Abstract:fluorescent pseudomonads can promote mycelia growth and development of some mushroom, such as Agaricus bisporus, Pleurotus ostreatus, and Pleurotus eryngii. It remains poorly characterized whether fluorescent pseudomonas has similar effect on other cultivated mushroom and what is the mechanism. A strain of fluorescent pseudomonad was isolated from wheat rhizosphere and named Pseudomonas sp. P2-10. The level of partial 16S rDNA sequence similarity between strain P2-10 and the fluorescent Pseudomonas species from GenBank ranged from 94% to 98%. The highest 16S rDNA sequence similarity (98%) was observed between strain P2-10 and P. putida IAM 1236T, P. Koreensis Ps 9-14T, P. pavonaceae IAM 1155T, P. jessenii CIP 105274T, and P. umsongensis Ps 3-10T. With addition of bacterial culture strain P2-10 and its supernatant to cottonseed hull media, mycelia of P. ostreatus Td 300, P. eryngii X6, and Coprinus comatus R7 grew faster and fruit body yield of P. ostreatus and P. eryngii were significantly higher than that of control. Similarly adding P2-10 culture to axenic casing soil of C. comatus R7 also stimulated basidiome initiation. The substance for those effects was in cultural solution of strain P2-10, and was similar to that of ethylene inhibitor AgNO3 and CoCl2. Strain P2-10 contained the enzyme 1-aminocyclopropane-1-carboxylate (ACC) deaminase and can utilize ACC as a sole source of nitrogen. Results of this research strongly suggest that inoculation of the mycelia with the fluorescent pseudomonas may promote mycelia growth, basidiome initiation, and enhance fruit body yield of P. ostreatus, P. eryngii, and C. comatus. The mechanism may be that ACC deaminase degrades ACC and decreases ethylene synthesis by edible fungi, subsequently relieves the inhibitory action of ethylene to mycelia growth and fruit body development of edible fungi.