【摘 要】
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There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first use
【机 构】
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Department of Chemical and Biological Science
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There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on microstructure, most reports are focused on the toxicology rather than promotion. Using cucumis sativus L. (Jin Chun No.5) as experiment material, we try to find out the nutritional effects of low Y3+ concentrations on cucumber seedlings' leaves. The present paper suggests that the rare earth elements act as micronutrients at low concentrations while they give rise to toxicity at high concentration. Benefits defeat toxicity with concentration ranging from 5 to 25μmol·L-1. Through careful study, at the Y (N03)3 concentration of 10μmol·L1 the content of chlorophyll as well as the activities of SOD, Cu-Zn SOD and the POD are the highest. It indicates 10μmol·L-1 is the optimum concentration of yttrium for promoting the cucumber growth.
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