Monday, November 5, 2007 - 11:15 AM
53-7

300 Bushel Corn: Is It Possible?.

Roger Elmore, Lori Abendroth, Kendall Lamkey, and Mark Westgate. Iowa State University, Iowa State University, 2104 Agronomy Hall, Ames, IA 50011

The imminent need for more corn drives discussion on corn yield potential.  We must either produce corn on more acres or increase corn yields.  Yields of 300 bu/acre are possible with today's genetics, excellent management, and stress-free environments. Unfortunately, most producers do not have the right combination of these three factors.  Iowa's average corn yield was 166 bu/acre in 2006. These yields are increasing about 2 bu/acre/year. At this pace, Iowa’s state average may reach 300 bu/acre in 6 decades. Environment and management (seeding rate, hybrid selection, among other factors) limit corn yields for average. Yet, many produce 230 to 270 bu/acre by paying close attention to management although management and water may still limit yields of these producers. A different economic situation (allowing unlimited inputs) may allow some top producers to approach or surpass 300 bu/acre. Irrigated National Corn Growers Contest winners have not increased yields over the last 20 years. Contest winners have arrived at a yield ceiling.  Efforts to increase corn stress tolerance have increased yields but not yield potential. Likewise, transgenic hybrids are only protecting yield, not increasing yield potential.  Dramatic changes must occur for the pace of yield gains to continue, and even more change is necessary if the yield gain is to increase. We also recognize that certain forces are at work to actually reduce the annual yield gains. Without major paradigm shifts, 300 bushel per acre yield levels may be achieved in 3 to 6 decades.