Alternate furrow irrigation with proper irrigation intervals could save irrigation water and result in high grain yield with
low irrigation costs in arid areas. Two field experiments were conducted in the Middle Nile Delta area of Egypt during the
2010 and 2011 seasons to investigate the impact of alternate furrow irrigation with 7-d (AFI
7) and 14-d intervals (AFI
14) on
yield, crop water use efficiency, irrigation water productivity, and economic return of corn (
Zea mays
L.) as compared with
every-furrow irrigation (EFI, conventional method with 14-d interval). Results indicated that grain yield increased under
the AFI
7 treatment, whereas it tended to decrease under AFI
14 as compared with EFI. Irrigation water saving in the AFI
7
and AFI
14 treatments was approximately 7% and 17%, respectively, as compared to the EFI treatment. The AFI
14 and AFI
7
treatments improved both crop water use efficiency and irrigation water productivity as compared with EFI. Results also
indicated that the AFI
7 treatment did not only increase grain yield, but also increased the benefit-cost ratio, net return, and
irrigation water saving. Therefore, if low cost water is available and excess water delivery to the field does not require any
additional expense, then the AFI
7 treatment will essentially be the best choice under the study area conditions.