茶树对铅、镉、铜的吸收累积特性研究

为了解茶树对Pb、Cd、Cu的吸收累积规律,在具有不同土壤铅(Pb)、镉(Cd)、铜(Cu)背景值的5个茶园,分析了同一茶园5个茶树品种和5个不同生境茶园福鼎大白茶(Camellia sinensis cv.Fuding-dabaicha)种群的土壤和侧根Pb、Cd、Cu的含量,以及相应5个品种及5个种群的老嫩叶Pb、Cd、Cu的含量、富集系数和转移系数.结果表明:①同一生境下5个茶树品种体内Pb、Cd、Cu含量分布次序为侧根＞老叶＞嫩叶,品种间Pb、Cd、Cu含量存在一定差异.②同一生境下5个茶树品种老叶、嫩叶Pb、Cd、Cu富集系数和转移系数差异显著,Pb的富集系数分别为0.12 ～0.18和0.09～0.11；Cd富集系数分别为1.59～2.97和0.72 ～1.31；Cu转移系数分别为0.32 ～0.41和0.20 ～0.28.③不同生境下福鼎大白茶种群的Pb、Cd、Cu含量也存在差异,MT种群嫩叶Pb、Cd含量分别为3.46和0.37 mg/kg,高于有机生态茶园XRL种群嫩叶中Pb、Cd的含量(1.50、0.07 mg/kg)；土壤理化性质与茶树Pb、Cd、Cu的含量具有一定相关性；洗涤前和洗涤后的茶叶重金属含量差异较大,福鼎大白茶老叶洗涤前Pb含量为8.59 mg/kg,洗涤后为5.13 mg/kg.同一生境下的不同茶树品种受遗传作用控制,对Pb、Cd、Cu的吸收累积能力有一定差异；不同生境下的福鼎大白茶种群由于受环境的影响,侧根及老嫩叶Pb、Cd、Cu的含量也存在明显差异.

Study on Uptake and Accumulation of Pb, Cd and Cu in Tea Plant

Five tea cultivars were sampled from the same site and five Camellia sinensis cv.Fuding-dabaicha populations from five different sites with different background concentrations of soil Pb,Cd,Cu,Pb,Cd, Cu contents in soils,and Pb,Cd,Cu concentrations,accumulation and transfer coefficients in old and young leaves were analyzed to investigate characteristics of lead(Pb),cadmium(Cd) and copper(Cu) uptake and accumulation in tea plant.The results showed that:(i) Under the same habitat,distribution order of Pb,Cd,...