Effects of temperature and salinity on the seeds germination of Retama raetam (FORSSK.) Webb. scarified with sulfuric acid

Abstract

The present study consists of the elimination of tegumentary inhibition affecting seeds of Retama raetam by the chemical scarification. This pretreatment was carried out using pure sulfuric acid (98 %) and the seeds' germinative behavior was studied in the laboratory under controlled  conditions  of  temperature  and  salinity.  The  results  reveal that  the  chemical scarification by the sulfuric acid during six hours, had favored the germination of seeds which were incapable of germinating. The thermal optimum of germination expreessed by the highest germination capacities and speeds as well as the shortest average times of germination and latency times corresponded to 20 °C and 25 °C. At low temperatures (0 °C and 5 °C) and high temperatures (35 °C and 40 °C), the germination was not possible. The seeds of R. raetam are sensitive to salinity, when the NaCl concentration increases the rate of germination decreases. The  threshold  of  tolerance inhibited. was  recorded  at  272  mM, from  which  the  germination  was inhibited.

Keywords: Retama raetam; chemical scarification; germination; temperature; salinity