Background/Objectives: Petroleum contamination in soil exerts toxic effects on earthworms (Eisenia fetida) through non-polar narcotic mechanisms. However, the specific toxicities of individual petroleum components remain insufficiently understood. Methods: This study investigates the effects of four petroleum components—saturated hydrocarbons, aromatic hydrocarbons, resins, and asphaltenes—on earthworms in artificially contaminated soil, utilizing a combination of biochemical biomarker analysis and metabolomics to uncover the underlying molecular mechanisms. Results: The results revealed that aromatic hydrocarbons are the most toxic fraction, with EC50 concentrations significantly lower than those of other petroleum fractions. All tested fractions triggered notable metabolic disturbances and immune responses in earthworms after 7 days of exposure, as evidenced by significant changes in metabolite abundance within critical pathways such as arginine synthesis, a-linolenic acid metabolism, and the pentose phosphate pathway. According to the KEGG pathway analysis, saturated hydrocarbon fractions induced marked changes in glycerophospholipid metabolism, and arginine and proline metabolism pathways, contributing to the stabilization of the protein structure and membrane integrity. Aromatic hydrocarbon fractions disrupted the arachidonic acid metabolic pathway, leading to increased myotube production and enhanced immune defense mechanisms. The TCA cycle and riboflavin metabolic pathway were significantly altered during exposure to the colloidal fraction, affecting energy production and cellular respiration. The asphaltene fraction significantly impacted glycolysis, accelerating energy cycling to meet stress-induced increases in energy demands. Conclusions: Aromatic hydrocarbons accounted for the highest level of toxicity among the four components in petroleum-contaminated soils. However, the contributions of other fractions to overall toxicity should not be ignored, as each fraction uniquely affects key metabolic pathways and biological functions. These findings emphasize the importance of monitoring metabolic perturbations caused by petroleum components in non-target organisms such as earthworms. They also reveal the specificity of the toxic metabolic effects of different petroleum components on earthworms.

Straw return has potential benefits for soil fertility, environmental sustainability, and yield. However, its effects on pathogen carryover and disease in subsequent crop cycles remain unclear. Wheat is a crucial food source. This study examined the effects of straw return methods—deep plowing (DP), rotary tillage (RT), and deep loosening (DL)—on wheat crown rot. Trials were conducted in fields with maize straw return, and the wheat crown rot incidence and severity were compared after maize straw return. The wheat root microbial communities were assessed using absolute and relative quantification sequencing techniques (AS and RS), and the relationship between changes in the bacterial community and the abundance of crown rot pathogen Fusarium pseudograminearum was explored. DP reduced the crown rot incidence (22.0) and severity (6.8) in subsequent wheat crops, showing values significantly lower than those under RT (64.0 incidence, 24.0 severity) and DL (49.0 incidence, 18.8 severity). Variations in wheat root fungal diversity and composition were observed among methods and soil depths within the DP regime. The abundance of F. pseudograminearum was significantly lower under DP than under RT and DL (RS: less than 0.1% in DP and more than 0.5% in RT and DL; AS: fewer than 10,000 reads in DP and more than 50,000 in RT and DL). The reduced pathogen abundance may be associated with shifts in bacterial genera due to straw return practices. This study shows the importance of selecting appropriate straw return methods to manage wheat crown rot.

