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据估计,全世界盐性土地大约有95亿公顷,加上有些地区农业开发困难,盐土面积还在不断增加。在那些干旱、半干旱国家,这个问题更加突出。地表蒸腾,灌溉和涨潮所析出的盐分都在作物根际区积累。巴基斯坦每年每公顷灌溉面积就积累盐分2.5吨,因此每年大约有4万公顷土地不能从事农业生产,经济损失达30亿美元。盐性土壤通过化学处理和排水可以改良,但是,对发展中国家来说,采取此种方案来解决这一巨大问题,在经济上就感到吃不消。另一途径是运用遗传工程,培育耐盐作物种类,IPSR作物育种研究所选用世界上最主要的作物——小麦来进行这一尝试。小麦对盐非常敏感,世界上现有的小麦,
It is estimated that there are about 9.5 billion hectares of salt land in the world. Coupled with the difficulties in agricultural development in some areas, the area of salt land is still increasing. This problem is even more pronounced in those arid and semi-arid countries. Salinity precipitated from surface transpiration, irrigation and high tide are accumulated in the crop rhizosphere. Pakistan accumulates 2.5 tons of salt per hectare of irrigated area every year, so that about 40,000 hectares of land can not be engaged in agricultural production each year with an economic loss of up to 3 billion U.S. dollars. Salty soils can be improved by chemical treatment and drainage, but it is economically indifferent for developing countries to adopt such programs to solve this huge problem. Another approach is to use genetic engineering to cultivate salt-tolerant crop species, and IPSR Crop Breeding Institute selected the world’s most important crop, wheat, for this experiment. Wheat is very sensitive to salt, the world’s existing wheat,