The Physiological Effects Of High Temperature Stress On The Ornamental Grass - Fine Stems Of Stipa And Induced Heat Resistance

Stip tenuissima native to Chile, Argentina, New Mexico and Texas, is a densely tufted perennial russock ornamental grass that leaves thin soft, long duration of flower, strong stress resistance, extensive management and was used widely in landscape, slope protection, indoor garden an so on. In recent years, greenhouse effect is growing that endanger plants, so heat tolerance of ornamental grass has become one of the new topics on the present.Using "Pony Tails" as test materials, study effect that high temperature stress on membranes permeability, MDA content, Free proline content, soluble protein content,chlorophyll content and antioxidant enzymes. In the meantime, did thermo-tolerance induction by salicylic acid and heat acclimation treatment, and analyzed the effect of different treat methods on biochemical and biochemical. And draw some opinions which some coincided with former viewpoints while other different opinions were put forward. Results were as follows:1. Proved that relative electric conductivity, proline content and MDA content of leaves were increased while chlorophyll content declined, but salicylic acid and heat acclimation could weaken them, relax the injured of "Pony Tails" under the heat stress.2. Considering the salicylic acid induction,0.5mmol/L SA can effectively improve the heat resistance of "Pony Tails".3. The activities of POD of "Pony Tails" seeding positively related to the temperature, salicylic acid and heat acclimation induction have no effects on POD activity, "Pony Tails" seeding which induced by salicylic acid or heat acclimation can keep a higher activity.4. In contrast with former viewpoint, it was concluded from the test that CAT activity can not be an index of evaluating "Pony Tails" heat resistance.5. The result showed that there are not correlation between the content of soluble protein and time of high temperature.