Effect of Sowing Date and Nitrogen Fertilizer Level on the Quality of Wheat Grown in the Eastern Region of Saudi Arabia PDF

Keywords

wheat, nitrogen fertilizer, harvested grains

Abstract

Wheat (Triticum vulgare L.) cultivar Arz was grown under three levels of nitrogen fertilizer and four sowing dates between early November and late December of two growing seasons (82/83 and 83/84). The harvested grains were subjected to quality tests. Kernel weight increased with early sowing, but decreased with the increasing level of nitrogen fertilizer. The Pelshenke test results did not show any consistent effect of treatments but gluten and protein contents increased significantly with increase in fertilizer nitrogen level. The seed hardness test showed softness in the early November sowing, apparently due to rainfall in the first season during the late stages of maturity. This rain also caused black eye wheat and low maximum viscosity, which was detected by the amylograph, indicating minor sprouting and high diastatic activity. A decrease in the pasting temperature of the flour was noticed with an increase in nitrogen fertilizer level. High water absorption of the flour was noticed with the early sowing and higher nitrogen level. The dough developing time showed an increasing trend with increased nitrogen fertilizer, but no effect of sowing date was noticed on the dough development. The dough stability was generally low and inconsistent. Considering all quality parameters it seemed that this variety showed a reasonable response to the increase in nitrogen fertilizer indicating that its quality potential was almost reached under the hot arid conditions of the area. This wheat falls in the range of medium hard wheat. Early sowing improved the quality of wheat, provided that no late rains coincide with the harvest time.