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Suaeda aegyptiaca is a facultative halophyte found in saline and non-saline habitats of the Arab Gulf desert, which produces small-sized undispersible seeds. The interactive effects of maternal salinity and other environmental conditions, such as salinity, light and temperatures, that are prevailing during seed germination have received little attention for a facultative halophyte. This study tested the effects of maternal salinity on salt tolerance during seed germination of S. aegyptiaca under different light and temperature regimes. Seeds collected from both saline and non-saline habitats of the United Arab Emirates ( UAE) were germinated in 0, 50, 100, 200 and 400 mM NaCl, and incubated at 15/25°C, 20/30°C and 25/35°C in both 12-h light/12-h dark regimes and continuous darkness. Generally, seeds of the non-saline habitat were 56% heavier and attained greater germination at the lower temperatures than seeds of the saline habitat. Seeds of the saline habitat germinated better in saline solutions at higher temperatures and in light. Germination was faster for seeds of the saline habitat than for seeds of non-saline habitats. Germination recovery after transfer to distilled water was significantly greater for seeds from the non-saline habitat, compared with seeds from saline habitats. Recovery was greater at lower and/or moderate temperatures, compared with at higher temperatures. Germination was significantly faster during recovery, compared with in the saline solutions. The study indicates that the maternal effect of salinity was confounded with the seed-size effect and it cannot be conclusively confirmed. [ABSTRACT FROM AUTHOR]

The article discusses how sea-water landscaping can help in mitigating sea-level rise due to climate change and in removing carbon from the atmosphere. Topics discussed include possible reduction in cost of landscape landscape irrigation by sea water landscaping in comparison to use of potable water and use of native halophytes as ornament plants in urban landscaping which do not requires pesticides, fertilizers or watering.

• Size, germinability and tolerance of Suaeda fruticosa seeds varied spatially. • Seeds from moist-moderately saline habitat of Manora were largest. • Light requirement for germination was lowest in seeds from high-saline habitat Gaddani. • Germination recovery from salinity was generally higher in seeds from dry habitats. • Recovery from salinity was generally higher than that from dark in all provenances. Information about provenance-based differences in seed attributes of potential cash crop halophytes is limited but important to define sources for the highest quality seeds. This study examined inter- provenance variations in seed morphology, germination, and tolerance responses of Suaeda fruticosa to common abiotic factors. Seed size varied significantly among provenances, and the largest sized seeds were developed in the highly moist moderately-saline coastal area of Manora. Seed germination responses also varied among provenances and seeds from highly moist provenance of Manora showed the highest germination in 400 mM NaCl in light under low to moderate temperature regimes. The light requirement for germination was lowest in the seeds from highly saline provenance of Gaddani. The highest germination recovery of un-germinated seeds from the high salinity (600 mM NaCl) was for seeds from dry provenance of Bahawalpur irrespective of temperature regime. Recovery for seeds from the (moderately) moist (highly) saline provenances of Gaddani and Hawke's Bay was highly temperature-dependent. However, recovery of dark-incubated un-germinated seeds after transfer to light was salinity-dependent, but not dependent on provenance. Thus, these data indicate that provenance can affect the size, germinability, and stress tolerance of S. fruticosa seeds. Generally, seeds from less stressful provenance of Manora had better quality, i.e., larger size, higher germination, and qualify for mass-scale cultivation / restoration programs under most environmental conditions. [ABSTRACT FROM AUTHOR]