The control of agricultural pests is key to maintain economically viable crops. Increasing environmental awareness, however, is leading to more restrictive European policies regulating the use of certain pesticides due to their impact on human health and the soil system. Given this context, we evaluated the efficacy of three alternatives to the soil fumigant 1,3-dichloropropene (1,3-D), which is currently banned in Europe: two non-fumigant nematicides [oxamyl (OX) and fenamiphos (FEN)] and the soil fumigant dimethyl disulfide (DMDS). We analysed the efficiency of these pesticides against root-knot nematodes and soil fungal pathogens (determined by qPCR) as well as the soil biological quality after treatments application (estimated by enzyme activities). Among treatments, 1,3-D and DMDS significantly reduced nematode populations. FEN was more effective in sandy soil, while OX had no effect in any soil. OX and FEN had no effect on fungal pathogens, whereas DMDS reduced the abundance of Rhizoctonia solani and Fusarium solani at the root level in clay-loam soil. Soil quality decreased after treatment application but then recovered throughout the experiment, indicating the possible dissipation of the pesticides. Our findings support DMDS as a potential sustainable alternative for controlling root-knot nematodes and fungal pathogens due to its effectiveness in both studied soils, although its negative impact on soil biological quality in sandier soils must be taken into account.Main finding of the work. DMDS is a reliable alternative to 1,3-D for controlling agricultural pest but its inhibitory effect on soil enzyme activities varied according to the soil characteristics.

World soils are subjected to a number of anthropogenic global change factors. Although many previous studies contributed to understand how single global change factors affect soil properties, there have been few studies aimed at understanding how two naturally co-occurring global change drivers, nitrogen (N) deposition and increased precipitation, affect critical soil properties. In addition, most atmospheric N deposition and precipitation increase studies have been simulated by directly adding N solution or water to the forest floor, and thus largely neglect some key canopy processes in natural conditions. These previous studies, therefore, may not realistically simulate natural atmospheric N deposition and precipitation increase in forest ecosystems. In a field experiment, we used novel canopy applications to investigate the effects of N deposition, increased precipitation, and their combination on soil chemical properties and the microbial community in a temperate deciduous forest. We found that both soil chemistry and microorganisms were sensitive to these global change factors, especially when they were simultaneously applied. These effects were evident within 2 years of treatment initiation. Canopy N deposition immediately accelerated soil acidification, base cation depletion, and toxic metal accumulation. Although increased precipitation only promoted base cation leaching, this exacerbated the effects of N deposition. Increased precipitation decreased soil fungal biomass, possible due to wetting/re-drying stress or to the depletion of Na. When N deposition and increased precipitation occurred together, soil gram-negative bacteria decreased significantly, and the community structure of soil bacteria was altered. The reduction of gram-negative bacterial biomass was closely linked to the accumulation of the toxic metals Al and Fe. These results suggested that short-term responses in soil cations following N deposition and increased precipitation could change microbial biomass and community structure.

Presence of microorganisms in soils strongly affects mobility of metals. This fact is often excluded when mobile metal fraction in soil is studied using extraction procedures. Thus, the first objective of this paper was to evaluate strain Aspergillus niger’s exometabolites contribution on aluminium mobilization. Fungal exudates collected in various time intervals during cultivation were analyzed and used for two-step bio-assisted extraction of alumina and gibbsite. Oxalic, citric and gluconic acids were identified in collected culture media with concentrations up to 68.4, 2.0 and 16.5 mmol L−1, respectively. These exometabolites proved to be the most efficient agents in mobile aluminium fraction extraction with aluminium extraction efficiency reaching almost 2.2%. However, fungal cultivation is time demanding process. Therefore, the second objective was to simplify acquisition of equally efficient extracting agent by chemically mimicking composition of main organic acid components of fungal exudates. This was successfully achieved with organic acids mixture prepared according to medium composition collected on the 12th day of Aspergillus niger cultivation. This mixture extracted similar amounts of aluminium from alumina compared to culture medium. The aluminium extraction efficiency from gibbsite by organic acids mixture was lesser than 0.09% which is most likely because of more rigid mineral structure of gibbsite compared to alumina. The prepared organic acid mixture was then successfully applied for aluminium extraction from soil samples and compared to standard single step extraction techniques. This showed there is at least 2.9 times higher content of mobile aluminium fraction in soils than it was previously considered, if contribution of microbial metabolites is considered in extraction procedures. Thus, our contribution highlights the significance of fungal metabolites in aluminium extraction from environmental samples, but it also simplifies the extraction procedure inspired by bio-assisted extraction of aluminium by common soil fungus A. niger.

