Water was applied to each block weekly to simulate the average amount of precipitation for that week. One block was treated with normal amounts of precipitation, a second block at 1.25 of normal, and the third block at 0.75 of normal to simulate excess and water deficit conditions, respectively. Visual observations were made of plant growth during the season and in one chamber the air temperatures were increased by 5 °C for one week at the V6, V12, and pollination stage. The chamber with the high temperature exposures then had minimum temperatures increased by 3 °C for the period from the end of pollen shed until maturity of the crop. Numbers of leaves, leaf length and maximum leaf width were measured throughout the growing season to determine phenological development and leaf area. At maturity, each plant was harvested from the soil block and the vegetative biomass and grain amounts determined for each plant and then averaged for the block to determine the production.