Abstract:

The changes in growth，physiological and biochemical indexes of 1-year-old Sambucus coreana and Acer ginnala seedlings under different NaHCO₃ stress intensities (CK，1.0，2.0，4.0 g NaHCO₃·kg^-1 media) were tested. The two species able to adapt to the stress of low concentrations of NaHCO₃，while the growth was dramatically inhibited under moderate and high concentrations of NaHCO₃. The livability of Sambucus coreana were 100%，90% and 65% respectively，in the low moderate and high treatments, and that of Acer ginnala was 100%，75% and 55% respectively. There were remarkable intense and duration effects of the salt stress on physiogical indexes of the two species. By the increasing of stress concentration and duration of the stress time，the content of MDA and the relative osmosis of cell membrane significantly increased，and the contents of ASA and GSH also increased，and proline and soluble sugar contents were massively accumulated. Compared to the control，the content of GSH in Sambucus coreana under mild，moderate and severe stresses increased by 68.5%，54.5% and 90.4% at middle stress stage，while that of Acer ginnala increased by 87.9%，124.9% and 96.9% at long-time stress stage，respectively. Compared to the control，the contents of soluble sugar of Sambucus coreana and Acer ginnala at later stress stage increased by 46.7%，38.3%，51.9% and 15.6%，31.8%，22.7%，respectively, under mild, moderate and severe stress. The results suggested that Sambucus coreana and Acer ginnala had tolerance to lower salt stress and could bear the soil environment with 1 g·kg^-1 NaHCO₃. Sambucus coreana had stronger tolerance against carbonate stress than Acer ginnala.

Key words: Sambucus coreana, Acer ginnala, NaHCO₃ stress, salt tolerance