| 刊名 | Agricultural Biotechnology |
| 作者 | Na WANG, Hang WANG, Yiran ZHU, Siying ZHU, Xiajuan XIE, Yanliang CHU |
| 作者单位 | College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China |
| DOI | DOI:10.19759/j.cnki.2164-4993.2025.03.018 |
| 年份 | 2025 |
| 刊期 | 3 |
| 页码 | 75-83 |
| 关键词 | Endophytic bacterium; Paemibacillus sp.; Siderophore; Promoting growth |
| 摘要 | [Objectives] This study was conducted to explore the culture conditions for siderophore production and preliminarily investigate the growth-promoting effects of strains. [Methods] Endophytic bacteria secreting siderophores were isolated and screened from the roots of the plant Saposhnikovia divaricata (Trucz.) Schischk. The siderophore-producing capability was confirmed through qualitative detection and gene cluster analysis. [Results] The screened endophytic bacterium PB-2 belonged to the genus Paenibacillus sp. and could produce catechol-type or carboxylate-type siderophores. When cultured in MKB medium with 15 g/L glycerol as the carbon source and 6 g/L glycine as the nitrogen source for 3 d, the strain exhibited efficient siderophore secretion. Appropriate concentrations of Fe³⁺, Co²⁺, Cu²⁺ and Al³⁺ promoted siderophore production, with 15 μmol/L Fe³⁺ being the most effective. Under the combined influences of siderophores, volatile compounds and other factors, strain PB-2 altered the root morphology of mulberry seedlings and increased their biomass. The primary root length decreased by 9.15%, while the number and length of root hairs increased by 37.93% and 16.37%, respectively, and the total biomass increased by 10.26%, all showing significant differences (P < 0.05). Additionally, strain PB-2 enhanced the activity of defense-related enzymes in mulberry seedling leaves. The activities of superoxide dismutase (SOD) and peroxidase (POD) increased significantly (P < 0.05) by 247.27% and 189.47%, respectively, compared with the control group. The activities of phenylalanine ammonialyase (PAL) and polyphenol oxidase (PPO) also showed varying degrees of increase. [Conclusions] This study provides a theoretical basis for rational utilization of endophytic growth-promoting strains secreting siderophores in the sustainable development of agriculture. |
