Author(s)

D. May & B. Hanson

Abstract

Many areas along the west side of the San Joaquin Valley of California are affected by saline soil due to shallow, saline ground water conditions. Artificial subsurface drainage is not an option for addressing the salinity problem because of the lack of drainage water disposal facilities. Thus, the salinity/drainage problem of the valley must be addressed through improved irrigation practices such as converting to drip irrigation. The effect of drip irrigation on processing tomato yield and quality, soil salinity, soil water content, and water table depth was evaluated in four commercial fields located in the San Joaquin Valley of California, USA. Results showed drip irrigation of processing tomatoes to be highly profitable under these conditions compared to sprinkle irrigation. No trend in tomato yield was found with soil salinity levels. While a water balance showed little or no field-wide leaching, soil salinity data clearly showed localized leaching around the drip lines. Keywords: drip irrigation, processing tomatoes, soil salinity, water table, subsurface drip irrigation, leaching, saline, ground water, tomato, salinity. 1 Introduction About 1 million ha of irrigated land are affected by saline, shallow ground water conditions along the west side of the San Joaquin Valley. Upward flow of the shallow groundwater has resulted in excessive levels of root-zone soil salinity. The traditional approach to dealing with shallow ground water problems is to install subsurface drainage systems for water table control and improved leaching, but the proper operation of these drainage systems requires disposal of the subsurface drainage water. No economically, technically, and

Keywords

drip irrigation, processing tomatoes, soil salinity, water table, subsurface drip irrigation, leaching, saline, ground water, tomato, salinity.