Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: May 6, 2005
Publication Date: October 28, 2005
Citation: Nielsen, D.C., Vigil, M.F., Benjamin, J.G. 2005. The variable response of dryland corn yield to soil water at planting. Agronomy Abstracts. Presented at the 2005 ASA, CSSA-SSSA International Annual Meeting. Nov. 6-10, 2005. Salt Lake City, UT. Technical Abstract: Farmers in the central Great Plains would like to diversify crop rotations from the monoculture of the traditional winter wheat-fallow system. Corn could work well as a rotation crop, but inputs are expensive and farmers would like to know the chances of producing a certain yield before investing in seed, fertilizer, herbicides, etc. Information on the yield response of corn to available soil water at planting could help guide the crop choice decision regarding corn. This study was conducted to determine if a predictive relationship exists between dryland corn yield and available soil water at planting time. Yield and soil water data from 10 years of an alternative crop rotation study at Akron, CO were analyzed by linear regression to determine predictive relationships. The yield-water content production function was found to be highly variable, ranging from 98.8 to 671.6 kg/ha per cm of available soil water in the 0-180 cm soil profile at planting. The differences in yield response to soil water were related to the amount and timing of precipitation that fell during the corn growing season. Because dryland corn yield is greatly dependent on rainfall during reproductive and grain-filling stages, soil water content at corn planting cannot be used to reliably determine whether corn should be planted in a flexible rotational system.