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作 者 ：黄化刚^1,2;李廷轩¹;张锡洲¹;田生科²;杨肖娥²

期 刊 ：应用生态学报 2008年 19卷 04期 页码：831-837

关键词：东南景天；

摘 要 ：采用水培试验，研究了外源添加不同浓度钙离子（Ca²⁺）对两种生态型东南景天生物量、根系形态及体内锌、钙、硫含量的影响.结果表明：随着外源Ca²⁺浓度的上升，两种生态型东南景天的干物质量均增加，且超积累生态型地上部增加显著(P<0.05)；超积累生态型根长和根表面积增加，而非超积累生态型降低；超积累生态型根、茎、叶锌含量随着外源Ca²⁺浓度的增加而上升，但各处理间差异不显著(P>0.05)，非超积累生态型地上部锌含量显著降低(P<0.05).非超积累生态型根、茎、叶钙含量与外源Ca²⁺浓度呈显著正相关(P<0.05)，超积累生态型根系硫含量与外源Ca²⁺浓度呈极显著正相关(P<0.01).外源Ca²⁺对超积累生态型东南景天锌吸收及积累有促进作用，而Ca²⁺浓度的升高抑制了非超积累生态型东南景天对锌的吸收.适当增加外源Ca²⁺可促进超积累生态型东南景天生长，改善其锌积累能力.

Abstract:

A hydroponic study was conducted to investigate the biomass, root morphology, and zinc (Zn), calcium (Ca) and sulfur (S) contents of two Sedum alfredii- ecotypes under effects of different concentration calcium (Ca²⁺) addition. The results showed that with increasing exogenous Ca²⁺ concentration, the dry mass of the two S. alfrediiecotypes increased, and the shoot dry mass of hyperaccumulation ecotype increased significantly (P<0.05). The root length and root surface area of hyperaccumulation ecotype increased with increasing exogenous Ca²⁺ concentration, while those of nonhyperaccumulation ecotype were in adverse. The Zn accumulation in the root, stem and leaf of hyperaccumulation ecotype was increased with increasing exogenous Ca²⁺ concentration though the differences among Ca²⁺ treatments were not significant (P>0.05), while the Zn accumulation in the shoot of nonhyperaccumulation ecotype was significantly low (P<0.05). The Ca accumulation in the root, stem and leaf of non-hyperaccumulation ecotype had a significant positive correlation with the concentration of exogenous Ca²⁺ (P<0.05), so as the S accumulation in the root of hyperaccumulation ecotype (P<0.01). Exogenous Ca²⁺ promoted the Zn absorption and accumulation of hyperaccumulation ecotype, while inhibited the Zn accumulation of nonhyperaccumulation ecotype. Appropriate concentration of exogenous Ca²⁺ could promote the growth of hyperaccumulation ecotype S. alfredii, and improve its ability of accumulating more zinc.

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