The Formula for 300 Bushel Corn
Department of Crop Sciences
Department of Crop Sciences
We developed the Seven Wonders of the Corn Yield World as a tool to teach farmers and agricultural professionals the value of their individual crop management decisions. Given the key prerequisites of weed and pest control and proper soil fertility, the Seven Wonders ranks the top seven factors affecting corn yield each year, and gives each ‘yield wonder’ a relative value expressed in bushels per acre. We used this concept and our understanding of an individual wonders value to develop and evaluate a high technology package of five optimized management practices and inputs, and we compared this to a traditional management system. Yield enhancement from use of a high technology system (combining all five factors) was compared to a traditional technology system (none of the factors), and the value of each individual factor determined using an ‘Omission Plot’ design where each factor is either added one at a time to the traditional-technology system, or removed one at a time from the high technology system.
The five components of the high technology package included: 1) improved soil fertility (i.e. better prerequisites), in the form of a well-placed application of 100 lbs P2O5 as MicroEssentials SZ, even though the soil P test would predict no yield response to fertilizer P; 2) the use of advanced triple or smart-stack hybrids (i.e. herbicide tolerant, corn borer and rootworm resistant); 3) sidedressing an extra 100 lbs of N per acre over the base rate of 180 lbs N/acre as a controlled-release source (we used SuperUrea) to provide a steady supply of ammonium-N during the critical period of yield formation; 4) growing at higher plant populations than standard (45,000 compared to 32,000 plants per acre), especially with twin-rows; and, 5) applying a strobilurin foliar fungicide at flowering (Headline or Quilt) to control leaf disease and to relieve plant stress.
Replicated trials were conducted in DeKalb, Champaign, and Dixon Springs in 2009 using the Omission Plot design. There was a marked visual difference in plant appearance between the traditional and high-technology plots during late grain fill (see picture), which was associated with higher yield for the high-technology plots at all sites (range of 14 to 66 bushels/acre). Although the relative importance of the five high-technology factors varied for the different sites, in all cases the value of a given factor when combined with the other factors in the high-technology package was substantially greater when that factor was provided alone. These trials show that single production factors cannot guarantee high corn yields, but rather it is the positive interaction among multiple factors that gives farmers the greatest opportunity to grow 300 bushels/acre.
Differences in plant appearance between the high technology and standard technology
plots during the later stages of grain filling at Champaign, IL in 2009. Picture was taken
on September 17 at the late R5 growth stage.