不同水稻、菜心品种和化肥形态对作物吸收累积镉的影响

EFFECT OF CROP CULTIVARS AND CHEMICAL FERTILIZERS ON THE CADMIUM ACCUMULATION IN PLANTS

本文主要用盆栽试验研究华南地区水稻和菜心的不同品种对Ｃｄ的吸收累积以及不同形态氮、磷、钾化肥对植物吸Ｃｄ的影响。结果表明，在同一污染土壤上，汕优６３、汕优６４、二四九等水稻品种米Ｃｄ含量较高，野奥丝苗、增城丝苗、华二、五七选等品种含量较低。四九菜心１９号不论是秋植还是春植都比迟菜心２号含Ｃｄ量为低，特青菜心６０天春植时Ｃｄ浓度也明显较低。作物品种间差异可达１倍以上。不同形态氮、磷、钾化肥中，硝酸钙、碳酸氢按、钙镁磷肥、磷酸二氢钙、硫酸钾比尿素、过磷酸钙，氯化钾等更合适施用于污染土壤上。本试验也初步探讨了造成这些差异的原因。

Pot experiments were conducted to study the differences of some rice(O.Sativa)andChinese flowering cabbage(Brassica chinensis L.)cultivars on cadmiumaccumulation in plants and the effect of chemical fertilizer sources on cadmiumbioavailability. The results showed that the source of fertilizers affectedsignificantly the cadmium content in plants. Nitrogen fertilization withCa(NO3)2 and NH4HCO3 reduced the cadmium content compared with that usingNH4NO3 or CO(NH2)2, and(NH4)2SO4 resulted in and in aninverse effect. Thephosphate fertiliers decreased the cadmium content in the order: Ca-Mg-phospliate > Cd(H2PO4)2 >rock phosphate≥superphosphate.K2SO4 was preferredto KCl in ordcr to limit cadmium accumulation in plants. Among 10 ricecultivars in south China, Shanyou-63, Shanyou-64 and 249 accumulated ahigh amount of cadmium in rice grains, while that of Yeaosimiao.Zhengchengsimiao,Huaer and Wuqixuan were reiatively low.For 5 cultivars ofChinese floweringcabbage, the cadmium content in shoots decreased as follow-ing at spring crop: Teqing-60 < Teqing-80≤Chi-29<Sijiu-19≤Chi-2.At autumn crop, Sijiu-19 resulted in a higher yieldand lower cadmiumcontentthan Chi-2.The mechanisms causing these differences were preliminarilystudied.