不同栽培介质中铅、镉在茭白产品中残留的差异

[目的]为茭白的卫生安全生产提供参考依据。[方法]以单季茭品种"蒋墅茭"和双季茭品种"葑红早"为试材,以苇末和土壤为栽培基质进行不同浓度Cd2+、Pb2+胁迫处理,测定不同采收标准的产品器官中Cd2+、Pb2+残留量的变化。[结果]茭白产品器官对Cd2+、Pb2+的最高生物富集系数分别为0.340%和0.044%。过老发绿的肉质茎中,Cd2+、Pb2+的残留量最高,中等大小的肉质茎中残留量最低,且随重金属胁迫浓度的增加而显著增加。苇末基质栽培的茭白肉质茎中Cd2+、Pb2+的残留量均显著低于土壤栽培的。"葑红早"产品器官中Cd2+的残留量高于"蒋墅茭",Pb2+的残留量则相反。[结论]苇末栽培基质有利于降低重金属离子在茭白产品中的残留量。

Difference on Pb2 and Cd2 Residue in Zizania latifolia Products on Different Cultivation Media

[Objective] The study aimed to provide reference foundation for the healthy and safe production of Zizania latifolia.[Method] With single-harvested variety "Jiangshujiao" and double-harvested variety "Fenghongzao" of Z.latifolia as tested materials,the stress treatments with different concn.of Cd2 and Pb2 were conducted with reed residue and soil as cultivation substrates.The changes of Cd2 and Pb2 residues in the product organs at different harvest standards were determined.[Result] The highest biological enrichment coefficients on Cd2 and Pb2 of Z.latifolia product organs were 0.340% and 0.044% resp.The Cd2 and Pb2 residues were highest in too-old and green fleshy stem and lowest in the fleshy stem of middle size and significantly increased along with the increment of stress concn.of heavy metal.The Cd2 and Pb2 residues in the fleshy stem of Z.latifolia cultivated on reed residue were significantly lower than that on soil.The Cd2 residue in the product organs of "Fenghongzao" was higher than that of "Jiangshujiao" and the Pb2 residue was opposite.[Conclusion] Reed residue was in favor of decreasing the residues of heavy metal ions in Z.latifolia products.