Salinity effects on emergence, survival, and ion accumulation of Limonium perezii

Saline wastewaters may provide a valuable water source for the irrigation of selected salt-tolerant floriculture crops as water quality and quantity becomes limited and as demand for quality water increases. A 2 x 7 factorial design with three replications was used to test the effects of water ionic composition and salinity, respectively, on emergence, survival, and mineral accumulation of the salt-tolerant cut flower Limonium perezii (Stapf) F. T. Hubb cv. 'Blue Seas.' Seeds (n = 100) were sown in each of 42 presalinized greenhouse sand tanks. Irrigation water composition represented saline drainage waters typically present in either the San Joaquin Valley (SJV) or the Imperial/Coachella Valleys (ICV) of California. Electrical conductivity levels of the treatment waters were 2.5 (control), 6, 8, 10, 12, 16, and 20 dS m(-1), respectively. Seedling emergence was monitored daily and leaf mineral concentrations (total sulfur (S), total phosphorus (P), Ca2+, Mg2+, Na+, K+, and Cl-) were determined three months after planting. A two-way ANOVA revealed that salinity had a significant effect on seedling emergence (F = 27.56; P < 0.01). Cumulative emergence showed a marked decrease above 12 dS m(-1) for both water treatments and tended to be greater from 6-10 dS m(-1) than at 2.5 dS m(-1). A significant interaction of salinity and water composition was found for survival (F = 2.90; P < 0.05). Survival approximated 90% in ICV and SJV treatments up to 8 and 10 dS m(-1), respectively, yet continued to decrease below 70% in both water treatments at 12 dS m(-1) and higher. Differences in leaf-mineral concentrations between ICV and SJV water composition can be attributed to differences in composition of irrigation waters. As salinity increased, leaf Ca2+, K+, and total P decreased, whereas Mg2+, Na2+, Cl-, and total S increased. Stem length showed a marked decrease above 2.5 and 6 dS m(-1) under ICV and SJV treatments, respectively, with SJV waters producing similar to 30% more marketable flowers at salinities up to 6 dS m(-1). Thus, Limonium perezii maybe produced commercially with moderately saline wastewaters.