SALT TOLERANCE AND SALT ACCUMULATION OF LANDSCAPE PLANTS IRRIGATED BY SPRINKLER AND DRIP IRRIGATION SYSTEMS

Field trials were conducted to evaluate salt tolerance of landscape plants for recycled-water irrigation. Ten selected landscape plant species exhibited substantial differences in salt tolerance. Plants with more tolerance to salt tend to accumulate less salt than less salt tolerant plants. Plants were more susceptible to salt stress under sprinkler irrigation than under drip irrigation, because leaf direct contact with salt. No apparent salt stress symptom was detected when plants were irrigated by drip irrigation either with 500 mg L^?1 or 1500 mg L^?1 salt (NaCl). Therefore, drip irrigation using recycled water may be accept-able for many landscape plants in California landscape. There was a positive relationship between the salt tolerance revealed by sprinkler irrigation and the salt tolerance revealed by drip irrigation. This positive relationship is a potentially useful character to screen for salt tolerant landscape plants. Selection for salt tolerant landscape plants for recycled water irrigation is a viable approach for landscape management.