Development of solid agents of the diphenyl ether herbicide degrading bacterium Bacillus sp. Za based on a mixed organic fertilizer carrier

Abstract

The long-term and widespread use of diphenyl ether herbicides has caused serious soil residue problems and threatens the agricultural ecological environment. The development of biodegrading agents using high-efficiency degrading strains as pesticide residue remediation materials has been widely recognized. In this study, the strain Bacillus sp. Za was used to prepare solid agents for the remediation of diphenyl ether herbicides-contaminated soil. The ratio of organic fertilizer was 1:3 (pig manure: cow dung), the inoculum amount of Za was 10%, the application amount of solid agents was 7%, and the application mode was mixed application, all of which were the most suitable conditions for solid agents. After the solid agents were stored for 120 days, the amount of Za remained above 108 CFU/g. The degradation rates of the solid agents for lactofen, bifenox, fluoroglycofen, and fomesafen in soil reached 87.40, 82.40, 78.20, and 65.20%, respectively, on the 7th day. The application of solid agents alleviated the toxic effect of lactofen residues on maize seedlings. A confocal laser scanning microscope (CLSM) was used to observe the colonization of Za-gfp on the surface of maize roots treated in the solid agents, and Za-gfp mainly colonized the elongation zone and the mature area of maize root tips, and the colonization time exceeded 21 days. High-throughput sequencing analysis of soil community structural changes in CK, J (solid agents), Y (lactofen), and JY (solid agents + lactofen) groups showed that the addition of solid agents could restore the bacterial community structure in the rhizosphere soil of maize seedlings. The development of solid agents can facilitate the remediation of soil contaminated with diphenyl ether herbicide residues and improve the technical level of the microbial degradation of pesticide residues.

Biochar-based Bacillus subtilis inoculant for enhancing plants disease prevention: microbiota response and root exudates regulation

“…The bacterial survival rate of BC@SL was 51.07%, whereas that of SL-44 was only 9.35%. These findings demonstrate that BC@SL was more stable than the liquid microbial inoculant SL-44, and such stability could be conducive to the preservation and transport of inoculants (Zhao et al 2022).…”

“…2d, Additional file 1: Figure S4e, and S4f ). These results demonstrate that BC could provide shelter for SL-44 to better cope with external environmental stresses (Zhao et al 2022), with a more stable population of antipathogenetic bacteria than SL-44 applied alone. In addition, BC@SL promoted plant roots to secrete more antioxidant enzymes in response to Rs stress.…”

“…A significant ) and BPDA (b2, PDA contained 1%BC); c SEM image of BC@SL; d EDS and corresponding elemental mapping of BC@SL; e FTIR spectra of BC and BC@SL; f XPS spectrum of C1s for BC@SL; g XPS spectrum of O1s for BC@ SL; h Zeta potential of SL, BC and BC@SL; i The count and survival rate of bacteria inoculants SL-44 and BC@SL increase was observed in the number of viable bacteria in SL and BC@SL on the fifth weekend, which may be because (1) fungal mycelium secretes rich enzymes, metabolites, antibiotics, etc. to form a microenvironment for microbial growth around fungal mycelium, which is called mycelium, providing nutrients for bacterial growth (Zhang et al 2022) and (2) BC could provide shelter to SL-44 and increase its number (Zhao et al 2022) on the fifth weekend compared with the initial value. Figure 2a and Additional file 1: Figure S3d show that the number of Rs decreased in all treatments and conformed to the following order: RsT < BCRs < SLRs < BC@SLRs, which is relevant to the count of SL-44 in soil as it could inhibit the growth of Rs.…”

Nitroreductase DnrA, Utilizing Strategies Secreted in Bacillus sp. Za and SCK6, Enhances the Detoxification of Acifluorfen

“…Root length, plant height, and fresh weight were assessed as indicators under a photoperiod of 16 h of light (25 °C) and 8 h of darkness (22 °C). 12,28 2.9. Data Processing and Analysis.…”

Molecular genetics of electricity production in bacteria: A review

“…was added to their growing cultures. Most of these mediators are toxic, thus could not be used in open environments which increased the limitations of this process [13,14,15]. However, subsequent studies isolated a strain of Geobacter sulfurreducens that had a high ability to completely metabolize acetate as an electron donor and transfer the electrons obtained directly to the cathode as an electron acceptor without the need of mediators [14].…”