RESUMO
Paternal biocontainment methods (PBMs) act by preventing pollen-mediated transgene flow. They are compromised by transgene escape via the crop-maternal line. We therefore assess the efficacy of PBMs for transgenic rapeseed (Brassica napus) biocontainment across the United Kingdom by estimating crop-maternal hybridization with its two progenitor species. We used remote sensing, field surveys, agricultural statistics, and meta-analysis to determine the extent of sympatry between the crop and populations of riparian and weedy B. rapa and B. oleracea. We then estimated the incidence of crop-maternal hybridization across all settings to predict the efficacy of PBMs. Evidence of crop chloroplast capture by the progenitors was expanded to a national scale, revealing that crop-maternal gene flow occurs at widely variable rates and is dependent on both the recipient and setting. We use these data to explore the value that this kind of biocontainment can bring to genetic modification (GM) risk management in terms of reducing the impact that hybrids have on the environment rather than preventing or reducing hybrid abundance per se.
Assuntos
Brassica rapa/genética , Hibridização Genética , Cloroplastos/metabolismo , Produtos Agrícolas/genética , Cruzamentos Genéticos , Geografia , Plantas Daninhas/genética , Inquéritos e Questionários , Simpatria , Reino UnidoRESUMO
Food security is an important issue that is of concern for all countries around the world. There are many factors which may cause food insecurity including increasing demand, shortage of supply, trade condition, another countries' food policy, lack of money, high food and oil prices, decelerating productivity, speculation, etc. The food self-sufficiency ratio of Taiwan is only 30.6% weighted by energy in 2007. Total agriculture imports and cereals have increased significantly due to the expansion of livestock and fishery industries and improve living standard. The agriculture sector of Taiwan is facing many challenges, such as: low level of food self-sufficiency, aging farmers, large acreage of set-aside farmlands, small scale farming, soaring price of fertilizers, natural disasters accelerated by climate change, and rapid changes in the world food economy. To cope with these challenges, the present agricultural policy is based on three guidelines: "Healthfulness, Efficiency, and Sustainability." A program entitled "Turning Small Landlords into Large Tenants" was launched to make effective use of idle lands. Facing globalization and the food crisis, Taiwan will secure stable food supply through revitalization of its set-aside farmlands and international markets, and provide technical assistance to developing countries, in particular for staple food crops.