Research on the physiological characteristics of Miscanthus sinensis seedlings under the treatments of complex saline-alkaloid stress

Soil salinization is prevalent in the world. The increasingly salinization seriously threatens the growth and development of plants, which leads to the reduction of plant species. Miscanthus sinensis, which possesses good economic efficiency and ecological benefits, was a sort of emerging energy plant. In this study, M. sinensis introduced from A Jialing of Benxi City in Liaoning Province were used as materials. Through simulating the saline-alkali soil environment of Daqing in northeast of China which include low(4.147 5, 8.295 0 g·L-1), middle(12.442 5 g·L-1) and high concentration(16.590 0, 20.737 5 g·L-1), we studied each physiological index of the seedlings when they were in the complex saline-alkaloid stress treatment. The study found:When M. sinensis seedlings were in complex saline-alkaloid stress treatment, each index of CK group had a little change over time; the chlorophyll content in low concentration treatment showed a trend of rising first then falling; while in middle and high concentration treatment, the chlorophyll content dropped; the relative electrical conductivity and MDA content increasedover time; and the SOD, POD, CAT, APX, GR activity, ASA, GSH content and root activity were increased in low concentration, but in the treatment of high concentration, these indexes showed a trend of rising first then falling. This study basically defined the range of the saline-alkaloid tolerance of M. sinensis which can provide a theoretical basis for the salt-tolerant screening and applications in landscape of energy plants like M. sinensis in the future.