EFFECT OF WATER STRESS ON THE YIELD OF SOYBEAN AND MAIZE GROWN UNDER DIFFERENT INTERCROPPING PATTERNS

Abstract

Two field experiments were conducted at Giza Agricultural Research Station, Agricultural Research Center, Egypt during 2005 and 2006 growing seasons. The aim of the experiment was to determine the effect of water stress on the yield soybean/maize under different intercropping patterns and their water use efficiency. Intercropping patterns were: 1:1, 1:2, 2:1 and 2:2 soybean/maize. Irrigation treatments consisted of: irrigation using 1.2 pan evaporation coefficient (control), irrigation using 1.0 pan evaporation coefficient (about 7 % reduction in irrigation water than the control) and irrigation using 0.8 pan evaporation coefficient (about 14 % reduction in irrigation water than the control). The yield of soybean and maize under intercropping was changed to units of cereal to simplify the comparison between different intercropping patterns. Water use efficiency values were calculated for the different treatments by dividing yield in cereal units by consumptive water use. Results showed that the highest yield was obtained under 1:2 soybean/maize intercropping pattern and using irrigation with evaporation pan coefficient equaled to 1.2, compared with either