Reprint of The impact of new grain varieties in Asia, by J. W. Willett, first published 1969, by U.S. Dept. of Agriculture, Economic Research Service, Foreign Regional Analysis Division, Washington; of High-yielding varieties of wheat in developing countries, by S. K. Tsu, first published 1971, by Dept. of Agriculture, Economic Research Service, Washington; of Accelerating India's food grain production, 1967-68 to 1970-71: requirements and prospects for a yearly growth rate of 5 percent, by W. E. Hendrix, J. J. Naive, and W. E. Adams, first published 1968, by U.S. Dept. of Agriculture, Economic Research Service, Washington; and of Technological change in agriculture: effects and implications for the developing nations, by D. G. Dalrymple, first published 1969, by Foreign Agricultural Service, U.S. Dept. of Agriculture, Washington.

Includes bibliographies.