IMPROVING WATER AND N-USE UTILIZATION FOR FIELD CROPS VIA LTERNATE- FURROW IRRIGATION ECHNIQUE. 1-MAIZE CROP

Two field experiments were executed at the farm of Gemmeiza Agric. Res. Stn. during 2001and 200 seasons, to find out the extent to which alternate-furrow irrigation  technique, affected water and N-utilization for maize crop.
         Data revealed significant reductions in applied water, due to conveying the water through alternate- furrow irrigation at,  7 or  14 days interval. Increasing N-rate resulted in increased applied water values, under the adopted irrigation techniques , a similar trend was observed regardless irrigation techniques as well.
          Alternate-furrow irrigation , at 14 days interval, seems to decrease the grain yield insignificantly, whereas, under alternate –furrow at 7 days interval, the figure was increased by 14,5%, as compared with every-furrow irrigation. Increasing N-rate gradually increased grain yield value, and this was true under the adopted irrigation techniques , regardless the irrigation effect too.
           Water Use Efficiency(WUE) values were improved under alternate-furrow irrigation, either 7 or 14 days interval, comparable to every-furrow irrigation. Increasing N-rate resulted in increased WUE values, either regarding or regardless irrigation techniques. Nitrogen Use Efficiency(NUE) seems to decrease with alternate-furrow irrigation at 14 days interval, while the corresponding value with alternate-furrow irrigation at 7 days interval was increased, compared with every-furrow irrigation. Moreover, NUE was decreased as N-rate increased, this was true under the adopted irrigation techniques ,also regardless them.
          Total grain-N%, grain N-uptake, grain N-recovery % and residual soil inorganic-N values, seemed to decrease under alternate-furrow irrigation at 14 days interval, compared to both alternate-furrow with 7 days interval, and every-furrow irrigation techniques. This may be due to less N- availability under the more drier conditions prevailing  under such irrigation technique.