Dryland Corn Production and Water Use Affected by Tillage and Crop Management Intensity

Management strategies to enhance dryland corn (Zea mays L.) production and soil water use are lacking. We evaluated the effect of tillage and crop management intensity on the growth, yield, and water use of dryland corn from 2005 to 2010 in the northern Great Plains. Tillage systems (no-tillage, NT, and conventional tillage, CT) as main-plot and crop management to corn (traditional intensity: conventional seeding rates and reduced wheat, Triticum aestivum L., stubble height; and improved intensity: increased seeding rate for 3 out of 6 yr and wheat stubble height) as split-plot treatments were arranged in a randomized complete block design with three replications. Corn plant stand was greater for CT than NT in 3 out of 6 yr and greater for the improved than the traditional intensity in 3 out of 3 yr. Seed number and grain yield were greater for NT than CT in 4 out of 6 yr. Biomass was greater for NT than CT in 1 out of 6 yr and greater for NT than CT in the traditional intensity. Corn plant height, seed weight, and harvest index as well as preplant and postharvest soil water, water use, and water-use efficiency were not influenced by treatments, but varied with years. Corn yield increased for NT compared with CT during years with below-average precipitation due to increased seed number and by reducing seeding rate and wheat stubble height. No-tillage with reduced seeding rate and wheat stubble height can enhance dryland corn production without affecting soil water.