Abstract

In order to study how diverse cropping system approaches influence grain sorghum productivity, field experiments were conducted in Topeka, KS at the Kansas River Valley Experiment Field; and in Ottawa, KS at the East Central Kansas Experiment Field. The primary objective of this study was to understand how to close yield gaps between the current on-farm yields and the maximum attainable yields. The factors that were tested include narrow row spacing; high and low plant population; balanced nutrition practices, including various timings of nitrogen, phosphorus, and potassium (N-P-K); micronutrient applications of iron and zinc (Fe and Zn); crop protection with fungicide and insecticide applications; plant growth regulator effects; and the use of precision agricultural technology for maximizing yields, including a GreenSeeker meter (Trimble Navigation, Westminster, CO) for more precisely determining N needs for sorghum. Grain sorghum yields ranged from 149 to 166 bu/a in Topeka, KS under irrigation, and from 78 to 100 bu/a in Ottawa, KS, under dryland conditions. At Ottawa, yield potential was limited by precipitation, 10.8 inch. Still, sorghum yield gap between the highest (treatment #2, “kitchen sink” but with low seeding rate) and lowest (treatment #10, “standard practice”) was 22 bushels per acre. The production practices that produced the highest yields varied between the two locations.

Keywords: Sorghum, nutrient uptake, production practices

How to Cite:

McHenry, B., Adee, E., Kimball, J., Prasad, P. V. & Ciampitti, I. A., (2016) “Balanced Nutrition and Crop Production Practices for Closing Sorghum Yield Gaps”, Kansas Agricultural Experiment Station Research Reports 2(5). doi: https://doi.org/10.4148/2378-5977.1219