title: Effect of coated urea on cadmium accumulation in Oryza sativa L. grown in contaminated soil.
abstract: Experiments were conducted to determine the effects of three types of coated urea on the accumulation of cadmium (Cd) in rice (Oryza sativa L.) grown in contaminated soil. Pot-culture experiments were conducted in a greenhouse from July to November 2012 on the rice cultivar "Hua Hang Si Miao" in Guangzhou (China). The experimental design was completely randomized with four treatments and three replications. The treatments were control (CK) (N 0 mg/kg), prilled urea (PU) (N 200 mg/kg), polymer-coated urea (PCU) (N 200 mg/kg), and sulfur-coated urea (SCU) (N 200 mg/kg). Our results indicated that applications of PCU and SCU slightly increased the dry weight of rice grains. The application of SCU significantly decreased the CaCl2 and toxicity characteristic leaching procedure (TCLP)-extractable Cd concentrations by 15.4 and 56.1%, respectively. Sequential extractions showed that PCU and SCU applications led to a significant decrease in Cd in the exchangeable fraction and an increase in the bound iron (Fe) and manganese (Mn) oxides fractions. Cd concentrations in grains treated with PCU were reduced by 11.7%, whereas SCU significantly reduced Cd concentrations by 29.1%. SCU reduced Cd transfer from the straws to the grain. Our results demonstrated that PCU and SCU may be effective in mitigating Cd accumulation in rice grown in acidic Cd-contaminated soil, especially in plants receiving SCU.
authors.affiliation: Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agricultural, CAS, Changsha, 410125, China. xuchao1388@126.com.|College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. xuchao1388@126.com.|College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China. xuchao1388@126.com.
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
authors.affiliation: College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
authors.forename: Zisong
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agricultural, CAS, Changsha, 410125, China.
authors.forename: Qihong
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agricultural, CAS, Changsha, 410125, China.
authors.forename: Hanhua
authors.initials: H
authors.lastname: Zhu
authors.affiliation: College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China. Zhangyangzhu2006@163.com.
authors.forename: Yangzhu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agricultural, CAS, Changsha, 410125, China.
authors.forename: Daoyou
authors.initials: D
authors.lastname: Huang
mesh_terms: D002104:Cadmium / Q000032:analysis / Q000378:metabolism*; D002681:China; D002523:Edible Grain / Q000737:chemistry; D004784:Environmental Monitoring; D004787:Environmental Pollution; D052918:Environmental Restoration and Remediation / Q000379:methods; D007501:Iron / Q000378:metabolism; D017895:Manganese Compounds; D012275:Oryza / Q000254:growth & development / Q000378:metabolism*; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism; D014508:Urea / Q000737:chemistry*
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; C027424:manganese oxide; D013455:Sulfur; D014508:Urea; D007501:Iron
keywords: Availability; Coated urea; Contaminated soil; Heavy metal; Rice