title: Amending the seedling bed of eggplant with biochar can further immobilize Cd in contaminated soils.
abstract: Untreated municipal sewage is a potential source of Cd but has been used for irrigating vegetables in many countries in recent years. In growing vegetables and fruits in greenhouses, seedling breeding method is generally used in which the seedlings are transplanted into soils together with their seedling culture. Biochar has been increasingly used to amend soils contaminated by heavy metals, but there are few studies on the effectiveness of different ways of applying the biochar. In this paper, we investigated the efficacy of immobilizing Cd by amending eggplant seedling bed with biochar before transplanting them to biochar-amended soil contaminated by Cd. The results showed that, in comparison with traditional seedling method (without adding biochar), amending the seedling bed by biochar not only had a positive effect on plant growth and production, but further reduced the Cd concentration in the roots, shoots and the fruits by 12.2%, 12.5% and 18.5%, respectively. Furthermore, it increased the pH in rhizosphere to 8.83, reduced the exchangeable Cd concentration in soil by 28.6%, and decreased the Cd bio-accumulation factor from 0.36 to 0.32. Phytochelatin synthesis could be induced when plants are exposed to Cd and it has been used in the literature as a biomarker for evaluating metal toxicity. Our results showed that the seedling culture amended with biochar reduced phytochelatin synthesis in both roots and shoots. It can therefore be concluded that amending the eggplant seedlings bed with biochar can further enhance the effectiveness of remediating Cd contamination in soil after transplanting the plants into soil also amended with biochar.
  We found a new method to further immobilize Cd in contaminated soils by amending the seedling bed with biochar.
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Zhongyang
authors: Z
authors: Li
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China. Electronic address: qxb6301@sina.cn.
authors: Xuebin
authors: X
authors: Qi
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Xiangyang
authors: X
authors: Fan
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Zhenjie
authors: Z
authors: Du
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Chao
authors: C
authors: Hu
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Zhijuan
authors: Z
authors: Zhao
authors: School of Environmental and Rural Science, University of New England, New South Wales 2351, Australia.
authors: Yunusa
authors: Y
authors: Isa
authors: Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang 453002, China; Key Laboratory of High-efficient and Safe Utilization of Agriculture Water Resources of Chinese Academy of Agricultural Sciences, Xinxiang 453002, China.
authors: Yuan
authors: Y
authors: Liu
mesh_terms: D001682:Biological Availability; D002104:Cadmium / Q000032:analysis / Q000493:pharmacokinetics; D002606:Charcoal / Q000494:pharmacology; D003545:Cysteine / Q000378:metabolism; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005978:Glutathione / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D018527:Hydroponics; D054811:Phytochelatins / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects; D018520:Plant Shoots / Q000187:drug effects; D058441:Rhizosphere; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000493:pharmacokinetics; D032323:Solanum melongena / Q000254:growth & development* / Q000378:metabolism
chemical_list: D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002104:Cadmium; D002606:Charcoal; D054811:Phytochelatins; D005978:Glutathione; D003545:Cysteine
keywords: Biochar; Cd; Phytochelatin synthase activity; Root morphology; Seedling culture