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Arabidopsis thaliana was selected as model organisms to investigate the toxic effect and mechanism of four kinds of imidazolium and pyridinium ionic liquids (ILs) on plant seedling taproots. After exposure to ILs, the growth of seedling taproots was significantly inhibited in a dose-dependent manner. The toxicity of ILs on seedling taproots was [Bmim][BF4] > [Bmpy][BF4] > [Bmim][Br] > [Bmpy][Br]. The reduction of seedling root cell vitality, aggravation of seedling root cell death, and repression of gravitropic growth responses were observed. The amounts of H2O2 and ROS in seedlings were enhanced with increasing concentrations of ILs. Moreover, the expression levels of cdc2a and pcna1 genes were decreased after exposure to ILs. Our results suggest that ILs can induce the overproduction of ROS in A. thaliana seedling taproots and thus cause oxidative damage to seedling taproots. Meanwhile, ILs alter the expression patterns of two cell cycle-related genes and hence cause the seedling taproot growth inhibition. This work provides an integrated understanding of the toxic effect and mechanism of ILs on A. thaliana seedlings at the molecular and physiological level and also provides theoretical basis and reference for the environmental safety evaluation of ILs, prior to their widespread use and release.
相似文献The immobilization agent was the key factor that determined the success of remediation of heavy metal polluted soil. In this study, mercapto-grafted palygorskite (MP) as a novel and efficient immobilization agent was utilized for the remediation of Cd-polluted paddy soil in pot trials, and the remediation mechanisms were investigated in the aspect of soil chemistry and plant physiology with different rice cultivars as model plants. Mercapto-grafted palygorskite at applied doses of 0.1–0.3% could reduce Cd contents of brown rice and straws of different cultivars significantly. Both reduced DTPA-extractable Cd contents in rhizosphere and non-rhizosphere soil and decreasing Cd contents in iron plaques on rice root surfaces confirmed that MP was an efficient immobilization agent for Cd pollutant in paddy soil. In the aspect of soil chemistry, the pH values of rhizosphere and non-rhizosphere soils had no statistical changes in the MP treatment groups, but their zeta potentials decreased obviously, indicating that MP could enhance the fixation or sorption of Cd on soil compositions. In the aspect of antioxidant system, MP could increase POD activity of rice roots significantly to alleviate the stress of Cd to roots, and resulted in the decrease of T-AOC, SOD, and CAT activities of rice roots of the selected cultivars. MP had no inhabitation or enhancement effects on TSH of rice roots but enhance the contents of MTs and NPT to binding Cd to complete detoxification process. MP as a novel and efficient immobilization agent could complete the remediation effects through soil chemistry and plant physiological mechanisms.
相似文献Implications: The performances of biofilters with three different media depths (0.17, 0.33, and 0.50 m) and three different media moisture contents (45%, 55%, and 67% [wet basis]) were compared to remove gases from a swine barn. Using wood chips and compost mixture as the biofilters media, the combination of 0.33 m media depth and 55% media moisture content is recommended to obtain good reduction of NH3 and H2S, and to simultaneously prevent elevated emission of N2O and large pressure drop across the media. 相似文献