Abstract:Using annual Astragalus membranaceus var. mongholicus seedlings as materials, we investigated the response of biennial A. membranaceus var. mongholicus to different fertilizers (Water soluble fertilizer of alginic acid, Water soluble fertilizer of humic acid, Organic fertilizer, Biological fertilizer of microorganism inoculant and Compound fertilizer) as well as its physiological photosynthetic mechanism in salinealkali land, which provides reference for the popularization and planting of A. membranaceus var. mongholicus in salinealkali land. The results of the study showed that: in salinealkali land, the application of biological fertilizer of microorganism inoculant had no significant effect on the stress resistance, photosynthesis, growth characteristics, yield and quality of A. membranaceus var. mongholicus; the application of compound fertilizer significantly increased the growth of aboveground part of A. membranaceus var. mongholicus, while had no significant effect on the yield, and significantly reduced its stress resistance, photosynthesis and pharmacodynamic components; the application of water soluble fertilizer of alginic acid, water soluble fertilizer of humic acid and organic fertilizer significantly increased the stress resistance, photosynthesis, underground growth, yield and quality of A. membranaceus var. mongholicus. Among them, the yield of A. membranaceus var. mongholicus applied with organic fertilizer was the highest, reaching 7 046.2 kg·hm-2. The pharmacodynamic components of A. membranaceus var. mongholicus applied with water soluble fertilizer of humic acid and organic fertilizer were the highest, the content of AS was above 0.13%, and the content of C7G was above 0.06%. In summary, Organic fertilizer had the highest yield and ensured high pharmacodynamic components of A. membranaceus var. mongholicus, which can be considered as the best fertilizer.