Effect of irrigation frequency on subsurface drip irrigated vegetables

Abstract

The effect on crop yield of drip-irrigation frequencies of two irrigations per day (2/d), one irrigation per day (1/d), two irrigations per week (2/week), and one irrigation per week (1/week) was investigated for lettuce (Lactuca sativa), pepper (Capsicum annuum), and onion (Allium cepa) grown on sandy loam and processing tomato (Lycopersicon esculentum) grown on silt loam during experiments conducted during 1994 to 1997. All treatments of a particular crop received the same amount of irrigation water per week. Results showed that the 1/week frequency should be avoided for the shallow rooted crops in sandy soil. Irrigation frequency had little effect on yield of tomato, a relatively deep-rooted crop. These results suggest that drip irrigation frequencies of 1/d or 2/week are appropriate in medium to fine texture soils for the soil and climate of the project site. There was no yield benefit of multiple irrigations per day.