Abstract:We took the adzuki bean cultivar ‘Jin adzuki bean 5’ and growth promoting bacteria Bacillus ZJMP5 as materials, set different nitrogen dosage and concentration of bacteria treatments, and determined agronomic characters, physiological characteristics and nitrogen content under different treatments by pot experiments at seedling stage. The effect of different Bacillus ZJMP5 and nitrogen treatments on growth and development of adzuki bean seedlings was analyzed, and the optimum growth promoting bacteria concentration level was screened. The aim is to improve the seedling quality and nutrient absorption and utilization efficiency of adzuki bean, and provide a theoretical basis for high yield and high quality cultivation. The results showed that: (1) under the same concentration of bacteria fluid, plant height, stem diameter, leaf area, shoot dry weight, root dry weight, root area, root volume and average root diameter initially increased and then decreased with increasing nitrogen application rate; However the max root length showed a decline; Furthermore, the contents of soluble sugar and MDA in the roots decreased firstly and then increased with the increase of nitrogen application rate, while the activities of SOD, POD in root and root activities initially increased and then decreased with increasing nitrogen rate; the soluble protein content in the root, NR activity and nitrogen uptake of plant rose with increasing nitrogen rate. (2) Under the equal amount of nitrogen fertilizer, in addition to soluble sugar and MDA contents in roots with the increase of bacteria concentration firstly decreased and then increased. The other indexes showed a trend of increasing firstly and then decreasing; All the indexes in addition to the low nitrogen level (50 mg·kg-1), the concentration of 108 cfu·mL-1 bacteria solution reached the maximum value, and the other nitrogen levels reached the highest value at the concentration of 107 cfu·mL-1 bacteria solution. The study found that reasonable combined application of Bacillus ZJMP5 and nitrogen was beneficial to the nitrogen absorption and growth of adzuki bean, 100 mg·kg-1 was the best nitrogen (pure nitrogen) level, and 107 cfu·mL-1 was the best concentration of bacteria, and the agronomic characters, root activity and protective enzyme activities and nitrogen content of the seedlings treated with the combination of the two reached a higher level; Excessive application of nitrogen, bacteria, or the unreasonable proportion of bacteria and nitrogen will lead to dry matter accumulation and nitrogen limitation of seedlings, and then inhibit the normal growth of plants.