Kent McKay, Area Extension Agronomist/Cropping Systems, NCREC
Kristie Michels, Research Specialist, NCREC
Brad Miller, Research Agronomist, Dakota Growers Pasta Company, Carrington, ND
Pat Carpentier, NDSU McLean County Extension Agent Sakakawea MEY Club

Trial Information:
The objective of this trial was to evaluate seeding rate, nitrogen application timing, and fungicide application for Fusarium head blight control in durum wheat. The trial was conducted on the Dave Schlichting farm 5 miles west of Garrison in 2003. 'Lebsock' durum was planted May 21 on previous sunflower ground. The soil tested 31 pounds of nitrogen in the top two feet. A yield goal of 50 bushels per acre was set, resulting in an additional 90 pounds of actual nitrogen per acre to be applied. Seeding rates of 1.0 million pure live seed (88lbs/A) and 1.5 million pure live seed (132 lbs/A) were used. Fertility treatments are described below. Folicur was applied to the fungicide treatments on July 15 when the durum was 100% headed (Feekes 10.5). Fusarium head blight and leaf disease were rated August 8. Plots were harvested with a plot combine on August 21.

Fertility Treatments:
1. 90 lbs of actual nitrogen per acre was applied and incorporated prior to planting on May 21.

2. 45 lbs of actual nitrogen per acre was applied and incorporated prior to planting on May 21. An additional 45 lbs of actual nitrogen was applied at the 2 leaf stage on June 12 with a CO2 pressurized sprayer, equipped with TeeJet-StreamJet nozzles delivering 15 gallons of 28-0-0.

3. 90 lbs of actual nitrogen per acre was applied at the 2 leaf stage on June 12 with a CO2 pressurized sprayer, equipped with TeeJet-StreamJet nozzles delivering 30 gallons of 28-0-0.

4. 90 lbs of actual nitrogen per acre was applied at the jointing (4 1/2 leaf) stage on June 23 with a CO2 pressurized sprayer, equipped with TeeJet-StreamJet nozzles delivering 30 gallons of 28-0-0.

Results:
May was cool with above normal precipitation. Top soil and planting conditions were excellent on May 21. June was cooler than normal with above normal precipitation. There was significant precipitation within 48 hours from when the liquid nitrogen treatments were applied on June 12 and June 23. July was significantly warmer and drier than normal. This resulted in unfavorable conditions for Fusarium head blight (FHB) to develop. Durum samples from each plot were sent to the NDSU Toxicology Lab for DON evaluation. All samples had below 0.5 ppm DON.

There were no significant differences in yield with the preplant nitrogen treatments, the split nitrogen treatments or the 2 leaf foliar nitrogen treatments (Table 1). The jointing foliar nitrogen treatments, except the 1.5 M PLS Folicur treatment, had significantly lower yields and test weight compared to the other fertility treatments. The Folicur treatments significantly reduced flag leaf disease and FHB severity; however, disease levels were so low they did not have any impact on yield or test weight. In summary, the 90 lbs of nitrogen PPI treatments had the highest net return on average compared to the other fertility treatments (Table 3).