The objectives of the study were to test the effect of two methods of applying nitrogen fertilizer (fertigation and broadcasting), two irrigation levels and two irrigation systems surface and subsurface drip on summer squash production in the sandy soils The main results of the study could be summarized as follow:-• Applying the nitrogen fertilizers through two irrigation methods (surface and subsurface drip irrigation) was more efficiency than broadcasting fertilizers. • There are a slightly increase in crop growth, fresh yield, and both of water and nitrogen use efficiency in subsurface drip more than in surface drip. • Subsurface drip irrigation has the best water distribution in the soil. • The highest value of fertilizer use efficiency (35.60 kg) yield/kg nitrogen was obtained with treatment I2L2F2.

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