Dryland Corn and Grain Sorghum Response to Different Levels of Available Soil Water at Planting.

Field studies were conducted at the Kansas State University-Southwest Research-Extension Center near Tribune, KS and the KSU-Northwest Research-Extension Center near Colby, KS from 2012 to 2014.  Four levels of available soil water at planting were established by applying 0, 38, 76, and 114 mm of irrigation from a linear-move sprinkler approximately one month prior to planting.  The crops were then grown without supplemental irrigation.  The objective was to determine the effect of different levels of plant available soil water at planting on grain yield and water productivity of dryland corn and grain sorghum. Water productivity tended to increase with increased available soil water for corn but not for grain sorghum. Grain yield response to initial plant available soil water varied greatly with crop, location, and year. Grain yield response to increased soil water at planting was more consistent and greater for corn than grain sorghum.