Study Of The Physiological Effect Of CaCl₂and SA On Cold-tolerance Of3Broad-Leaved Evergreen Seedings In Lauraceae

This experiment uses Phoebe bournei (Hemsl.) Yang, Lindera megaphylla Hemsl, Phoebe zhennan, a total of three Broad-Leaved Evergreens in Lauraceae seedlings as experimental materials, calcium chloride (CaCl2) and salicylic acid (SA) as experimental reagents, using a combination of laboratory and field methods, measuring physiological indicators of Phoebe bournei (Hemsl.) under artificial chilling stress and relative conductivity, MDA content, soluble sugar content, soluble protein content, peroxidase activity, chlorophyll content of three plants under natural low temperature stress, designing to reveal the mechanism of its cold hardiness, mainly to study the effects of CaCl2and SA on cold-tolerance of Phoebe bournei (Hemsl.) Yang, Lindera megaphylla Hemsl, Phoebe zhennan seedlings. The experiments explore the applicable concentrations of two reagents to improve the cold-tolerance of three types of seedlings.1. Cacl2and SA effectively elevate POD activity, reduce relative electricity conductivity and MDA conten of Phoebe bournei (Hemsl.) Yang seedlings in the artificial chilling stress (5℃,0℃,-5℃). The experiment showed that the suitable concentration of CaC12and SA can effectively enhance the cold-tolerance of Phoebe bournei (Hemsl.) Yang seedlings between-5℃～5℃. Under different temperature conditions, the effect of different concentrations of reagentswith different concentrations of the same result is not the same, indicating that the physiological status of plants by external environmental factors and factors of the plant’s own, changing very complex2. CaCl2and SA reduce the conductivity value, MDA content, and elevate POD activity, soluble sugar, soluble protein and chlorophyll content of Phoebe bournei (Hemsl.) Yang, Lindera megaphylla Hemsl and Phoebe zhennan seedlings. The experiment showed that CaCl2and SA increased cold resistance of three species of plants. Considering, Improve cold-resistance of Lindera megaphylla Hemsl seedlings when CaCl2concentrations for25mmol/l affecting most pronounced. Improve cold-resistance of Phoebe zhennan seedlings when CaCl2concentrations for5mmol/l affecting most pronounced. Improve cold-resistance of Phoebe bournei (Hemsl.)Yang seedlings when CaCl2concentrations for25mmol/l affecting most pronounced. Improve cold-resistance of Lindera megaphylla Hemsl seedlings when SA concentrations for10mmol/l affecting most pronounced. Improve cold-resistance of Phoebe zhennan seedlings when SA concentrations for10mmol/l affecting most pronounced. Improve cold-resistance of Phoebe bournei(Hemsl.)Yang seedlings when SA concentrations for lmmol/l affecting most pronounced. This shows that deal with different concentrations of reagents on Phoebe bournei (Hemsl.) Yang, Lindera megaphylla Hemsl and Phoebe zhennan seedlings has a cold resistance of interspecific differences.3. The relative conductivity value of Lindera megaphylla Hemsl is lower. The contents of chlorophyll and soluble sugar content of it is higher than Phoebe bournei(Hemsl.)Yang and Phoebe zhennan. POD activity is significantly higher than them. To the extent, Lindera megaphylla Hemsl is more suitable as introduction of garden greening plants.