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Plastic pollution in the soil ecosystem is currently receiving worldwide attention. However, little is known whether the presence of microplastics (MPs) in soil will affect the environmental behavior of pesticide residues in soil. Here, the effect of the addition of new mulch MPs (New-MPs), aged mulch MPs (Aged-MPs) and biodegradable mulch MPs (BioD-MPs) on the adsorption and degradation behaviors of two pesticides (imidacloprid and flumioxazin) in soil was investigated. Three MPs slowed down rapid adsorption stage of pesticides in soil and delayed the time to reach adsorption equilibrium. Adsorption rates: Soil Soil + New-MPs Soil + Aged-MPs Soil + BioD-MPs. Three MPs enhanced the adsorption strength of the soil system for the two pesticides, and the aging treatment of the MPs enhanced this effect. Three MPs affected the degradation process of the two pesticides. New-MPs promoted the degradation of two pesticides imidacloprid and flumioxazin, and the degradation half-lives were shortened to 0.93 and 0.85 times, respectively; while Aged-Mps and BioD-MPs delayed the degradation process of two pesticides, and the degradation half-lives were extended to 1.64 times and 1.21 times, respectively. The effect was more significant with the increase of MPs and pesticides concentration. Pesticide polarity, surface structure and functional groups of MPs are potentially important reasons for the differences in adsorption and degradation of MPs-soil systems. Our findings provide a deep insight into understanding the mechanism of interaction between MPs and pesticide residues in soil environment.

Various 1,3,4-oxadiazole thioether derivatives containing 2-chloro-5-methylene pyridine, 2-chloro-5-methylene thiazole, 3,4-dimethoxy-2-methylene pyridine, and N,N-dimethyl-2-ethylamino moieties were designed, synthesized, and assessed for their antibacterial activities against Xanthomonas oryzae pv. oryzae (Xoo) via the turbidimeter test in vitro. Preliminary bioassay results confirmed good antibacterial activities for most of these compounds. Among these substances, compound 6r showed the best inhibitory effect against Xoo, and its half-maximal effective concentration (EC50) value is 4.78μg/mL, which is superior to that of commercial agent bismerthiazol (87.55μg/mL). We then performed a label-free quantitative proteomic analysis of the response of Xoo to 6r. A total of 1363 proteins were identified in the control and treatment groups. Upon treatment with the minimum inhibitory concentration, 349 proteins were found to be differentially expressed (fold changes>1.5, p

To understand the antibacterial mechanism of the new bactericide 2-(methylsulfonyl)-5- (4-fluorobenzyl)-1, 3, 4-oxadiazole (Generic name: Fubianezuofeng), we performed label-free quantitative proteomics analysis of the response of Xanthomonas axonopodis pv. citri (Xac) strain 29-1 to Fubianezuofeng. A total of 1133 proteins were identified in the treatment and control groups. Upon treatment with the 1/2 minimum inhibitory concentration (MIC), 339 proteins were found to be differentially expressed (fold changes>1.5, p