In 2010, developing countries accounted for 68 percent of global agricultural output
"By 2010, the same high-income and transition economies produced 32 percent of global agricultural output and held 21 percent of world population. Developing countries accounted for 68 percent of global agricultural output, with East, Southeast, and South Asia contributing 44 percent (and comprising 52 percent of world population), and Latin America, Africa, and West Asia contributing the remaining 24 percent of global agricultural output (and comprising 27 percent of world population)."
Keith Fuglie and Alejandro Nin-Pratt. "2012 Food Policy Report", IFPRI, 2012. p.18 http://www.ifpri.org/gfpr/2012/agricultural-productivity [verified 4/15/14]