinant of the qualitative nature of optimal refuge policies.