Biotechnological Contributions to Food Secrurity with Cassava and Rice

抄録

Present world food production would provide ca. 2, 400kcal/day/person if it could be equally distributed amongst the world population. Food is, however, and will always be, unevenly distributed. Many of us are used to consume 3, 400kcal/day. However, 800 million are starving at 1, 800kcal/day, and 3.4 billion live at the minimal level of 2, 200kcal/day. Although food security to date may be mainly a poverty problem, it is increasingly becoming a production problem. The world population is growing by 90 million p.a. and will, probably, stabilise only when a total of 10-12 billion has been reached. At the same time, however, world-wide food production per capita is declining, as is the crop land and the water available for agricultural food production. The continuous increases in food productivity of the past decades are declining and two of the three major food systems—oceans and rangelands—are already exploited at their limits. The world population will continue to grow dramatically and most of this population growth will occur in Developing Countries, which will not be rich enough to compete on the world market for food surplus and which, therefore, will, have to increase their harvests from agricultural land dramatically. And this increase has to be achieved under sustained conditions, with reduced inputs in agrochemicals, energy, water and manpower. Yield per acre has at least to be doubled. The most direct approach to an increase in food production, without an additional increase in input of resources, would be via reduction of losses with the help of resistant crop varieties. As crop loss is still in the range of 50% for the major food security crops such as rice and cassava, the potential of such an approach is enormous. Genetic engineering could, therefore, substantially contribute to the rescue of lost harvests via production of resistant varieties. It also could contribute to a second facet of food security, the improvement of food quality with regard to vitamins, micronutrients and essential amino acids. From our work at the ETH Zürich we will present the state of the art of projects with the food-security crops rice and cassava on pest- and disease resistance, supply of provitamin A, iron and protein, and reduction of toxic compounds.