Temporal Variation of Soil Moisture Under Alley Cropping System in Pistachio in Semi-arid Region of Turkey

Alley cropping is practiced to produce grain and forage crops, reduce soil and nutrient losses by surface runoff and improve nutrient availability. Growing barley and legumes for grain and forage in pistachio, olive and vineyards is a common alley cropping system applied in the southeastern Turkey. However, this practice is not being widely used by farmers because of their concern of that these forage crops severely compete the trees for water and nutrients. This study was therefore conducted to observe temporal variation in soil moisture content (SMC) under an alley cropping systems in pistachio to investigate the competition between main and secondary crops for SM in three alley cropping systems and to suggest the most proper alley crops to farmers in the region. The experiment was conducted in an orchard of 20 year-old pistachio trees. There were no differences in SM content among the four treatments from beginning until April 19, 2009. However, the means were significantly different after this date (April 19, 2009). The soil moisture deficit (SMD) calculated was 27.4 mm for control compared to 45.1 mm for alley cropped treatments. Even though there were no significant differences in SMC among the treatments during the whole experimental period, the effect of treatments on the yield or other physiological characteristics of pistachio trees needs investigating for a sound decision on the selection of the best alley cropping system. (C) 2010 Friends Science Publishers