Effects of fertilizer and waterlogging on the diversity and functioning of the microbial community in greenhouse cultivation soil

Background: Greenhouse cultivation is mainly a monoculture system, which leads to severe soil degradation, with significant changes to the structure of the soil microbial community. The present study aimed to determine the effects of fertilizer and waterlogging (WL) on the microbial community of soil that was continuously monocropped with cucumber in a greenhouse for 3 years (2016-2019). Biolog EcoPlates (TM) and high-throughput sequencing were used to investigate the abundance, structure, and diversity of the soil microbial community. Results: Compared with the initial total soluble salt content (8.65 g/kg), total soluble salt content after WL significantly decreased to 0.597 g/kg. Compared to control (CK) soil, the abundance of fungal species in the chemical fertilizer plus waterlogging (CFWL)-treated soil increased by 40.5%, while bacterial species abundance in the organic fertilizer plus waterlogging (OFWL)-treated soil increased by 10.7%. Furthermore, the relative abundance of Arthrobacter, Geobacter, and Bacillus was higher in OFWL-treated soil than CFWL-treated soil (p<0.01). Conclusions: The application of CFWL to greenhouse soil under continuous monoculture produces fungal-dominated soil, whereas OFWL application alone produces bacterial-dominated soil.