Physiological and Yield Response of Green Bell Pepper to Soil Moisture Sensor Controlled Drip Irrigation

The objectives of this study were to evaluate the physiological and yield response of pepper to different soil moisture thresholds using soil-moisture-sensor (SMS) irrigation control. Irrigation treatments were set at specific threshold of volumetric-water-content (VWC) which was allotted five irrigation windows/day and bypassed events if the VWC exceeded the established threshold. Treatments were: threshold of 4, 8, 12%VWC single irrigation-drip at center of the bed (SS); threshold of 8, 12%VWC with double drip-irrigation (SD); TIME_2h with fixed 2hr irrigation/day and TIME_{4 x 24} with 4 fixed events of 30min/day. The use of SMS reduced irrigation water applied (81; 118; 138; 112; 201; 341 and 260mm for SS₄; SS₈; SS₁₂; SD₈; SD₁₀; TIME_2h and TIME_{4 x 24}, respectively). For the same order, the pepper yield was 26; 31; 35; 30; 42; 33; 41 Mg/ha. Water and NO₃—N captured in lysimeters were lower on SMS irrigation controlled compared to TIME based irrigation commonly used by producers.