TheAhmed Moursy^*(1) and Mazen Ismail⁽¹⁾(1). Soil   and   Water Research Department, Nuclear   Research   Center, Atomic   Energy   Authority, Abou-Zaabl, Egypt.(*Corresponding author: Ahmed Moursy. E-mail address ahmad1a2m3@yahoo.com).Received: 07/04/2019                                Accepted: 11/05/2019AbstractAn experiment was conducted at the Soils and Water Research Department, Nuclear Research Center, Atomic Energy Authority, Egypt, in the year 2018, to study the effect of gamma radiation at different doses (zero, 40, 80 and 160 Gy) on growth and yield of wheat fertilized with 0.0, 120 and 240 N kg ha^-1 as urea fertilizer. The experiment was laid out in randomized complete block design with three replicates. Results revealed that, straw and grains yields were significantly fluctuated between the increase and decrease, furthermore, under 80 Gy gamma rays, the highest value was 15.677 kg plot^-1, observed at rate of 240 N kg ha^-1 in addition to 80 Gy. Grains increased compared to all treatments and control. Under gamma rays, the highest values of straw and grains were 9.974 kg plot^-1 and 15.677 kg plot^-1 observed rate of 240 kg ha^-1 plus dose of 40 and 80 Gy radiation respectively. The data indicated that, N uptake by straw and grains, in non-irradiated treatments, were significantly increased with increasing the doses of nitrogen fertilizer levels 100 kg N fed^-1 and gamma rays dose up to 80 Gy. Furthermore, the highest N uptake of 98.3 g plot^-1 and 181.1 g plot^-1 were observed at rate of 240 kg N ha^-1 in addition to zero Gy, compared to control, whereas, under doses 80 Gy the highest values of N uptake were 120.1 g plot^-1 and 195 g plot^-1 which recorded with straw weight and grains yield, respectively.The Effect of Gamma Rays and Different levels of Nitrogen Fertilizer on the Productivity of Wheat (Triricum aestivum L.)