稀土在玉米及水稻中吸收分布与积累规律研究

UPTAKE,DISTRIBUTION AND ACCUMULATION OF RARE EARTH ELEMENTS IN MAIZE AND PADDY RICE PLANTS

研究玉米和水稻中 5个稀土元素 (La ,Ce ,Nd ,Y ,Gd)的含量分布以及单一稀土的分布规律。结果表明 :玉米和水稻吸收稀土的能力与土壤可给性稀土呈正相关关系 ,植物体各部位稀土含量分布一般规律为根 >叶 >茎 >果实 ;单一稀土在根部的分布特征是La >Ce >Nd >Y >Gd ,在叶、茎、果实的分布特征是Ce >La>Nd>Y >Gd ,说明轻稀土较重稀土易被植物吸收。总之 ,稀土元素在植物中不易迁移 ,主要集中在根部 ,果实中含量甚微 ,因而施用稀土微肥 ,不会影响食用粮食的安全问题。

A pot experiment was made with maize and paddy rice in which five rare earths were applied as fertilizers.The ability of the plants to take up La,Ce Nd,Y and Gd was shown to be positively correlated with the available rare earths in the soil.Their concentration was greatest in the roots,followed in order by the leaves,the stem and the seeds.Individual rare earth elements accumulated appeared in the following order:La>Ce>Nd>Y>Gd in the roots and in the order:Ce>La>Nd>Y>Gd in the leaves,the stem and in the seeds.Such results suggest that light rare earths are more readily absorbed by maize and rice plants than heavy rare earths and that rare earths are hardly movable in plants.It is thus concluded that rare earths can be applied to grain crops without the hazard of affecting their quality.