Cucumber Fusarium wilt caused by Fusarium oxysporum f. sp. cucumerium (FOC), is a prevalent soil-borne disease. In this study, Bacillus subtilis JNF2, isolated from the high incidence area of cucumber Fusarium wilt in Luoyang, demonstrated significant inhibitory effects on FOC and promoted cucumber seedling growth. The biocontrol mechanism of strain JNF2 were elucidated through morphological observation, physiological and biochemical experiments, and whole genome sequence analysis. Pot experiments revealed an 81.33 ± 0.21% control efficacy against Fusarium wilt, surpassing the 64.10 ± 0.06% efficacy of hymexazol. Seedlings inoculated with JNF2 exhibited enhanced stem thickness and leaf area compared to control and hymexazol-treated plants. Physiological tests confirmed JNF2’s production of indole-3-acetic acid (IAA), siderophores, and hydrolytic enzymes, such as β-1,3-glucanase, amylase, and protease, which inhibited FOC growth and promoted plant development. Genome analysis identified genes encoding antimicrobial peptides and hydrolases, as well as a novel glycocin synthetic gene cluster. These findings underscore B. subtilis JNF2’s potential as a biocontrol agent for sustainable cucumber cultivation.

Oil Spillage is considered one of the environmental disasters due to the release of hydrocarbons into the aquatic environment, causing destructive effects. Usually, it occurs accidentally or intentionally, mostly resulting from human activities. Effective degradation of these spills is vital to preserving the aquatic ecosystem. Recently, combining state-of-the-art nanotechnology with degrading bacteria is an area of great interest and opens new paths for addressing oil/water pollution issues. In this context, the current study assesses the synergetic effect of a hybrid of green-synthesized magnetite nanoparticles and oil-degrading bacteria on oil spill removal in vitro conditions. Bacterial isolates were isolated from water samples collected from Sharkia, Qalyubia, and Minufiya Governorates in Egypt. Effective oil-degrading strains were identified by 16S rRNA gene sequencing. Magnetite nanoparticles (AL-MNPs) were synthesized from Artemisia leaf extract through green synthesis and characterized using UV-Vis spectroscopy, TEM, EDX, and FTIR. Bacterial growth was compared with the effect of AL-MNPs at various concentrations and exposure durations. Results indicated that the interaction between AL-MNPs and bacteria greatly enhanced oil degradation. With optimal conditions (35°C, pH 7, 300 mg/l oil, and 0.04 g AL-MNPs), almost 90% of oil was degraded after 3 days. AL-MNPs alone degraded about 59%, and bacteria alone degraded 72–80% in the same period. GC-MS analysis verified that the system degraded almost 50% lower-chain alkanes (C9–C22) and 30% higher-chain alkanes (C23–C26). Furthermore, the recyclability of the AL-MNPs was also explored, with slight loss of removal efficiency upon repeated usage, but with superior performance. This demonstrates the long-term capability of the AL-MNPs-bacteria system. Correspondingly, the eco-friendly synthesis of AL-MNPs using plant extracts reinforces their role as a sustainable and cost-effective alternative to oil spill degradation techniques. The most astounding result, the synergizing effect between oil-degrading bacteria, environmentally isolated, and AL-MNPs. This not only enhances the degradation process but also contributes to a greener, more integrated remediation strategy that aligns with circular economy and environmental protection goals.

Rhizosphere microorganisms play an important role in the health and development of root systems. Investigating the microbial composition of the rhizosphere is central to understanding the inter-root microbial function of Arundo donax under various cultivation conditions. To complement the metagenomic study of the Arundo donax rhizosphere, here, an amplicon-based metagenomic survey of bacteria and fungi was selected as a practical approach to analyzing the abundance, diversity index, and community structure of rhizosphere bacteria and fungi, as well as to study the effects of different cultivation methods on rhizosphere microbial diversity. Next-generation sequencing and QIIME2 analysis were used. The results indicated that microbial community richness, diversity, and evenness of the hydroponic samples were lower than those of soil samples when examining the α diversity indices of bacteria and fungi using Chao1, ACE, and Shannon metrics. In particular, the relative abundances of Proteobacteria, Rhizobiales, and Incertae sedis in hydroponic materials were higher, while Basidiomycota, Ascomycota, and Actinobacteriota dominated the flora in soil materials when comparing the numbers of OTUs and the ACE community richness estimator. Furthermore, the rhizosphere of hydroponic A. donax contained a higher abundance of nitrogen-fixing bacteria and photosynthetic bacteria, which contribute to root formation. Additionally, there was a significant presence of Basidiomycota, Ascomycota, and Actinobacteriota in soil A. donax, which can form hyphae. This reveals that the microbial community composition of the A. donax rhizosphere is significantly different under various cultivation conditions, suggesting that employing two distinct culturing techniques for Arundo donax may alter the microbiome. Furthermore, it provides technical support for the synergistic interaction between Arundo donax and rhizosphere microorganisms so as to better use the relationship between Arundo donax and basic microorganisms to solve the problems of Arundo donax growth and ecological restoration.