| The current study was conducted to determine whether different agricultural organic waste, namely, chicken manure, vermicompost, mushroom residue, and peat, could be used as carrier for microbial fertilizer by inoculating plant growth-promoting rhizobacteria（PGPR）. PGPR are the rhizosphere bacteria that can enhance plant growth through a wide variety of mechanisms. The potential of PGPR in agriculture is gradually increasing because it offers an attractive way to replace chemical fertilizer use. Therefore, a bacterial strain with known positive effects on plant growth, named Pseudomonas YT3, was selected in the present investigation. Considering the resource utilization of agricultural organic wastes, the physico-chemical properties, bacterial strain release rate, effective live bacteria, and germination index in the 40th day were investigated. The result showed that the water absorption rate of chicken manure was the lowest, whereas the Pseudomonas YT3 release rate, measured at 93.08%, was the highest among all the four organic wastes. In addition, the water absorption rate of mushroom residue was highest, whereas the bacterial strain release rate was the lowest. The phytotoxicity of different organic wastes was measured with the germination index of alfalfa seeds cultured in the microbial fertilizer solution. The results indicated that, all of the germination indices, except for the mushroom residue, were above 80%, and the solution can be beneficial to plant seed development, but with no phytotoxicity. The numbers of these strains on chicken manure, vermicompost, and peat had a significantly increased. On the 30th day after inoculating Pseudomonas YT3, the numbers of the strain were highest at 8.9×108 CFU·g-1, 7.5×108 CFU·g-1, and 5.9×108 CFU·g-1, which were increased by 560%, 326%, and 187% from their initial amounts, respectively. On the 180th day after inoculating the strain, the numbers of Pseudomonas YT3 were lower than their initial amounts. Although mushroom residue had higher initial inoculation amount, the numbers of Pseudomonas YT3 continually decreased with increasing inoculation time. Therefore, chicken manure and vermicompost, especially chicken manure, was better as a carrier for Pseudomonas YT3 than peat. |
