Salinity Effects on Emergence, Survival, and Ion Accumulation of Limonium perezii

Abstract

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 × 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), Ca^{2 +}, Mg^{2 +}, 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 Ca^{2 +}, K⁺, and total P decreased, whereas Mg^{2 +}, Na^{2 +}, 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 ∼ 30% more marketable flowers at salinities up to 6 dS m^{− 1}. Thus, Limonium perezii may be produced commercially with moderately saline wastewaters.

Keywords:

• ion accumulation
• salinity stress
• seedling emergence
• seed germination
• statice
• wastewater

ACKNOWLEDGMENTS

We thank Phyllis Nash for providing statistical analyses and Don Layfield for conducting ion analyses. John Draper provided invaluable technical assistance. This investigation was supported financially in part by a CAL-FED grant, administered by the California Department of Water Resources (project manager, Debra Gonzalez). The L. pereziiseeds used in this investigation were purchased from Johnny's Selected Seeds (Albion, ME). Use of company or product names is provided for the convenience of the reader and does not imply endorsement of the product by the United States Department of Agriculture to the exclusion of others that may also be suitable.