Mitigating Effect of Fulvic Acid Potassium on the Growth of Sabina chinensis under Different Chlorine Salt Stress

【Objective】 In this paper, we studied the growth and physiological characteristics of Sabina chinensis vulgaris container seedlings under high concentration salt stress, and the mitigation effect and difference of fulvic acid potassium on high concentration NaCl and CaCl2 stress. It provides technical support for the management and maintenance of median strip of northern expressway in winter. 【Method】 We used 2-year-old Sabina chinensis container seedlings as study materials during pot experiment, and normal growth as control. The effects of potassium fulvic acid (FA-K) at 0, 0.05%, 0.10%, 0.30% and 0.50% on alleviating high salt stress of 0.7% NaCl and CaCl2 were investigated. The growth indexes of Sabina chinensis seedlings (seedling height growth, ground diameter growth, biomass, root-shoot ratio), photosynthetic pigment content (chlorophyll a, chlorophyll b, total chlorophyll, carotenoid), relative conductivity, MDA content, osmotic adjustment substance content (proline, soluble sugar), superoxide dismutase (SOD) and peroxidase (POD) were measured under various treatments. 【Result】 1) The inhibition effect of 0.7% CaCl2 stress on the growth of Sabina chinensis seedlings was greater than that of 0.7% NaCl stress. Under 0.7% CaCl2 stress, other physiological indexes (chlorophyll a, chlorophyll b, total chlorophyll, MDA, proline content, relative conductivity, POD, SOD activity) were higher than those under NaCl stress except that the content of soluble sugar and carotenoid was lower than that under NaCl stress. 2) Under two kinds of salt stress, fulvic acid potassium increased height growth, ground diameter growth and biomass, increased chlorophyll a, chlorophyll b, total chlorophyll and carotenoid content, decreased relative electrical conductivity and MDA content, and showed a low-high-low trend in SOD and POD activity, prominence acid and soluble sugar content. Under 0.50% FA-K, the seedling growth under the two salt stresses was close to the control. 3) Compared with 0.7% NaCl stress, fulvic acid potassium showed better mitigation effect on 0.7% CaCl2 stress. 【Conclusion】 The result indicated that high salt significantly inhibited the growth and survival of Sabina chinensis, and the inhibition effect of 0.7% CaCl2 was stronger than that of 0.7% NaCl. The stress of NaCl and CaCl2 could be effectively mitigated by fulvic acid potassium, and 0.50% of fulvic acid potassium was most effective. © 2024 Chinese Society of Forestry. All rights reserved.