Abstract:

Dry seeds of Populus ussuriensis collected from Heilongjiang area were carried by the recoverable satellite for mutagenesis. Then the growth traits and antioxidant enzymes activities of seedlings from the spaceflight-treated seeds and controls were analyzed. The results showed that the growth traits of the seedlings after spaceflight varied to some degree, but most of the variation was not remarkable. There were no significant changes in soluble protein content，malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in seedlings with response to spaceflight treatment. However，activities of ascorbate peroxidase (APX) and guaiacol peroxidase (POD) in the poplar seedlings after spaceflight were significantly higher than those from the ground control. It suggested that space condition altered the poplar traits in some degree，and the higher antioxidant enzymes might failitate themselves to avoid some damage from active oxygen.

Key words: Populus ussuriensis, space mutation, growth trait, antioxidant enzyme