The phosphate group functionalized metal-organic frameworks (MOFs) as the adsorbent for removal of U(VI) from aqueous solution still suffer from low adsorption efficiency, due to the low grafting rate of groups into the skeleton structure. Herein, a novel phosphate group functionalized metal–organic framework nanoparticles (denoted as Fe3O4@SiO2@UiO-66-TPP NPs) designed and prepared by the chelation between Zr and phytic acid, showing fast adsorption rate and outstanding selectivity in aqueous media including 10 coexisting ions. The Fe3O4@SiO2@UiO-66-TPP was properly characterized by TEM, FT-IR, BET, VSM and Zeta potential measurement. The removal performance of Fe3O4@SiO2@UiO-66-TPP for U(VI) was investigated systematically using batch experiments under different conditions, including solution pH, incubation time, temperature and initial U(VI) concentration. The adsorption kinetics, isotherm, selectivity studies revealed that Fe3O4@SiO2@UiO-66-TPP NPs possess fast adsorption rates (approximately 15 min to reach equilibrium), high adsorption capacities (307.8 mg/g) and outstanding selectivity (Su = 94.4%) towards U(VI), which in terms of performance are much better than most of the other magnetic adsorbents. Furthermore, the adsorbent could be reused for U(VI) removal without obvious loss of adsorption capacity after five consecutive cycles. The research work provides a novel strategy to assemble phosphate group-functionalized MOFs.

Verticillium dahliae is a soil-borne hemi-biotrophic fungal pathogen and inflicts major losses in agricultural production worldwide. Although the pathogenicity of the fungus and plant immunity have been extensively studied, how cotton leaf necrosis is induced by defoliating strains of V. dahliae is poorly understood. In this study, reference-grade genomes were determined for two representative V. dahliae isolates: V991, which is defoliating and aggressive, and 1cd3-2, which is non-defoliating and has weak pathogenicity. Transcriptome analysis showed that cotton resistance to V. dahliae mainly depends on cell wall structure or physical barrier generation in the early stage of infection (3-9 days post inoculation, dpi). However, a large number of pathogenic factors could be detected from 12 dpi and accumulated quickly in cotton stems, accompanied by the burst of reactive oxygen species (ROS), leaf necrosis and defoliation. A V991 specific virulence gene SP3 was identified through comparative genome analysis and found to be highly expressed after colonization. Knock-out of SP3 clearly attenuated pathogenicity, with less ROS produced. These results indicate that disease symptoms in cotton may be due to abnormal immune activation and excessive ROS induced by the pathogen. To further investigate this, Polyethyleneimine coated MXene quantum dots (PEI-MQDs), a type of nano material that possesses the ability to remove ROS in vitro, were used. Cotton seedlings maintain ROS homeostasis with enhanced peroxidase (POD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities after exogenous treatment with PEI-MQDs and show significant tolerance to V. dahliae isolate V991. Our results suggest that excessive ROS and constitutive immune activation in cotton induced by the defoliating strain of V. dahliae is responsible for disease symptoms such as leaf necrosis, and PEI-MQDs application improve cotton tolerance to V. dahliae by maintaining ROS homeostasis.

Pearl oil apricot is rich in nutrition, but easily gets quality deterioration in short term after harvest which significantly reduces its commercial value. Studies were conducted to determine the effects of polyethylene (PE), PE/1-mmethylcyclopropene (1-MCP), and PE/ethylene absorbent treatment on the respiration rate, ethylene production, fruit firmness, soluble solids content, and color variation of apricot during storage period varied at 21.5, 0, and 1.5 8C. The respiration rate of apricot was inhibited and respiration intensity peak was delayed 7 days in PE/1-MCP treated group. The ethylene peak was also delayed effectively, and ethylene production significantly decreased after 1-MCP and ethylene absorbent treatment. The decrease of apricot fruit firmness was suppressed in PE/1-MCP and PE/ethylene absorbent treatment at 21.5 8C. The lustrousness and color of apricot were maintained very well after PE/1-MCP treatment at 21.5 8C. In conclusion, the best way for the storage of pearl oil apricot was PE/1-MCP treatment and 21.5 8C preservation. Practical applicationsThe optimal treatment efficiently inhibited respiration intensity and ethylene release of pearl oil apricot fruit, suppressed firmness decreasing and quality deterioration, increased consumers' acceptability. This treatment is safe, economic, and applicable, which can be used to maintain the quality of pearl oil apricot theoretically and technically.

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