SHRINKING WHEAT: The development of short-statured wheat began with a semidwarf variety called Norin 10. Norman Borlaug bred Norin 10 with multiple other varieties to select for those that had both strong, stocky stems and good agronomic features. This photo shows the widely varying progeny of a cross between Chapingo 53, a tall variety of wheat that was resistant to a fungal pathogen called stem rust, and a variety developed from previous crosses of Norin 10 with four other wheat strains.CMMYTAs an Iowa farm boy who lived through the Great Depression, Norman Borlaug viscerally understood the toll of poverty and hunger. It fueled his determination to feed a global population that was increasing exponentially—and his tenacious belief that the way to do so was by boosting crop yields.
Trained as a plant pathologist, Borlaug joined the Rockefeller Institute–funded Cooperative Wheat Research and Production Program in Mexico (a precursor to CIMMYT, the International Maize and Wheat Improvement Center) in 1944 to develop varieties resistant to a fungal pathogen called wheat rust. (See “Putting Up Resistance,” page 34.) He succeeded, but the tall varieties he worked with tended to fall over, or “lodge,” in the wind or rain when the seed heads grew large. In 1953, Borlaug obtained a Japanese variety of semidwarf wheat called Norin 10, which was two feet shorter. He first bred Norin 10 with local rust–resistant Mexican strains, and eventually crossed the hybrids with wheat varieties from other countries. This painstaking work continued for years, but yielded wheat with plump heads ...
