Submitted to: Plant and Soil
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 17, 2001
Publication Date: N/A
Interpretive Summary: Reuse of saline subsurface drainage water for irrigation is an option for managing drainage volumes and sustaining crop productivity in California's San Joaquin Valley. Due to high soil salinity, boron, and selenium levels commonly found in these drainage waters produced in central California, identifying crop species that tolerate salt and boron is an on-going selection process. Faba beans is a new plant species recently under consideration for water reuse because it is reported to be boron tolerant and fixes atmospheric nitrogen. Under greenhouse conditions, salt tolerance and boron and selenium accumulation was investigated in faba beans irrigated with poor quality water containing a range of different salinity and boron levels. Results showed that yields of faba beans decreased with increasing salinity levels in the water solution and were less affected with increasing boron levels. Selenium was not translocated in high concentrations to the above-ground organs. Due to faba beans sensitivity to moderate levels of salinity, intermittent use of nonsaline water will be necessary if faba beans are to be irrigated with typical effluent produced in central California.
Technical Abstract: The potential for cyclic reuse of saline drainage water for irrigation has been documented for different crops in central California. Due to the high salinity (Ec = 10 dS/m), B (>10 mg/L), and Se ( > 100 ug/L) levels commonly found in these drainage waters produced in central California, management and disposal of this water has developed into an issue of concern. Growers are considering using faba beans as a cover crop in water reuse strategies, because it is B tolerant and moderately resistant to salinity. Thus, the objective of the greenhouse study was to evaluate the tolerance of faba beans irrigated with typical drainage water and increasing levels of salinity and B. Treatments consisted of salinity levels from 1 dS/m - 10 dS/m, B levels from 10 - 30 mg/L, and one level of Se (250 ug/L). Results showed that total yield was greatest in treatments with a salinity of 1 dS/m and B level less than 30 mg/L, and most severely reduced by the treatment of 10 dS/m and 30 mg B/L. Excessively high concentrations of chloride in plant tissues were statistically shown to be primarily responsible for decreasing dry matter yields. Yields were less affected by the B concentrations used in the saline treatments. Tissue Se concentrations did not exceed 4 mg/kg. Due to faba beans sensitivity to salinity, careful salt management of the soils will be essential for using moderate saline water on faba beans.