Sugarcane cultivars (Saccharum officinarum L.) are widely cultivated for both sugar and renewable energy in China. The response of rhizosphere fungal composition and diversity to different emerging sugarcane cultivars is limited. Therefore, utilizing high-throughput sequencing, we explored fungal communities’ structure in soils adhering to six sugarcane cultivars’ roots (Guitang 08–120, Regan14-62, Guitang 08–1180, Haizhe 22, Liucheng 05–136, Taitang 22) in Guangxi Province, China. Our results suggested that sugarcane varieties significantly altered rhizosphere soil attributes, with Haizhe 22 having substantially lower soil pH, organic matter (OM), available phosphorus (AP), and soil water contents (SWC) than others cultivars. Different sugarcane varieties did not substantially affected the Shannon fungal diversity index, but the apparent effect on fungal richness was significant. Beta diversity analysis revealed that “Haizhe 22” distinguished the fungal community from the other five cultivars. Soil pH, OM, cultivars, and soil moisture were crucial determinants in shaping soil fungal composition. The Haizhe 22 rhizosphere significantly enriched the operational taxonomic units (OTUs) assigned to two fungal genera (Cephalotheca and Sagenomella), while rhizosphere of other verities significantly enriched the OTUs assigned to four fungal genera (Chaetomium, Chaetosphaeria, Mortierella, and Talaromyces), suggesting their essential role in plant development, disease tolerance, and bioremediation. These findings may help in selecting or breeding innovative genotypes capable of supporting abundant rhizosphere fungi beneficial to plants that would likely improve crops’ agronomic potential and maintain soil ecosystem sustainability.

Dust events impose negative socio-economic, health, and environmental impacts on vulnerable areas and reflect their sources’ physiochemical and biological characteristics. This study aimed to assess the impact of two dust sources on the concentration and diversity of airborne fungi in one of the dustiest areas in the world. This study is the first attempt to investigate the relationship between dust sources fungal community and those in airborne dust. Also, the contribution of dust sources to airborne fungi was estimated. Air masses arriving at the study area were assessed using local wind rose and the HYSPLIT model. Sampling was carried out from airborne dust at the Arvand Free Zone as target areas and soil in the dried parts of the Hor al-Azim and Shadegan wetlands as source areas to explore the relationship between fungi in the dust sources and the downwind area. The samples were analyzed in the lab to extract DNA. The internal transcribed spacer (ITS) regions of the rDNA gene were amplified using the primers ITS1F and ITS4, and then PCR products were sent to the lab for sequencing. The raw DNA data were processed using the QIIME virtual box to pick operational taxonomic units and taxonomy assignments. The most common fungi at the genus level were in the order of Penicillium > Aspergillus > Alternaria > Fusarium > Paradendryphiella > Talaromyces. The similarity between air and soil fungal genera was investigated using richness and diversity indices, the phylogenetic tree, and principal component analysis. The results showed that the community structures of ambient fungi in the Hor al-Azim and Shadegan dust sources were more similar to those on dusty days than non-dusty days. The source tracker model was used to quantify the contributions of known dust sources to airborne fungi. The results showed that the main source of airborne fungi was Hor al-Azim on dusty and non-dusty days. This study’s results can help managers identify and prioritize dust sources regarding fungal species.

Pyrene, a toxic four-benzene-ring that persists in the ecosystem, is highly resistant to degradation. The goal of the research is to screen, isolate, and identify pyrene-degrading filamentous fungi via the molecular biological identification method. The capabilities of identified isolates in biodegradation and transformation of pyrene were also evaluated. Based on the morphological characterization and sequence alignments, results of neighbor-joining phylogenetic tree from 18S rRNA of F03 revealed that genetic similarity had achieved 99% of homology percentage and identified as Trichoderma sp. Trichoderma sp. F03 was able to degrade pyrene (78%) when culture conditions were set at 100 mg/L initial pyrene concentration in culture medium with pH 5 at 27 °C, the use of glucose as a carbon source and polyethylene glycol sorbitan monooleate as a biosurfactant without agitation. Finally, three metabolites, benzoic acid, 3-hydroxybenzoic acid, and acetic acid, were detected during the pyrene degradation process by using gas chromatography–mass spectrometry (GCMS).

