Yang Wei, Dai Huiping, Skuza Lidia, Wei Shuhe
Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Shaanxi Province Key Laboratory of Bio-Resources, College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong 723001, China.
Toxics. 2022 May 19;10(5):266. doi: 10.3390/toxics10050266.
It is very important to increase phytoremediation efficiency in practice in suitable climatic conditions for plant growth through multiple harvests. Solanum nigrum L. is a Cd hyperaccumulator. In the present experiment, after applying different types of N fertilizers (NH4HCO3, NH4Cl, (NH4)2SO4, CH4N2O), root and shoot biomasses and Cd phytoextraction efficiency of S. nigrum effectively improved (p < 0.05). Shoot biomasses of S. nigrum harvested at the first florescence stage plus the amounts at the second florescence stage were higher than those harvested at the maturation stage, which indicates that S. nigrum Cd phytoaccumulation efficiency was higher in the former compared to the latter as there was no clear change in Cd concentration (p < 0.05). The pH value and extractable Cd contents showed no changes, regardless of whether N fertilizer was added or not at different growth stages. In addition, after N fertilizer was applied, H2O2 and malondialdehyde (MDA) contents in S. nigrum in vivo were lower compared to those that had not received N addition (CK); similarly, the concentration of proline was decreased as well (p < 0.05). The activity of the antioxidant enzyme catalase (CAT), harvested at different growth periods after four types of N fertilizer applications, obviously decreased in S. nigrum shoots, while peroxidase (POD) and superoxide dismutase) (SOD) activities increased (p < 0.05). Our study demonstrated that (NH4)2SO4 treatment exerted the most positive effect and CH4N2O the second most positive effect on S. nigrum Cd phytoremediation efficiency in double harvests at florescence stages, and the growth conditions were better than others.
在适合植物生长的气候条件下，通过多次收获提高植物修复效率在实际应用中非常重要。龙葵是一种镉超积累植物。在本实验中，施用不同类型的氮肥（碳酸氢铵、氯化铵、硫酸铵、尿素）后，龙葵的根和地上部生物量以及镉植物提取效率得到有效提高（p < 0.05）。在初花期收获的龙葵地上部生物量加上在盛花期收获的量高于在成熟期收获的量，这表明前者的龙葵镉植物积累效率高于后者，因为镉浓度没有明显变化（p < 0.05）。无论在不同生长阶段是否添加氮肥，pH值和可提取镉含量均无变化。此外，施用氮肥后，龙葵体内的过氧化氢和丙二醛（MDA）含量低于未施氮肥的对照；同样，脯氨酸浓度也降低了（p < 0.05）。在施用四种氮肥后的不同生长时期收获的龙葵地上部中，抗氧化酶过氧化氢酶（CAT）的活性明显降低，而过氧化物酶（POD）和超氧化物歧化酶（SOD）的活性增加（p < 0.05）。我们的研究表明，在花期进行两次收获时，硫酸铵处理对龙葵镉植物修复效率的积极影响最大，尿素次之，且生长状况优于其他处理。
