Nitrogen Rate Effect on Lodging in Wheat

Rationale and Objective

  • Previous research has shown that wheat yield can increase with nitrogen (N) fertilizer rate up until the point that lodging occurs, which reduces yield.
  • Field trials were conducted in Illinois to observe the effect of N fertilizer rates on lodging in several Pioneer® brand wheat varieties.

Study Description

Locations: 4 along the I-64 corridor in southern Illinois 
Factors: Nitrogen rate, Pioneer® wheat varieties 
    •  Nitrogen Rates (lbs/acre):
       70, 90, 110, 130, and 150 
    •  Pioneer® Varieties:
       25R78          25R77         25R62
       25R46          25R40         25R32

Study Details

  • Plots were planted after soybeans to minimize effect of carryover N from a previous corn crop.
  • Varying amounts of N were applied at Feekes growth stage 6 (jointing).
  • Wheat lodging was visually estimated. Results shown below represent an average across 4 trial locations.


  • The spring of 2013 was abnormally wet in southern Illinois, with rainfall in April totaling 6 to 8 inches above normal.
  • At the 70, 90 and 110 lb/acre N rates, all varieties stood very well, and no lodging was observed.
  • At the 130 lb/acre N rate, no lodging occurred in any varieties except Pioneer® variety 25R32. Approximately 10-15% lodging was observed in 25R32 at this N rate.
  • At the 150 lb/acre N rate, 25R78, 25R62, 25R77 and 25R40 had no lodging. 25R46 was lodged at the 10% range and 25R32 was lodged at the 25-30% range.
  • N availability can be heavily influenced by the weather. In a spring with less rainfall, these results, especially the exact rates, could and would likely change. However, the variety response would be expected to be the same, relative to each other.

Lodging (%) observed in wheat varieties as affected by N rate.

  Nitrogen Rate (lbs/acre)
Variety 70 90 110 130 150
  -------------- lodging (%) ---------------
25R78 0 0 0 0 0
25R77 0 0 0 0 0
25R62 0 0 0 0 0
25R46 0 0 0 0 10
25R40 0 0 0 0 0
25R32 0 0 0 10-15 25-30

2013 data are based on average of all comparisons made in 4 locations through November 15, 2013. Multi-year and multi-location is a better predictor of future performance. Do not use these or any other data from a limited number of trials as a significant factor in product selection. Product responses are variable and subject to a variety of environmental, disease, and pest pressures.  Individual results may vary.