Hu Yanmei, Zhang Peng, Zhang Xing, Liu Yuqing, Feng Shanshan, Guo Dawei, Nadezhda Tcyganova, Song Zijie, Dang Xiuli
College of Land and Environment, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Northeast Key Laboratory of Conservation and Improvement of Cultivated Land, Ministry of Agriculture and Rural Affairs, Shenyang Agricultural University, Shenyang 110866, P. R. China.
School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, B15 2TT Birmingham, United Kingdom.
J Agric Food Chem. 2021 May 5;69(17):4981-4991. doi: 10.1021/acs.jafc.1c00733. Epub 2021 Apr 26.
Previous studies have suggested that multiwalled carbon nanotubes (MWCNTs) promote plant growth; however, the mechanism is yet to be fully understood. In this study, the effects of MWCNTs (20, 100, and 500 mg/L) on the carbon (C) and nitrogen (N) metabolism in maize were studied to explore the molecular mechanism of the action of MWCNTs on plants. The results showed that 100 mg/L MWCNTs increased the shoot fresh and dry weight, root fresh weight, and seedling length while other doses showed no significant effects. Further studies showed that 100 mg/L MWCNTs increased the chlorophyll content, transpiration rate, stomatal conductance, and intercellular CO concentration, by 50.6%, 60.8%, 47.2%, and 32.1%, respectively. Activities of key enzymes including sucrose synthase (SS), sucrose phosphate synthase (SPS) and phosphoenolpyruvate carboxylase (PEPC) that are involved in the carbon metabolism, and nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthetase (GOGAT) that are involved in N metabolism, were all upregulated by 100 mg/L MWCNTs, which contributed to the increase of the accumulation of carbohydrates (sugar and starch), soluble protein, and N in plants. These findings suggest that MWCNTs can improve plant growth by regulating the key enzymes involved in C and N metabolism thereby enhancing the carbohydrate production and the use of N and improving plant growth. This study provides significant insights into the molecular mechanism of the positive effects of MWCNTs on plants and provide a basis for the agricultural application of MWCNTs.
先前的研究表明，多壁碳纳米管（MWCNTs）可促进植物生长；然而，其作用机制尚未完全明确。本研究通过探究MWCNTs（20、100和500 mg/L）对玉米碳（C）和氮（N）代谢的影响，来探索MWCNTs对植物作用的分子机制。结果显示，100 mg/L的MWCNTs可增加地上部鲜重和干重、根鲜重以及幼苗长度，而其他剂量则无显著影响。进一步研究表明，100 mg/L的MWCNTs可使叶绿素含量、蒸腾速率、气孔导度和细胞间CO浓度分别增加50.6%、60.8%、47.2%和32.1%。参与碳代谢的关键酶，如蔗糖合酶（SS）、蔗糖磷酸合酶（SPS）和磷酸烯醇式丙酮酸羧化酶（PEPC），以及参与氮代谢的硝酸还原酶（NR）、谷氨酰胺合成酶（GS）和谷氨酸合成酶（GOGAT）的活性，均被100 mg/L的MWCNTs上调，这有助于植物中碳水化合物（糖和淀粉）、可溶性蛋白和氮积累量的增加。这些发现表明，MWCNTs可通过调节参与碳和氮代谢的关键酶来改善植物生长，从而提高碳水化合物产量以及氮的利用效率，促进植物生长。本研究为MWCNTs对植物产生积极影响的分子机制提供了重要见解，并为MWCNTs在农业中的应用提供了依据。
