Soil salinization is considered a major global environmental problem due to its adverse effects on agricultural sustainability and production. Compost is an environmentally friendly and sustainable measure used for reclaiming saline–sodic soil. However, the responses of the physiological characteristics of alfalfa and the structure and function of rhizosphere fungal communities after compost application in saline–sodic soil remain elusive. Here, a pot experiment was conducted to explore the effect of different compost application rates on soil properties, plant physiological traits, and rhizosphere fungal community characteristics. The results showed that compost significantly increased soil nutrients and corresponding soil enzyme activities, enhanced leaf photosynthesis traits, and ion homeostasis compared with the control treatment. We further found that the rhizosphere fungal communities were dominated by Sodiomyces at the genus level, and the relative abundance of pathogenic fungi, such as Botryotrichum, Plectosphaerella, Pseudogymnoascus, and Fusarium, declined after compost application. Moreover, the α-diversity indexes of the fungal community under compost application rates of 15% and 25% significantly decreased in comparison to the control treatment. The soil SOC, pH, TP, and TN were the main environmental factors affecting fungal community composition. The leaf photosynthetic traits and metal ion contents showed significantly positive correlations with Sodiomyces and Aspergillus. The fungal trophic mode was dominated by Pathotroph–Saprotroph–Symbiotroph and Saprotroph. Overall, our findings provide an important basis for the future application of microbial-based strategies to improve plant tolerance to saline-alkali stress.
Larch wood, a prevalent cultivation medium for Ganoderma tsugae, has yet to be scrutinized concerning the differential impacts of sterilized and non-sterilized substrates on the growth and development of this fungus. Our present investigation sought to elucidate these effects in a forest-like environment. After larch wood segments were sun-dried, they were divided into two groups; one group was bagged and autoclaved, while the other group was bagged without any treatment. Subsequently, all segments were inoculated with the G. tsugae strain HLXL1 and ensconced under the canopy of a Pinus koraiensis forest, thereby approximating the conditions of natural growth. Wild G. tsugae was used as the control. Data on agronomic traits, production days, fruiting body yield, and effective constituent content were analyzed. The results indicated no significant differences between sterilized and non-sterilized substrates in terms of agronomic traits. However, the mineral content and bioactive compounds in G. tsugae fruiting bodies significantly differed across various growth stages. The outcomes were optimal for non-sterilized substrates, followed by sterilized substrates, while the wild strains were markedly less effective than the cultivated ones.
Coal plays a vital role in energy production, but its combustion releases SO2, causing serious environmental problems. In this study, indigenous microorganisms with sulfur-metabolism potential were isolated from raw coal and evaluated for coal biodesulfurization. The isolated strain, Arthrobacter sp. DBW, degraded 50% of DBT within 100 h and reduced the total sulfur content of coal by 42%. Since pyrite remained after treatment, the sulfur removal was mainly attributed to organic sulfur removal. Mechanistic analysis indicated that Arthrobacter sp. DBW may remove organic sulfur through enzyme binding to DBT and subsequent C-S bond cleavage via the 4S pathway. In addition, partial kaolinite dissolution occurred during biodesulfurization, reducing the ash content by 1.06%. These results suggest that Arthrobacter sp. DBW has potential for organic sulfur removal from coal and may help reduce SO2 emissions during subsequent combustion.