A significant number of microorganisms inhabit the intestinal tract or the body surface of insects. While the majority of research on insect microbiome interaction has mainly focused on bacteria, of late multiple studies have been acknowledging the importance of fungi and have started reporting the fungal communities as well. In this study, high-throughput sequencing was used to compare the diversity of intestinal fungi in Delia antiqua (Diptera: Anthomyiidae) at different growth stages, and effect of differential fungi between adjacent life stages on the growth and development of D. antiqua was investigated. The results showed that there were significant differences in the α and β diversity of gut fungal communities between two adjacent growth stages. Among the dominant fungi, genera Penicillium and Meyerozyma and family Cordycipitaceae had higher abundances. Cordycipitaceae was mainly enriched in the pupal and adult (male and female) stages, Penicillium was mainly enriched in the pupal, 2nd instar and 3rd instar larval stages, and Meyerozyma was enriched in the pupal stage. Only three fungal species were found to differ between two adjacent growth stages. These three fungal species including Fusarium oxysporum, Meyerozyma guilliermondii and Penicillium roqueforti generally inhibited the growth and development of D. antiqua, with only P. roqueforti promoting the growth and development of female insects. This study will provide theoretical support for the search for new pathogenic microorganisms for other fly pests control and the development of new biological control strategies for fly pests. Graphical Abstract Three fungal species were found to differ between two adjacent growth stages. These three fungal species including Fusarium oxysporum, Meyerozyma guilliermondii and Penicillium roqueforti generally inhibited the growth and development of D. antiqua, with only P. roqueforti promoting the growth and development of female insects.

Background/Objectives: Many fungi related to Talaromyces verruculosus can degrade a wide range of pollutants and are widely distributed globally. T. verruculosus SJ9 was enriched from fresh strawberry inter-root soil to yield fungi capable of degrading tetracycline, enrofloxacin, and tylosin. Methods: T. verruculosus SJ9 genome was sequenced, assembled, and annotated in this study utilizing bioinformatics software, PacBio, and the Illumina NovaSeq PE150 technology. Results: The genome size is 40.6 Mb, the N50 scaffold size is 4,534,389 bp, and the predicted number of coding genes is 8171. The T. verruculosus TS63-9 genome has the highest resemblance to the T. verruculosus SJ9 genome, according to a comparative genomic analysis of seven species. In addition, we annotated many genes encoding antibiotic-degrading enzymes in T. verruculosus SJ9 through genomic databases, which also provided strong evidence for its ability to degrade antibiotics. Conclusions: Through the correlation analysis of the whole-genome data of T. verruculosus SJ9, we identified a number of genes capable of encoding antibiotic-degrading enzymes in its gene function annotation database. These antibiotic-related enzymes provide some evidence that T. verruculosus SJ9 can degrade fluoroquinolone antibiotics, tetracycline antibiotics, and macrolide antibiotics. In summary, the complete genome sequence of T. verruculosus SJ9 has now been published, and this resource constitutes a significant dataset that will inform forthcoming transcriptomic, proteomic, and metabolic investigations of this fungal species. In addition, genomic studies of other filamentous fungi can utilize it as a reference. Thanks to the discoveries made in this study, the future application of this fungus in industrial production will be more rapid.

In insect–microbe symbiosis, understanding the diversity of associated bacteria is crucial. DNA-dependent sequence methods are widely used to assess microbial diversity in insects, but they cannot distinguish between live and dead microbes. In contrast, RNA-dependent sequencing can identify alive bacterial communities, making them more suitable for evaluating alive microbiota diversity. However, its practical reliability in insect–microbe symbiosis remains poorly validated. This study investigated larval gut bacteria diversity of Delia antiqua, a major pest of Liliaceae crops, by employing both DNA- and RNA-dependent 16S rRNA amplicon sequencing. The reliability of both sequencing methods was evaluated by comparing the effects of synthetic communities (SynComs, constructed according to DNA- or RNA-dependent sequencing) and bacterial communities from wild larvae on axenic larvae. Results revealed significant differences in bacterial community between DNA- and RNA-dependent sequence samples. Compared to bacterial communities from wild larvae, the SynCom constructed based on RNA-dependent sequencing exhibited inhibition effects on D. antiqua larvae survival and body weight, while DNA-dependent SynCom did not, suggesting that DNA-dependent methods were superior for assessing symbiotic microbiota in D. antiqua. This work will provide insights into microbial diversity detection in D. antiqua and offer a framework for other insect–microbe studies.