EFFECT OF SENSOR-BASED HIGH FREQUENCY IRRIGATION ON BELL PEPPER YIELD AND WATER USE

Abstract

Three levels of sensor based high frequency irrigation treatments and four levels of twice daily irrigation treatments were applied to bell pepper (Capsicum annuum L.) in 2002 to test the effect on yield and seasonal irrigation volume, water use efficiency, and soil moisture content in the root zone. Sensor based treatments used a soil moisture sensor buried 10 cm deep within the crop root zone to maintain soil moisture at a set level. The two sensor based irrigation treatments with the largest seasonal irrigation volume resulted in yields similar to the two largest seasonal volume daily irrigation treatments (marketable yields ranged between 17,000 and 20,000 kg/ha for these treatments), but used approximately 50 % less seasonal irrigation water. This resulted in irrigation water use efficiencies of 1209-2316 kg/ha/m3 for the sensor based treatments while those of daily treatments ranged from 703 to 1612 kg/ha/m3. Sensor based irrigation treatments resulted in significantly higher soil volumetric moisture levels at the 15 and 30 cm depths. The results indicate that high frequency irrigation events based on soil moisture sensor control can maintain crop yields while reducing irrigation water requirements; however, future research is needed to reproduce this first year of results.