• Energy Research
• 2021-2025close

Plant–microbial relations have not yet been fully disclosed in natural or seminatural ecosystems, nor in novel ecosystems developing spontaneously on post-coal mine heaps. The aim of this study was to determine which factor, biotic (plant taxonomic diversity vs. plant functional diversity) or abiotic (physicochemical substrate parameters), affects the biomass of soil microbial communities the most, as well as soil in situ respiration in novel ecosystems. The study was carried out on unreclaimed plots selected according to four different combinations of taxonomic and functional plant diversity. Additionally, plots on a reclaimed heap served as a comparison between the two management types. The biomass of several soil microbial groups was analysed using phospholipid fatty acids profiles. We detected that soil microbial biomass was more impacted by abiotic parameters (explaining 23% of variance) than plant diversity (explaining 12% of variance). Particularly, we observed that substrate pH was the most important factor shaping microbial community biomass, as shown in the RDA analysis. The highest microbial biomass was found in plots with low taxonomic and functional diversity. This finding can be explained by the fact that these plots represented a more advanced phase of vegetation development in the early stages of plant succession.

Crop infections by fungi lead to severe losses in food production and pose risks for human health. The increasing resistance of pathogens to fungicides has led to the higher usage of these chemicals, which burdens the environment and highlights the need to find novel natural biocontrol agents. Members of the genus Streptomyces are known to produce a plethora of bioactive compounds. Recently, researchers have turned to extreme and previously unexplored niches in the search for new strains with antimicrobial activities. One such niche are underground coal mine environments. We isolated the new Streptomyces sp. MW-W600-10 strain from coal mine water samples collected at 665 m below ground level. We examined the antifungal activity of the strain against plant pathogens Fusarium culmorum DSM62188 and Nigrospora oryzae roseF7. Furthermore, we analyzed the strain’s biosynthetic potential with the antiSMASH tool. The strain showed inhibitory activity against both fungi strains. Genome mining revealed that it has 39 BGCs, among which 13 did not show similarity to those in databases. Additionally, we examined the activity of the Streptomyces sp. S-2 strain isolated from black soot against F. culmorum DSM62188. These results show that coal-related strains could be a source of novel bioactive compounds. Future studies will elucidate their full biotechnological potential.