The present investigation was carried out at Sakha Agricultural
Research Station. Kafr E1-Sheikh Governorate Minstry of Agriculture during the
three growing successive seasons (1988. 1989 and 1990 seasons) to study the
effect of soil moisture levels, foliar application of ،inc sulphate and maize
varieties on the water relation of maize plant i.e. water consumptive use. water
uptake. water use efficiency and the crop coefficient (kc). The main result could
be summarized as follows:
1- Seasonal consumptive use amounts increased as the availability of
soil moisture increased in the root zone. Soil moisture stress induced a reduction
in the consumptive use. Maize cultivars and zinc levels had no obvious effect on
water consumptive use. The daily consumptive use increased gradually as plant
growth increased and reached its maximum at about silking and seed formation
2- The relation between consumptive use in cm (x) and maize grain
yield in kg/feddan (y) for all moisture treatments was linear. The grain yield of
maize increased 65.24 kg/fed. by increasing one unit (cm) of seasonal
consumptive use of maize. The correlation coefficient for the two variables was
significantly positive and equal 0.999.
3- Maize plants extracted about 83 13% of its water needs from the
4- The highest water use efficiency value (1.40 kg/rn3 of water
consumed) was recorded when maize plants were irrigated at 40% depletion in
available water. Water efficiency of T.W.C 3 l cultivar was higher than the
other cultivars. The highest water use efficiency was obtained by applying zinc
sulphate at 0.3%
5- The average values of seasonal crop coefficient (kc) of maize for the
three growing seasons were 0.88. 0.89. 1.07 and 1.12 for Penman. Radiation.
modified Blaney-Criddle and the class A pan methods, respectively.
6- It could be concluded that the calculated value of 0.88 for (kc) could
be used in calculating the consumptive use of maize in North Delta area as
estimated by the aid of Penman or Radiation methods.