The Effects of Nitrogen Environment On Wheat Quality In Diverse Production Systems of Western Washington State.

The purpose of this research is to reduce the input of nitrogen (N) fertilizer in diverse bread wheat production systems in high-rainfall regions without impacting the yield, quality and nutritional value of the baking flour. Wheat is commonly rotated with vegetable, fruit and ornamental cash crops in western Washington in order to reduce nutrient loss, as well as to provide organic matter to the soil, and to break pest cycles. N nutrients are easily lost from farmland by various processes to water as well as the atmosphere, which can pose serious pollution, conservation and health concerns. The potential for this loss is exacerbated with increased precipitation. Understanding how to improve the N efficiency of high-rainfall production systems without severely impacting grain yields, baking quality or the nutritional value of the flour has become tantamount due to a strong and increasing demand for local wheat. The hard red class of wheat, bread wheat, has a unique high N requirement, as baking quality relates to protein content, which in turn relates to N content. Therefore, too little N fertilizer will result in poor yields and poor baking quality, but too much N fertilizer can pose an unnecessary financial burden to farmers and result in harmful environmental impacts if N escapes the farmland. The specific goals of this research are: (1) To evaluate the effect of nitrogen fertilizer (organic versus mineral forms; and 3 different rates of application) on yield, flour extraction rate, baking quality and antioxidant content of 6 different hard red (bread) winter wheat varieties; (2) To evaluate the effect of wheat residues and nitrogen treatments on nitrogen fixation by winter peas grown in rotation with the winter wheat.