Salinity Tolerance of Cacti and Succulents

Abstract

The salinity tolerance of golden barrel cactus (Echinocactus grusonii), ocotillo (Fouquieria splendens), saguaro cactus (Carnegiea gigantea), and Gentry’s agave (Agave parryi truncata) was tested. Plants were irrigated with a solution of EC 0.6, 5.0, 10.0, and 15.0 dS/m. Duration of treatments were 18 weeks for saguaro and 26 weeks for the other three species. In general, fresh weight, dry weight, and moisture content decreased with increasing salinity levels, with the exception of saguaro dry weight which was not affected by the treatments, and ocotillo moisture content which increased with increasing salinity. Runoff was collected three times during the experiment and indicated that ion uptake was higher for barrel cactus than the other three species. EC of runoff averaged for all dates and species showed an increase of 17%, 54%, 46%, and 64% over the salinity treatment solutions of 0.6, 5.0, 10.0, and 15.0 dS/m, respectively.