Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing 210037, China.
Int J Environ Res Public Health. 2019 Jul 9;16(13):2442. doi: 10.3390/ijerph16132442.
The inoculation of beneficial microorganisms to improve plant growth and soil properties is a promising strategy in the soil amendment. However, the effects of co-inoculation with phosphate-solubilizing bacteria (PSB) and N-fixing bacteria (NFB) on the soil properties of typical C-deficient soil remain unclear. Based on a controlled experiment and a pot experiment, we examined the effects of PSB (M: and F: ), NFB (C: and B: ), and combined PSB and NFB treatments on C, N, P availability, and enzyme activities in sterilized soil, as well as the growth of seedlings grow in unsterilized soil. During a 60-day culture, prominent increases in soil inorganic N and available P contents were detected after bacteria additions. Three patterns were observed for different additions according to the dynamic bacterial growth. Synergistic effects between NFB and PSB were obvious, co-inoculations with NFB enhanced the accumulation of available P. However, decreases in soil available P and N were observed on the 60th day, which was induced by the decreases in bacterial quantities under C deficiency. Besides, co-inoculations with PSB and NFB resulted in greater performance in plant growth promotion. Aimed at amending soil with a C supply shortage, combined PSB and NFB treatments are more appropriate for practical fertilization at intervals of 30-45 days. The results demonstrate that co-inoculations could have synergistic interactions during culture and application, which may help with understanding the possible mechanism of soil amendment driven by microorganisms under C deficiency, thereby providing an alternative option for amending such soil.
向土壤中接种有益微生物以改善植物生长和土壤特性是一种很有前途的土壤改良策略。然而，在典型的 C 亏缺土壤中，同时接种解磷细菌（PSB）和固氮细菌（NFB）对土壤特性的影响尚不清楚。本研究通过控制实验和盆栽实验，研究了 PSB（M： 和 F： ）、NFB（C： 和 B： ）以及 PSB 和 NFB 联合处理对灭菌土壤中 C、N、P 有效性和酶活性的影响，以及未灭菌土壤中 幼苗的生长情况。在 60 天的培养过程中，细菌添加后土壤无机 N 和有效 P 含量明显增加。根据细菌生长的动态，不同添加物有三种模式。NFB 和 PSB 之间存在协同作用，NFB 共接种可增强有效 P 的积累。然而，在第 60 天，由于 C 亏缺下细菌数量的减少，土壤有效 P 和 N 减少。此外，PSB 和 NFB 的共接种促进了植物生长。针对 C 供应短缺的土壤改良，PSB 和 NFB 的联合处理更适合在 30-45 天的间隔进行实际施肥。结果表明，共接种在培养和应用过程中可能存在协同相互作用，这有助于理解 C 亏缺下微生物驱动土壤改良的可能机制，从而为改良这种土壤提供了一种替代选择。
