【Objective】We aimed to explore the mechanism by which Burkholderia pyrrocinia JK-SH007, a gram-negative bacterium, promotes plant growth; we explored the effects of siderophores on pathogenic fungal activity and plant growth. 【Method】 A sample of JK-SH007-siderophores was isolated and purified using column chromatography, and the siderophore structure was identified using high-performance liquid chromatography and liquid chromatography-mass spectrometry. We cultivated three pathogens that cause poplar canker (Cytospora chrysosperma, Phomopsis macrospora and Fusicoccum aesculi) with siderophore samples to measure pathogen inhibition, and recorded the dry weight of mycelium at the end of the cultivation period. We compared the effects of a JK-SH007-siderophore solution, a JK-SH007 bacterial re-suspension, and a standard siderophore, Deferroamine B solution (DFOB) on plant growth (seed germination, cucumber seedling growth and tomato fruiting).【Result】Compared to DFOB, the JK-SH007-siderophore sample was more effective at inhibiting fungal growth. The pathogenic fungi were inhibited by (89±0.9)%, (76±0.6)% and (90±0.7)%, forC. chrysosperma, P. macrospora and F. aesculin, respectively. Compared to the JK-SH007 re-suspension, the JK-SH007-siderophore solution resulted in better seed germination and higher seedling vigor; however, there were no significant differences for cucumber seedling growth or tomato fruiting. 【Conclusion】We applied a pure siderophore sample, extracted and purified using chromatography, to plants, and compared this with a bacterial re-suspension sample and a standard commercial product. The pure siderophore sample strongly promoted plant growth and the application of a pure siderophore solution can achieve better anti-fungal effects than DFOB, a result which should inform future commercial development of JK-SH007 as a bio-fertilizer.