FORTY YEARS OF INCREASING COTTON'S WATER PRODUCTIVITY AND WHY THE TREND WILL CONTINUE

Over the last 40 years the amount of irrigation water used by cotton in the United States has decreased-While yields have increased. Factors contributing to higher water productivity and decreased irrigation water use include migration of cotton out of the far western U.S. states to the east where more water requirements are met by rainfall; improved irrigation delivery systems with considerable variation in types and adoption rates across the U.S.; improved irrigation scheduling tools; improved genetics and knowledge of cotton physiology, and improved crop models that can help evaluate new irrigation strategies rapidly and inexpensively. The considerable progress over the last 40 years along with the promise of emerging technologies suggest that this progress will continue.