ABSTRACT

Previously, studies of microbial fertilizer were mainly focused on isolation of the functional strains; the comparison among carriers of the fertilizer was seldom studied. In the current paper, we aimed to evaluate the effect of three carriers of microbial fertilizer in saline-alkaline soil. Two Bacillus strains and three carriers, namely activated carbon, spent mushroom substrate and peat, were used to produce microbial fertilizer. Water infiltration and evaporation, microbial community and alfalfa growth were determined. The results showed that the carrier activated carbon accelerated the water infiltration. The microbial communities of the activated carbon and peat carrier treatments were similar. Conversely, the spent mushroom substrate carrier treatment contained a relatively higher abundance of Bacillus and Ilumatobacter and a relatively lower abundance of Arthrobacter, JG30-KF-CM45 and Actinomycetales when compared to the other two treatments. Furthermore, pot experiments demonstrated that the microbial fertilizer with the activated carbon carrier promoted alfalfa growth better than the other two treatments. Overall, the microbial community analysis indicated that the more abundant Bacillus did not promote plant growth in the saline-alkaline soil; instead, the role of activated carbon in saline-alkaline soil remediation was highlighted. This study provides a methodology for microbial fertilizer application in saline-alkaline soil.

摘要

以前，微生物肥料的研究主要集中在功能菌株的分离上；很少研究肥料载体之间的比较。在本文中，我们旨在评估三种微生物肥料载体在盐碱土壤中的作用。两种芽孢杆菌菌株和三种载体，即活性炭、废蘑菇基质和泥炭，用于生产微生物肥料。确定了水的渗透和蒸发、微生物群落和苜蓿生长。结果表明载体活性炭加速了水的渗透。活性炭和泥炭载体处理的微生物群落相似。相反，用过的蘑菇基质载体处理含有相对较高丰度的芽孢杆菌和Ilumatobacter和相对丰度较低的节，JG30-KF-CM45和放线菌目时相比于其他两种治疗方法。此外，盆栽试验表明，含活性炭载体的微生物肥料比其他两种处理更好地促进了苜蓿的生长。总体而言，微生物群落分析表明，更丰富的芽孢杆菌对盐碱土壤中的植物生长没有促进作用；相反，活性炭在盐碱土壤修复中的作用得到了强调。本研究为盐碱地微生物施肥提供了一种方法。