The quantification of arsenic biovolatilization by microscopic filamentous fungi Aspergillus clavatus, A. niger, Trichoderma viride and Penicillium glabrum under laboratory conditions is discussed in this article. The fungi were cultivated on a liquid medium enriched with inorganic arsenic in pentavalent form (H₃AsO₄). Filamentous fungi volatilized 0.010 mg to 0.067 mg and 0.093 mg to 0.262 mg of arsenic from cultivation systems enriched with 0.25 mg (5 mg.l-¹ of arsenic in culture media) and 1.00 mg of arsenic (20 mg.l-¹ of arsenic in culture media), respectively. These results represent the loss of arsenic after a 30-day cultivation from cultivation systems. The production of volatile arsenic derivatives by the A. niger and A. clavatus strains was also determined by hourly sorption using the sorbent Anasorb (CSC) on the 29th day of cultivation.

Soil fungi have been widely studied, but the effects of heavy metal contamination at various levels as well as the abundance and diversity of heavy metal tolerant fungi in the contaminated paddy soils are still unknown. The purpose of this study is to analyze the adaptability of fungi at different levels of heavy metal contamination to identify species that have strong adaptability to heavy metals. In this research, the technology of high-throughput sequencing was applied to study fungal communities in severe level (SL), moderate level (ML), light level (LL), and clean level (CL) for soil samples polluted by heavy metal, as well as to analyze the relations between environmental variables and fungal communities. The spearman analysis showed that 6 dominant fungal phyla and 18 dominant fungal genera were significantly correlated with these environmental variables. The α-diversity indexes of the soil fungal community from SL, ML, and CL were, mostly, drastically higher than the LL samples (p < 0.05). Meanwhile, Ascomycota, the main fungal phylum, was spotted to yield a strong tolerance towards heavy metals, especially in ML. The most dominant genera of tolerant fungi in this area, which are Aspergillus, Penicillium, and Fusarium, could absorb and transport the heavy metals with the help of nutrients under certain heavy metal contamination levels. Therefore, this study indicated that some fungi, which have strong biodegradability on heavy metals, can reduce toxicity of heavy metals and create a proper soil environment to grow food crops. Graphical abstract

Because of its persistent usage and broad-spread applicability, chlorpyrifos with high potential damage to non-target organism can be found widely in the environment. However, the relevant researches about the effects of chlorpyrifos on soil fungi, an important part of microorganisms in the planting soil, are very limited, especially when chlorpyrifos is applied in actual agricultural practices. In this study, the soils, planted with Brassica juncea (L.) Czerniak (big mustard), treated with chlorpyrifos were analyzed during vegetable growth to be harvested. The effects of chlorpyrifos on fungal abundance and community structure were determined by quantitative polymerase chain reaction (qPCR) and denaturing gradient gel electrophoresis (DGGE). The results revealed that chlorpyrifos was removed only 15.20 % on the 15th day after being sprayed. Chlorpyrifos caused inhibition on soil fungi diversity and fungal abundance significantly decreased from the early days after application. Furthermore, an obvious change in fungal community structure was found in the treatments compared with the controls, especially a significant change of Fusarium sp., which maintained stable abundance in the controls but fell sharply when chlorpyrifos started to be used and then significantly increased in the treatments, even over the controls finally. In contrast to the controls, the effects from chlorpyrifos could change soil fungal structure by affecting soil pH, while the other soil physicochemical properties without significant influence from chlorpyrifos.

Biodegradation of chlorpyrifos was studied in mineral medium and soil with a novel fungal strain JAS1 isolated from a paddy field soil. The molecular characterization based on 18S rRNA sequence homology confirmed its identity as Aspergillus terreus. The 300-mg L⁻¹ chlorpyrifos and its major metabolite 3,5,6-trichloro-2-pyridinol (TCP) were completely degraded within 24 h of incubation in the mineral medium. In soil enriched with chlorpyrifos and nutrients (carbon, nitrogen, and phosphorous), A. terreus JAS1 was able to degrade chlorpyrifos and its metabolite TCP (300 mg kg⁻¹ soil) in 24 and 48 h, respectively. The soil was spiked with chlorpyrifos (300 mg kg⁻¹ soil) devoid of nutrients and the fungal strain was capable of degrading both chlorpyrifos and TCP in 24 and 48 h, respectively. The course of the degradation process was studied using high-performance liquid chromatography and Fourier transform infrared analyses. These results showed that the chlorpyrifos-degrading fungal strain had the potential to degrade the pesticide-contaminated agricultural soils even without addition of nutrients.