To establish a safe, efficient, and simple biocontrol measure for gray mold disease caused by Botrytis cinerea, the basic characteristics and antifungal activity of KRS005 were studied from multiple aspects including morphological observation, multilocus sequence analysis and typing (MLSA–MLST), physical-biochemical assays, broad-spectrum inhibitory activities, control efficiency of gray mold, and determination of plant immunity. The strain KRS005, identified as Bacillus amyloliquefaciens, demonstrated broad-spectrum inhibitory activities against various pathogenic fungi by dual confrontation culture assays, of which the inhibition rate of B. cinerea was up to 90.3%. Notably, through the evaluation of control efficiency, it was found that KRS005 fermentation broth could effectively control the occurrence of tobacco leaves gray mold by determining the lesion diameter and biomass of B. cinerea on tobacco leaves still had a high control effect after dilution of 100 folds. Meanwhile, KRS005 fermentation broth had no impact on the mesophyll tissue of tobacco leaves. Further studies showed that plant defense-related genes involved in reactive oxygen species (ROS), salicylic acid (SA), and jasmonic acid (JA)-related signal pathways were significantly upregulated when tobacco leaves were sprayed with KRS005 cell-free supernatant. In addition, KRS005 could inhibit cell membrane damage and increase the permeability of B. cinerea. Overall, KRS005, as a promising biocontrol agent, would likely serve as an alternative to chemical fungicides to control gray mold.
This study investigated the aerobic biodecolorization of azo dyes by Shewanella oneidensis MR-1. S. oneidensis MR-1 can rapidly degrade azo dyes under aerobic conditions, even at high concentrations of up to 270 mg/L, demonstrating remarkable dye decolorization capabilities. This decolorization efficiency persists even under high concentrations of oxygen. The introduction of different environmental metal ions led to either inhibitory or stimulatory effects on the decolorization of Methyl Orange and Amaranth. Furthermore, the addition of extracellular electron shuttles and electron scavengers confirmed that dyes were being reduced via electron transfer, and the decolorization capability of S. oneidensis MR-1 correlated with electron density. Our study unveils the rapid degradation ability of S. oneidensis MR-1 for dyes under aerobic conditions, which is closely linked to its electron transfer capacity. This research holds significant implications for a deeper understanding of the biodegradation mechanisms of azo dyes under aerobic conditions.
Soybean (Glycine max) is a globally important source of protein and oil, and its capacity for biological nitrogen fixation (BNF) underpins its strategic role in sustainable agriculture. However, BNF efficiency is highly sensitive to abiotic stresses, and conventional agronomic interventions struggle to simultaneously optimize nodulation, nitrogenase activity, and stress resilience. Agricultural nanotechnology offers a unique avenue to address this bottleneck by modulating the tripartite nanomaterial–rhizobium–soybean interaction at multiple scales. This review systematically examines (1) nanomaterial design strategies tailored to the rhizosphere and nodule microenvironments; (2) the ‘Rhizosphere–Nodule–System’ (RNS) cascade model, which integrates rhizosphere interfacial events, nodule metabolic reprogramming, and systemic stress signaling; and (3) field-level efficacy, genotype-dependent responses, and barriers to scalable application. By elucidating the mechanistic logic by which nanotechnology coordinates BNF enhancement with abiotic stress tolerance, this framework provides theoretical support for the targeted deployment of nano-agricultural technologies in soybean production systems.