Water Stress: A Challenge for the Future of Agriculture

摘要: When analyzing the progress of agriculture in recent years we find a boom farm yields after World War II until about 1970. This is mainly attributed to massive inputs energy by means fertilizers, pesticides, irrigation, and mechanization, as well genetic improvement crops. The per unit area, however, have not increased since 1970 and, accordingly, any overall increase crop production during this period was achieved cropping more land. In fact, land brought under cultivation arid semiarid regions large irrigation projects. No doubt there still potential for further expansion irrigated Assuming that all current planned development projects will be achieved, Jewitt (1966) estimates end century world’s area very likely expand an additional 40 million total 200 hectares. However, despite these perspectives, it important consider itself no equivalent intensive productive agriculture, failure many suggests (Arnon, 1972). vast capital investments together with continuously increasing costs make success such plans ambiguous. It appears, therefore, change priorities agricultural research necessary. Future has point study factors which limit ways enabling plants utilize effectively available environmental resources. According joint report National Research Council Academy Sciences United States, targets near future must include methods improving photosynthetic efficiency, biological nitrogen fixation, nutrient water use resistance stresses (Wittwer, 1978). Obviously, crops work than present ones order meet demands food fiber.