Glutathione-dependent redox homeostasis is critical for chlorothalonil detoxification in tomato leaves.

Glutathione plays a critical role in plant growth, development and response to stress. It is a major cellular antioxidant and is involved in the detoxification of xenobiotics in many organisms, including plants. However, the role of glutathione-dependent redox homeostasis and associated molecular mechanisms regulating the antioxidant system and pesticide metabolism remains unclear. In this study, endogenous glutathione levels were manipulated by pharmacological treatments with glutathione synthesis inhibitors and oxidized glutathione. The application of oxidized glutathione enriched the cellular oxidation state, reduced the activity and transcript levels of antioxidant enzymes, upregulated the expression level of nitric oxide and Ca2+ related genes and the content, and increased the residue of chlorothalonil in tomato leaves. Further experiments confirmed that glutathione-induced redox homeostasis is critical for the reduction of pesticide residues. RNA sequencing analysis revealed that miRNA156 and miRNA169 that target transcription factor SQUAMOSA-Promoter Binding Proteins (SBP) and NUCLEAR FACTOR Y (NFY) potentially participate in glutathione-mediated pesticide degradation in tomato plants. Our study provides important clues for further dissection of pesticide degradation mechanisms via miRNAs in plants.

[Effects of urban wetlands with different shapes on the temperature and humidity of ambient environment.] / 不同形状城市湿地对周边环境温湿度的影响.

To quantify the effects of urban wetlands on temperature and humidity of ambient environment, five urban wetlands with different shapes and surroundings were selected in Daqing City, and the air temperature and relative humidity were investigated in spring, summer and autumn using small-scale quantitative measurement method. The results indicated that the urban wetlands with different shapes all could decrease the temperature and increase the humidity, with the effect being strongest in summer, followed by in spring, and the smallest effect in autumn. The shape of the urban wetland had significant effect on temperature and humidity, which decreased in the order of irregular-shaped wetland > regular-shaped wetland (subcircular-shaped wetland, subcuboid-shaped wetland) > long-shaped wetland. The diurnal variation of temperature and humidity was influenced by the ambient temperature, namely the effect of wetlands was weak in morning and evening, but strong at noon. The maximum effect occurred at12:00-14:00 in spring and autumn, and at 14:00-16:00 in summer.