Germination of Caryopses of the Halophyte: Aeluropus massauensis from Saudi Arabia PDF

Keywords

grass, Saudi Arabia, germination

Abstract

Aeluropus massauensis is a perennial grass. The species dominates one of the communities of the littoral salt marsh vegetation of the Red Sea coast, e.g., at Rabigh. Freshly collected caryopses of A. massauensis were germinated over a range of fluctuating temperature regimes and also in varying salinity levels at two fluctuating temperature regimes. The responses of the caryopses to these environmental variables were compared with those obtained previously by the author and co-workers for Halopeplis perfoliara and Limonium axillare, which inhabit Rabigh salt marsh. The caryopses of A. massauensis germinated rapidly to high percentages over the whole temperature range. The salt tolerance of the species was considerably lower than the salt content in the soil samples (0-5 cm depth) within its habitats. The inhibition of the germination of the caryopses of A. massauensis by excessive salinities (80 and 100 per cent seawater) is due 10 high osmotic potential of the medium. The ecological significance of the responses of the caryopses of A. massauensis to these various environmental variables is discussed.