Community Structure and Function of Epiphytic Bacteria Associated With Myriophyllum spicatum in Baiyangdian Lake, China

Abstract

Epiphytic bacteria on the surfaces of submerged macrophytes play important roles in the growth of the host plant, nutrient cycling, and the conversion of pollutants in aquatic systems. A knowledge of the epiphytic bacterial community structure could help us to understand these roles. In this study, the abundance, diversity, and functions of the epiphytic bacterial community of Myriophyllum spicatum collected from Baiyangdian Lake in June, August, and October 2019 were studied using quantitative PCR (qPCR), high-throughput sequencing, and the prediction of functions. An analysis using qPCR showed that the epiphytic bacteria were the most abundant in October and the least abundant in August. High-throughput sequencing revealed that Proteobacteria, Gammaproteobacteria, and Aeromonas were the dominant phylum, class, and genus in all the samples. The common analyses of operational taxonomic units (OTUs), NMDS, and LDA showed that the epiphytic bacterial communities were clustered together based on the seasons. The results of a canonical correlation analysis (CCA) showed that the key water quality index that affected the changes of epiphytic bacterial community of M. spicatum was the total phosphorus (TP). The changes in abundance of Gammaproteobacteria negatively correlated with the TP. Predictive results from FAPROTAX showed that the predominant biogeochemical cycle functions of the epiphytic bacterial community were chemoheterotrophy, nitrate reduction, and fermentation. These results suggest that the epiphytic bacterial community of M. spicatum from Baiyangdian Lake varies substantially with the seasons and environmental conditions.

The Relationship between Brachionus calyciflorus-Associated Bacterial and Bacterioplankton Communities in a Subtropical Freshwater Lake

“…The functions of microbial communities, predicted through software such as FAPROTAX, are widely used in microbial ecology [ 71 ]. The most important biogeochemical cycle functions of AB and NB communities include plastic degradation, phototrophic, photosynthetic autotrophic, and oxygen-producing photoautotrophic functions, while the most prominent biogeochemical cycle functions of B. calyciflorus -associated bacterial community were plastic degradation, chemoheterotrophy, and aerobic chemoheterotrophy.…”

“…Therefore, it is speculated that although the impact of microplastics on B. calyciflorus may be deepened due to bioaccumulation [ 78 ], the associated bacterial community has improved the tolerance of B. calyciflorus to plastic pollution through a specific composition. Chemoheterotrophy and aerobic chemoheterotrophy can use organic matter to meet all or major carbon requirements under different oxygen conditions [ 79 ], which are the most dominant putative functions predicted by various biologically associated bacterial communities [ 71 , 80 , 81 ]. Nitrogen is the other most important element in a lake ecosystem.…”

Analysis of diversity and function of epiphytic bacterial communities associated with macrophytes using a metagenomic approach

“…Differences in phenolic content among plant species may be a major factor contributing to the differences in epiphytic bacterial communities [ 3 ]. In contrast, epiphytic bacterial communities of M. spicatum from different locations exhibited similar core bacterial species [ 18 ], suggesting that conspecifics maintain similar core epiphytic bacterial communities despite environmental variations. However, our knowledge on this topic remains limited.…”

Prediction of Total Phosphorus Concentration in Macrophytic Lakes Using Chlorophyll-Sensitive Bands: A Case Study of Lake Baiyangdian

“…Lake Baiyangdian is the largest freshwater wetland in the North China Plain, and the largest lake in Hebei Province [32][33][34]. It is a typical plant-dominated shallow freshwater lake; also a significant freshwater breeding base in northern China, with an extremely high ecological and economic status [35][36][37][38][39]. Lake Baiyangdian is also instrumental in maintaining the wetland ecosystem's balance, regulating the climate, improving the temperature and humidity, replenishing the groundwater, and protecting biodiversity and rare species [40].…”