Influence of temperature, light and salt on the germination of Deverra triradiata seeds

Deverra triradiata is a perennial glycophytic shrub that grows on coastal sandy dunes in the Arabian Gulf region. Understanding the seed germination response to environmental conditions is essential for assessing the potential use of seeds of this species in the rehabilitation of degraded and endangered terrestrial ecosystems. The germinability of D. triradiata seeds under different temperature, light and salinity conditions was evaluated. Our results showed that D. triradiata seeds could germinate equally well under light and complete darkness. However, germination was reduced significantly at 30/20 degrees C compared with 25/15 degrees C, indicating that the lower temperature is more appropriate for obtaining better seed germination. The highest germination was obtained under non-saline conditions (0 mM NaCl) and increasing salinity (above 100 mM NaCl) progressively inhibited seed germination. Only a few seeds were able to recover their germinability when transferred to distilled water, highlighting the seed sensitivity to salt during germination.