Influence of Spring Nitrogen Rate On Wheat In the Northeast Texas Blacklands.

Study was initiated on November 23, 2009 near Howe, TX to evaluate spring nitrogen rate in wheat. Varieties selected were Magnolia, a soft red winter wheat, and hard red winter wheat varieties, Jackpot and Fannin. All plots received 30 lbs nitrogen per acre in the fall. Spring nitrogen rates were 0, 60, 90, 120, and 150 pounds nitrogen per acre. Magnolia and Jackpot were significantly taller than Fannin at harvest across all fertility levels. Magnolia had 17 spikes per spiklets significantly more than Fannin (14) and Jackpot (15). Jackpot had the shortest spike length at 6.5 cm, Fannin and Magnolia spike length was 7.9 cm and 7.6 cm, respectfully, across spring nitrogen rates. Jackpot (68 bu/A) significantly out yielded both Fannin (59 bu/A) and Magnolia (59 bu/A). As long as spring fertilizer was applied there was no difference in plant height at harvest, not applying nitrogen in the spring resulted in 6 to 8% decrease in plant height at harvest across varieties. A similar response was seen in spike length. Regardless of variety, not applying spring nitrogen resulted in at least 19% reduction in yield. Plots were again initiated in the fall of 2010 and will be harvested in June 2011.