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Genetically modified foods - Feed the World? If you want to spark a heated debate at a dinner party, bring up the topic of genetically modified foods. For many people, the concept of genetically altered, high-tech crop production raises all kinds of environmental, health, safety and ethical questions. Particularly in countries with long agrarian traditions - and vocal green lobbies - the idea seems against nature.如果你想在某次晚宴上挑起一场激烈的争论,那就提出转基因食品的话题吧。对许多人来说,高科技的转基因作物生产的概念会带来诸如环境、健康、安全和伦理等方面的各种问题。特别是在有悠久的农业生产传统和主张环保的游说集团的国家里,转基因食品的主意似乎有悖自然。In fact, genetically modified foods are already very much a part of our lives. A third of the corn and more than half the soybeans and cotton grown in the US last year were the product of biotechnology, according to the Department of Agriculture. More than 65 million acres of genetically modified crops will be planted in the US this year. The genetic is out of the bottle.事实上,转基因食品已经成为我们生活重要的一部分。根据农业部的统计,美国去年所种植玉米的13,大豆和棉花的一半以上都是生物技术的产物。今年,美国将种植6500多万英亩的转基因作物。基因妖怪已经从瓶子里跑出来了。Yet there are clearly some very real issues that need to be resolved. Like any new product entering the food chain, genetically modified foods must be subjected to rigorous testing. In wealthy countries, the debate about biotech is tempered by the fact that we have a rich array of foods to choose from - and a supply that far exceeds our needs. In developing countries desperate to feed fast-growing and underfed populations; the issue is simpler and much more urgent: Do the benefits of biotech outweigh the risks?但是,显然还有一些非常现实的问题需要解决。就像任何一种要进入食物链的新食品一样,转基因食品必须经过严格的检验。在富裕的国家里,由于有大量丰富的食品可供选择,而且供应远远超过需求,所以关于生物技术的争论相对缓和一些。在迫切想要养活其迅速增长而又吃不饱的人口的发展中国家,问题比较简单,也更加紧迫:生物技术的好处是否大于风险呢?The statistics on population growth and hunger are disturbing. Last year the worlds population reached 6 billion. And by 2050, the UN estimates, it will probably near 9 billion. Almost all that growth will occur in developing countries. At the same time, the worlds available cultivable land per person is declining. Arable land has declined steadily since 1960 and will decease by half over the next 50 years, according to the International Service for the Acquisition of Agri-Biotech Applications (ISAAA).推荐精选关于人口增长和饥饿的统计数字读来令人感到不安。去年,世界人口达到了60亿。联合国预测,到2D0年,这个数字很可能将接近90亿,而增加的人口几乎都来自发展中国家。与此同时,世界人均耕地正在减少。国际农业生物工程应用技术采购管理局(ISAAA)称,自1960年以来,耕地面积一直持续下降,并将在今后50年减少一半。The UN estimates that nearly 800 million people around the world are undernourished. The effects are devastating. About 400 million women of childbearing age are iron deficient, which means their babies are exposed to various birth defects. As many as 100 million children suffer from vitamin A deficiency, a leading cause of blindness. Tens of millions of people suffer from other major ailments and nutritional deficiencies caused by lack of food.联合国估计,世界上有近8亿人口营养不良。它产生的效应是破坏性的。大约有4亿的育龄妇女体内缺铁,也就是说,她们的婴儿将可能有各种天生的缺陷。数量多达1亿的儿童缺乏维生素A,这是导致失明的主要原因。还有数千万的人患有因食物匮乏而导致的其他严重疾病和营养不良症。 How can biotech help? Biotechnologists have developed genetically modified rice that is fortified with beta-carotene - which the body converts into vitamin A - and additional iron, and they are working on other kinds of nutritionally improved crops. Biotech can also improve farming productivity in places where food shortages are caused by crop damage attribution to pests, drought, poor soil and crop viruses, bacteria or fungi.生物技术对此能做些什么呢?生物技术专家已经培育出了含有胡萝卜素(身体可将之转化为维生素A)和更多铁元素的转基因水稻,目前正在研究培育其他一些增进营养成分的农作物。生物技术还可以帮助提高因虫害、干旱、土壤贫瘠和作物病毒、细菌或真菌导致作物减产而出现食物匮乏的地区的农业生产率。Damage caused by pests is incredible. The European corn borer, for example, destroys 40 million tons of the worlds corn crop annually, about 7% of the total. Incorporating pest-resistant genes into seeds can help restore the balance. In trials of pest-resistant cotton in Africa, yields have increased significantly. So far, fears that genetically modified, pest-resistant crops might kill good insects as well as bad appear unfounded.推荐精选虫害带来的损失令人难以置信。例如,欧洲玉米螟每年毁掉4000万吨玉米,占世界玉米总产量的7。把抗虫害的基因植入种子可以帮助避免这一损失。在非洲进行的抗虫害棉花试验中,棉花的产量已大幅度提高。有人担心,抗虫害的转基因作物不仅将害虫杀死,而且有可能连益虫也一起杀死,但到目前为止,这种担心似乎没有根据。Viruses often cause massive failure in staple crops in developing countries. Two years age, Africa lost more than half its cassava crop - a key source of calories - to the mosaic virus. Genetically modified, virus-resistant crops can reduce that damage, as can drought-tolerant seeds in regions where water shortages limit the amount of land under cultivation. Biotech can also help solve the problem of soil that contains excess aluminum, which can damage roots and cause many staple-crop failures. A gene that helps neutralize aluminum toxicity in rice has been identified.病毒常常在发展中国家造成主要粮食作物的大面积歉收。两年前,花叶病毒使非洲损失了超过一半的木薯,而这种作物是当地人的主要食物。转基因的抗病毒作物可以减少这种损失,就像抗干旱种子在可耕地面积因缺水而受到限制的地区起到的作用一样。含铝过高的土壤会损伤作物的根系并使许多主要作物歉收,对于这种问题生物技术也能帮助解决。目前,研究人员已经识别出一种有助于中和水稻里铝的毒性的基因。Many scientists believe biotech could raise overall crop productivity in developi
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