Abstract: In order to study plant growth-promoting activities of endophytic nitrogen-fixing bacteria in faba bean tissues, the related bacteria were isolated from leaves and roots of faba beans’ seedling and analyzed the relationship between the ability of dissolving phosphate and potassium and the ability of nitrogen fixation, cellulase production and pectinase production of these bacteria to identify potential strain that promote plant growth through.  8 strains were isolated from the seedling, in which 7 strains could dissolve inorganic phosphorus, 2 strains could dissolve potassium, 4 strains could product cellulose and 2 strains could product pectase. Sl24-3 from leaves had the highest activity of nitrogenase, and the secretory ability of cellulase and pectinase; SR23-1 had the ability of dissolving inorganic phosphorus and potassium. These results showed that nitrogen fixing bacteria in Vicia faba seedlings obviously promoted the growth, among which SL24-3 and SR23-1 were potential dominant growth promoting bacteria. This study  excavated the potential excellent growth promoting bacteria, which provided the theoretical basis for the in-depth study of endophyte promoting plant growth, and had practical value and significance.

Key words: faba bean (Vicia faba L.), endophyte, nitrogen-fixing bacteria, growth-promoting activities

摘要： 为研究蚕豆内生固氮菌的促生长特性，对蚕豆幼苗叶和根中的内生固氮菌进行分离纯化，并测定这些菌的溶磷溶钾能力与产固氮酶、纤维素酶和果胶酶等酶的能力，确定潜在的促植物生长菌株。从蚕豆幼苗的叶和根中分离得到了8株内生固氮菌，其中7株有溶无机磷能力，2株有溶钾能力，4株有产纤维素酶能力，2株有产果胶酶能力；叶中SL24-3菌株的固氮酶活最高，还有纤维素酶和果胶酶的分泌能力，根中SR23-1固氮菌有溶解无机磷和溶解钾的能力。这些结果表明，蚕豆幼苗内生固氮菌的促生长特性明显，其中SL24-3和SR23-1固氮菌是潜在的优势促生长菌。挖掘了潜在的优良促生菌，为内生菌促进植物生长的深入研究提供理论依据，具有实际价值和意义。

关键词: 蚕豆, 内生菌, 固氮菌, 促生长特性