You've hit on one of my favorite topics, as well as a man who redefines the word "hero", yet practically nobody knows him:
(Norman) Borlaug is an eighty-two-year-old plant breeder who for most of the past five decades has lived in developing nations, teaching the techniques of high-yield agriculture. He received the Nobel in 1970, primarily for his work in reversing the food shortages that haunted India and Pakistan in the 1960s. Perhaps more than anyone else, Borlaug is responsible for the fact that throughout the postwar era, except in sub-Saharan Africa, global food production has expanded faster than the human population, averting the mass starvations that were widely predicted -- for example, in the 1967 best seller Famine -- 1975! The form of agriculture that Borlaug preaches may have prevented a billion deaths.