Department of Civil and Environmental Engineering, Shantou University, No 243 Daxue Road, Shantou, Guangdong Province, 515063, China.
School of Environmental Science and Engineering, Tianjin Polytechnic University, No. 399 Binshui West Road, Xiqing District, Tianjin, 300387, China.
Plant Physiol Biochem. 2020 Sep;154:287-294. doi: 10.1016/j.plaphy.2020.06.021. Epub 2020 Jun 17.
The application of graphene oxide (GO) in the environment can have a positive or negative effect on the toxicity of pollutants, but the effect of GO on cadmium (Cd)-stressed lettuce has not yet been thoroughly studied. Therefore, we assessed the potential effects of foliar GO sprays on photosynthesis and antioxidant systems in Cd-stressed lettuce. We found that the foliar application of 30 mg L of GO could significantly reduce signs of Cd toxicity in lettuce. We observed increased net photosynthetic rates, stomatal conductance, transpiration rates, chlorophyll content, primary maximum photochemical efficiency of photosystem II, actual quantum yield, photosynthetic electron transport rates, ribulose-1,5-bisphosphate carboxylase and oxygenase concentrations, and biomass in Cd-stressed lettuce treated with GO. In addition, the foliar application of 30 mg L of GO reduced the accumulation of the reactive oxygen species O·̄ and HO, malondialdehyde content, and the activity of antioxidant enzymes. The decreased antioxidant enzyme activity could have been due to the decrease in reactive oxygen species. Cd pollution is highly destructive to agricultural products, and the foliar application of GO provides a new potential tactic to improve the tolerance of plants to heavy metals.
氧化石墨烯（GO）在环境中的应用可能对污染物的毒性产生积极或消极的影响，但 GO 对镉胁迫生菜的影响尚未得到彻底研究。因此，我们评估了叶面喷施 GO 对镉胁迫生菜光合作用和抗氧化系统的潜在影响。我们发现，叶面喷施 30mg/L 的 GO 可以显著减轻生菜的镉毒性症状。我们观察到，在 Cd 胁迫的生菜中，GO 处理组的净光合速率、气孔导度、蒸腾速率、叶绿素含量、光系统 II 原初最大光化学效率、实际量子产量、光合电子传递速率、核酮糖-1,5-二磷酸羧化酶和加氧酶浓度以及生物量均有所增加。此外，叶面喷施 30mg/L 的 GO 降低了活性氧物种 O·̄和 HO、丙二醛含量和抗氧化酶的活性。抗氧化酶活性的降低可能是由于活性氧的减少。镉污染对农产品具有高度破坏性，而叶面喷施 GO 为提高植物对重金属的耐受性提供了一种新的潜在策略。
