Soil bacterial communities of three types of plants from ecological restoration areas and plant-growth promotional benefits of Microbacterium invictum (strain X-18)

Abstract

Microbial-assisted phytoremediation promotes the ecological restoration of high and steep rocky slopes. To determine the structure and function of microbial communities in the soil in response to changes in soil nutrient content, the bacterial communities of rhizospheric soil from three types of plants, i.e., Robinia pseudoacacia, Pinus massoniana, and Cynodon dactylon, were analyzed using Illumina sequencing technology. High-quality sequences were clustered at the 97% similarity level. The dominant genera were found to be RB41, Gemmatimonas, Sphingomonas, Bradyrhizobium, and Ellin6067. The Tukey HSD (honestly significant difference) test results showed that the abundance of RB41 and Gemmatimonas were significantly different among three types of plants (p < 0.01). The relative abundances of RB41 (13.32%) and Gemmatimonas (3.36%) in rhizospheric soil samples from R. pseudoacacia were significantly higher than that from P. massoniana (0.16 and 0.35%) and C. dactylon (0.40 and 0.82%), respectively. The soil chemical properties analyses suggested that significant differences in rhizospheric soil nutrient content among the three plant types. Especially the available phosphorus, the content of it in the rhizospheric soil of R. pseudoacacia was about 280% (P. massoniana) and 58% (C. dactylon) higher than that of the other two plants, respectively. The soil bacterial communities were further studied using the correlation analysis and the Tax4Fun analysis. A significant and positive correlation was observed between Gemmatimonas and soil nutrient components. Except total nitrogen, the positive correlation between Gemmatimonas and other soil nutrient components was above 0.9. The outcomes of these analyses suggested that Gemmatimonas could be the indicator genus in response to changes in the soil nutrient content. Besides, the genes involved in metabolism were the major contributor to soil nutrients. This study showed that soil nutrients affect the soil bacterial community structure and function. In addition, pot experiments showed that Microbacterium invictum X-18 isolated from the rhizospheric soil of R. pseudoacacia significantly improved soil nutrient content and increased R. pseudoacacia growth. A significant increase in the numbers of nodules of R. pseudoacacia and an increase of 28% in plant height, accompanied by an increase of 94% in available phosphorus was measured in the M. invictum X-18 treatment than the control treatment.

Changes in grassland soil types lead to different characteristics of bacterial and fungal communities in Northwest Liaoning, China

“…In this study, the relative abundance of Subgroup 6 of temperate steppe-sandy soil was significantly lower than that of other grassland soil types, while the soil organic carbon content was similarly significantly lower than that of other grassland soil types ( Table 2 ). The relative abundance of RB41 is somewhat representative of inter-root soil nutrient changes, and there is a significant positive correlation between them ( Liu et al, 2022 ). The soil nutrient content of temperature step sandy-soil in this study is the lowest ( Table 2 ), which explains why its relative abundance of RB41 is significantly lower than that of other grassland soil types.…”

Trichoderma spp. promotes ginseng biomass by influencing the soil microbial community

“…There was a significant and positive correlation between Gemmatimonas and soil nutrient components, and thus Gemmatimonas might be an indicator genus in response to changes in soil nutrient contents. Besides, Gemmatimonas can solubilize insoluble elements, such as phosphorus, and induce plant stress resistance or produce antifungal antibiotics, which have been proven to promote plant growth and enhance nutrient uptake ( Shang and Liu, 2020 ; Liu C. et al, 2022 ). Recent studies have detailed the role of Sphingomonas species in plant growth promotion via the production of phytohormones and increased stress tolerance ( Matsumoto et al, 2021 ; Jin et al, 2022b ; Lombardino et al, 2022 ).…”

Actinobacteria diversity associated with marine sediments and a wetland system, Agulhas-South Africa

“…Members of this genus have also been isolated from diverse environments, including marine sediments, estuaries, forest and agricultural soils, volcanic ash, marble, a hot spring, and marine sponges, and it is therefore not surprising that this genus was detected in both the SF and ANP sites (Wang et al 2023). Members of the genus Microbacterium play an important role in the health of soil (e.g., the release of essential nutrients, plant growth promotion, and removal of toxic metals) (Gómez-Ramírez et al 2015;Liu et al 2022). They are also highly adaptive and have been found in diverse environments, including the high-altitude Atacama Desert (Mandakovic et al 2020) and various marine environments (Kageyama et al 2007;Williams et al 2007).…”