Furrow and Trickle Irrigation: Effects On Soil Oxygen and Ethylene and Tomato Yield

Abstract
This study was conducted to determine whether low soil oxygen levels or high soil ethylene reduce tomato (Lycopersicon esculentum) yield in clay soil, when high temperatures are combined with trickle or furrow irrigation. Treatments were daily or weekly trickle irrigations (100 or 120% of pan evaporation) and furrow irrigations (5‐ or 10‐d intervals). Soil oxygen and ethylene levels and soil matric potentials were measured at the 20‐ and 40‐cm depths immediately before and during part of the fruiting cycle. Daily trickle irrigations (100 or 120% of pan evaporation) resulted in oxygen levels of 3 to 6% and matric potentials of 0 to −7 kPa. Furrow irrigation or weekly trickle irrigations resulted in oxygen levels that were about double the values measured for the daily trickle irrigation, and in soil matric potentials of −1 to −60 kPa. Irrigation frequency or rate did not have a significant effect on yield of tomatoes. Soil ethylene levels were low for all treatments (< 1 ppm). Because of higher oxygen level, weekly trickle or furrow irrigation would be preferable to daily trickle irrigation when oxygen may be limiting or when the crop grown is oxygen sensitive.