Wheat growth and nitrogen use efficiency under drip irrigation on semi-arid region

Abstract

Irrigation water is limiting factor for crop production in arid and semi-arid regions. Modern irrigation system such as drip irrigation are widely used in Egypt and also used in other countries especially have limited irrigation water resources. Drip irrigation provides the efficient use of limited water resources with increasing water productivity (WP). Application of nitrogen to wheat is needed to ensure the N availability throughout the growing season due to its important role in promoting both vegetative and reproductive growth. A field experiment was carried out during growing season of 2017/2018 at a private farm located at a newly reclaimed sandy soil at El-Sadat district El-Menofiya governorate , Egypt to study the effect of two nitrogen fertilizer types (ordinary and slow release N fertilizers) as urea 46.5%N and urea formaldehyde (38%N) with four application rates i.e., 0, 40, 60 and 100 kg N fed -1 (1 feddan=4200 m 2 ) combined with drip irrigation moisture depletion from filed capacity (FC) (I1=100% of FC) and (I2=50% of FC) on wheat crop. The results showed that application of water depletion at (I1) through drip irrigation along with 100 kg N fed -1 , from two sources of nitrogen recorded the highest yield of straw and grain and the nitrogen content as well as nitrogen use efficiency compared with the other rate and levels of nitrogen and irrigation, respectively. Also, water productivity increased with irrigation I1 FC and nitrogen levels and reached the highest values at 100 kg N fed -1 as fertigated urea compared with urea formaldehyde as slow release fertilizer.