World farm production must rise 60 percent by 2050 to meet the needs of a growing population but this has to happen in “a more sustainable way,” the U.N. food agency FAO and the OECD said on Wednesday. This would mean an extra billion tons of cereals and an extra 200 million tons of meat per year from 2007 levels, the Food and Agriculture Organization and the Organization for Economic Cooperation and Development said in a report. World farm production has grown at an average rate of more than 2.0 percent a year over the past few decades but the rate is expected to slow over the next decade to 1.7 percent a year, the joint report said. The two organizations said growth in production will come mainly from developing countries but would be less vigorous than in recent years. Despite the slowdown, production growth is to exceed expected demographic growth, meaning that farming output per inhabitant will continue to grow by 0.7 percent a year. The calculations do not however take account of growth in the biofuels sector, with experts estimating that world production of bioethanol and biodiesel will nearly double by 2021. The FAO and OECD report also warned however that some 25 percent of farmland in the world was “highly degraded” and said more effort had to be made to encourage sustainable farming and biodiversity.