With the goal of determining optimal emitter spacing in drip irrigation, experiments were performed to examine the effects of emitter discharge on the wetted perimeter and spacing of emitters. Four types of soils were investigated using emitter discharge of 1.0, 2.0, 3.0 and 4.0 l h −1 . Wetting diameter was measured at six equal time intervals of water application. An equal volume of water was applied. After 1 h of supply of...