Effect of Spacing and N Levels On Yield and Quality of Sweet Corn Grown Under Minimal Tillage.

Sweet corn grown in California, USA is mostly planted using conventional tillage methods which involves extensive disking and preparation of the seed bed for planting. In recent years, conservation tillage practices including minimal and zero tillage have been tried in silage corn in California but its adoption in sweet corn is minimal. At California State University, Fresno, we plant approximately 70 acres of sweet corn. Since 2006, we switched to minimal tillage practices for growing sweet corn using permanent beds spaced 60” apart.  Sub-surface drip system was followed with drip tapes buried under the surface at 4” depth.  The objective of this study was to determine optimum spacing and nitrogen levels for yellow sweet corn under minimal tillage conditions using fertigation methods.  Three spacing treatments of 28,000, 31,000, 34,000 plants per acre and three nitrogen levels of 100, 150, and 200 units of Nitrogen were tested in three replications using split-plot design for three years in 2007, 2008 and 2009.  Honey Select, a super sweet corn hybrid was used for the study.  Yield and yield components were measured for harvestable ears.  Results from four seasons of trials will be summarized and discussed