The effects of sodium chloride on the aesthetic value of Buxus spp

The use of saline water is an option for the irrigation of salt tolerant ornamentals as competition for high quality water increases. However, despite the importance of ornamental shrubs in Mediterranean areas, salt tolerance of such species has received little attention. Our investigations focused on two species of Buxus L. used in urban green design: B. sempervirens L. and B. microphylla Sieb. & Zucc. 'Faulkner'. Plants were subjected to treatments with two NaCl solutions (125 mM and 250 mM) and distilled water (control), applied by immersion and sprinkler. Injury symptoms by means of visual check were regularly evaluated each two weeks, and SPAD values, and chloride and sodium concentrations were measured in leaves at the end of the experiment. Buxus resulted an interesting genus as no severe damages were detected in all salt-treated plants. With this background, B. microphylla 'Faulkner' resulted less affected by salt stress. B. sempervirens showed more relevant foliar damages (bronzing, yellowing and scorching) and higher chloride and sodium leaf concentration when treated by immersion.