Effects of PEG priming on germination and seedlings growth of accelerated ageing oat seeds

In order to determine the effects of polyethylene glycol (PEG) priming on the germination and seedlings growth of ultradried oat seeds, the present study measured the indices including germination percentage, lengths of roots and shoots, weights of roots and shoots of ultradried (4% moisture content) oat (Avena sativa) seeds which were accelerated ageing for 48 d at 45 ℃ and primed with different concentrations of polyethylene glycol (PEG) solutions (0, -0.3, -0.6, -0.9 and -1.2 MPa) for 0, 3, 6 and 12 h. The results showed that the germination percentage of aged oat seeds significantly decreased (P0.05) after priming at high osmotic potential of PEG (0 and -0.3 MPa) whereas significantly increased (P0.05) after priming at low osmotic potential (-0.9 and -1.2 MPa). The length of roots increased significantly (P0.05) but the length of shoots, and the fresh weights of roots and shoots significantly decreased (P0.05) after PEG priming. These results indicated that the effects of PEG priming on the germination and seedlings growth of ultradried oat seeds were closely related with its osmotic potential, priming time and their interactions which suggests the further research about how to prime ultradried oat seeds after ageing with PEG in agricultural production need to be conducted.