College of Resources and Environment, Yangtze University, Wuhan, China.
China University of Geosciences, Wuhan 430074, China.
Ecotoxicol Environ Saf. 2021 Jun 1;215:112162. doi: 10.1016/j.ecoenv.2021.112162. Epub 2021 Mar 20.
Decapitation and root cutting can influence plant physiological features, such as height, dry weight, and transpiration rate, which partly determine the success of phytoremediation. In this study, the effects of three root cutting intensities (10%, 25%, and 33%), decapitation, and their combination on the phytoremediation efficiency of Celosia argentea were evaluated. Decapitation increased the biomass yield of C. argentea roots and leaves and significantly improved the species' Cd decontamination ability. Root cutting, especially 33% cutting treatment, decreased the root dry weight. The 10% and 25% root cutting treatments increased the leaf biomass yield by 58.6% and 41.4%, respectively, compared with the untreated control, even compensating for the loss of roots, but 33% root cutting decreased the leaf dry weight. Low and moderate root cutting intensity (10% and 25%) increased the leaf Cd content by 33.4% and 24.9%, respectively, and was associated with improved transpiration rate. The highest root and leaf dry weights were observed for the combination of decapitation and 10% root cutting, which increased the biomass yield of underground and aerial parts by 109.9% and 286.2%, respectively. In addition, decapitation offset the negative effects of 33% root cutting on plant growth, indicated by the higher dry weight relative to the control. Decapitated C. argentea accumulated 11.0, 7.5, and 0.7 times more Cd with the 10%, 25%, and 33% root cutting treatments, respectively, compared with the control. The combination of root cutting and decapitation was a practicable and economical method of enhancing the Cd decontamination capacity of C. argentea.
斩首和断根会影响植物的生理特征，如株高、干重和蒸腾速率，这些特征在一定程度上决定了植物修复的成败。本研究评估了三种断根强度（10%、25%和 33%）、斩首和两者组合对鸡冠花（Celosia argentea）植物修复效率的影响。斩首增加了鸡冠花根和叶的生物量产量，并显著提高了该物种的镉净化能力。断根，尤其是 33%的断根处理，降低了根的干重。与对照相比，10%和 25%的断根处理分别使叶片生物量增加了 58.6%和 41.4%，甚至弥补了根的损失，但 33%的断根处理降低了叶片干重。低强度和中等强度的断根（10%和 25%）分别使叶片中的镉含量增加了 33.4%和 24.9%，同时伴随着蒸腾速率的提高。在断根和 10%断根的组合处理下，观察到根和叶的干重最高，分别增加了地下和地上部分的生物量产量 109.9%和 286.2%。此外，与对照相比，斩首抵消了 33%断根对植物生长的负面影响，表现为干重更高。与对照相比，断根的鸡冠花在 10%、25%和 33%断根处理下分别积累了 11.0、7.5 和 0.7 倍的镉。断根和斩首的组合是提高鸡冠花镉净化能力的一种可行且经济的方法。
