Water use efficiency of Maize (Zea mays) grown on a calcareous soil under drip irrigation system [electronic resource]

Includes bibliographic reference

A field experiment was conducted at the experimental farm of Nubaria Horticulture Research Station, Agriculture Research Center to quantify the response of maize grown on calcareous soil to three different water regimes: 100%, 75% and 50% of the Etc (symboled (I1), (I2) and (I3)), and different applications of K and N fertilizers with regards to enhance the water use efficiency (WUE). Three potassium rates (Ko= Zero, K24 = 24 andK48 = 48 kg K2O/fed as potassium sulfate,48% K02) and two nitrogenrates (N90=90and N120=120kgN/fedas Urea,46%N) were used. The experiment was conducted over two growing seasons (2005 and 2006). The average values of cumulative consumptive use (CU) at development, mid-season and late season stages for I1, 12 and I3 were calculated as 375.5, 307.0, and 221.5 mm, respectively. The highest values of CU were obtained with K48 and N120 treatments. The K48 presented the highest value of WUE in the 1st season, while no significant differences were observed between K24 and K48 in 2nd season. The N 120 dose significantly increased WUE by 13.5% and 19.7 % than the N90 dose in 1stand 2nd seasons, respectively. The interaction between irrigation regimes and potassium levels significantly affected WUE. The I3 presented the highest value of irrigation water use efficiency (IWUE) were 1.511 and 1.621 kg/m3, followed by I2 (1.325 and 1.389 kg/m\ whereas I1 presented the least value (1.lll and 1.2 kg/m3) in 1st and 2nd season, respectively.K48 presented the highest value of IWUE (1.562 and 1.513 kg/m3 followed by K24 (1.285 and 1.418 kg/m3 whereas K0 presented the least value (1.1 and 1.282 kg/m3) in 151 and 2nd season, respectively. The N120 significantly increased IWUE by 17.9 and 24 % than N90 dose in 1stand 2nd season, respectively. The interaction between irrigation regimes and potassium •levels significantly affected IWUE. A significant effect was observed as a result of the interaction between irrigation regimes and potassium levels on grain yield of maize in the two growing seasons. The irrigation scheduling of I3, and I2 saves 23%, and 46 % of applied irrigation water compared to treatment I1 during the two seasons, respectively.

Summary in Arabic