This study aims to evaluate the effect of water stress on growth, nutrients uptake and yield of maize grown under drip irrigation. For this purpose field experiment in a randomized complete block design (RCBD) was carried out at the Agricultural Experimental Station farm of the Faculty of Agriculture, Assiut University, Egypt during the during the summer seasons of 2014 and 2015. Maize plants were irrigated by 100 or 75% of water requirements (I100 and I75).
The obtained results of this study show that the irrigation of maize by I100 significantly (P<0.05) increased the plant growth. Uptake of N, P, and K by maize irrigated by I100 increased by 11, 7 and 16 % in the first season and by 13, 11 and 15% in the second season compared to that irrigated by I75.Increasing the irrigation level to 100% caused a 20 and 6% increase in the straw yield in the first and second season, respectively, also it caused a 20% increase in the biological yield in the first season compared to I75. The grain yield of maize irrigated by I75 was higher by 5 and 10% in the first and second season, respectively, compared to I100. Water use efficiency (WUE) was higher by 41and 56% in the first and second season, respectively, in the case of I75 compared to I100. The data of the current study indicated that water stress caused a slightly reduction in the straw and biological yield of maize, on the other hand it caused a slightly increase in the grain yield.
From this study it recommended maize irrigated by 75% of water requirements was higher of grain yield than that received 100% of water requirements.