【摘 要】
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The large and rapidly growing world human population is a challenge for world food security.In 2009,the Declaration in the summary report from the World Summit
【机 构】
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Ministry of Education Key Laboratory for Biodiversity and Ecological Engineering,Department of Botan
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The large and rapidly growing world human population is a challenge for world food security.In 2009,the Declaration in the summary report from the World Summit on Food Security held at the Food and Agriculture Organization headquarters in Rome stated that:"The number of people suffering from hunger and poverty now exceeds 1 billion,and that to feed a world population expected to surpass 9 billion in 2050,agricultural output will have to increase by 70％" (IISD & FAO,2009).Two years later,the United Nations Population Fund reinforced that urgency:"In October 2011,Earth's population reaches 7 billion.This global milestone is both a great opportunity and a great challenge" (UNFPA,2011).However,the current population size and growth is not the only challenge.
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