Abstract:
Seed dormancy is a major constraint in seedling establishment in desert habitats, Seeds of C. patelliforme were collected from natural population in desert areas. dried and then stored for 2 and 5-years at room temperature, The experiments of seed viability and germination at different temperatures (15, 20, 25, 30, 25/15, 35/15, 25/5ºC), light (0h, 14h, 24h), moisture (0, 10.6, 16.5, 21.3, 25.5%) and salinity (0, 50, 100, 200, 300 mM) stress was conducted to evaluate the change of seed viability and germination in seed storage. The seed viability remained to be 100%. The optimal temperature for germination was changed from 25/15ºC (28.00±2.31%) to 25/5ºC (82.67±7.05%%) with the storage length increased from 2 to 5-years. and FGP at 5-year storage were higher than those at 2-year storage, but the differences were significant only at 25ºC and 25/5ºC. Difference between light treatments were not significant All the germination values in PEG-6000
and NaCl concentrations at 5-year storage were higher than those at 2-year storage. The maximum of IGP and FGP were obtained at 10.6% PEG-6000 or 50mM NaCl concentrations at 5-year storage, the RGP in seed storage were increased with the increased PEG-6000 and NaCl concentrations. A 5-year storage at room temperature significantly enhanced the germination percentage of selected species by breaking dormancy and improved the germinability in moisture and salinity stress. This is beneficial to understand the formation mechanism of persistent soil seed-bank and establishing the artificial vegetation in desert areas.
