Salinity, temperature and light affect seed germination of Haloxylon salicornicum, a common perennial shrub of the Arabian deserts

Summary Haloxylon salicornicum (Moq.) Bunge ex Boiss. has been considered as one of the most promising species for re-seeding deteriorating desert range vegetation, and for sand dune fixation in the Arabian deserts. However, plant communities dominated by this species have become seriously degraded due to overgrazing. Reseeding degraded communities with this species requires information about light and temperature requirements and salinity tolerance at different temperatures of its seed germination. Seeds were germinated in saline concentrations (up to 800 mM NaCl) in incubators adjusted to 15, 20, 25 and 30°C, in both continuous light and dark. In non-saline treated seeds, germination in light conditions was similar for temperatures up to 25°C, but declined significantly at 30°C. Germination in darkness at either 15 or 20°C was significantly greater than at 25 and 30°C. Both final germination percentage and germination rate decreased as salinity increased. In higher salinity levels (500 – 700 mM), germination at moderate temperatures was greater than at both lower and higher temperatures. Recovery germination decreased as temperature increased. The lower salinity tolerance during germination in