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作 者 ：应蓉蓉¹;杜锁军¹;胡鹏杰¹;赵芝灏¹;周小勇¹;汤叶涛¹;仇荣亮^1,2

期 刊 ：应用生态学报 2008年 19卷 06期 页码：1349-1354

关键词：长柔毛委陵菜；

摘 要 ：采用水培方法研究了不同Zn处理水平和处理时间下长柔毛委陵菜对锌的吸收动力学特性. 结
果表明，在10 mg·L^-1 Zn处理下，植株地上部和根系的Zn含量均在第8天达到最高
值，分别为2.49×10³ mg·kg^-1和2.21×10³ mg·kg^-1；在100 mg·L^-1 Zn处理下，植株地上部的Zn含量在第16天达最高值1.23×10³ mg·kg^-1，而根系Zn含量不存在饱和现象. 在0～160 mg·L^-1 Zn处理下，植株叶片和叶柄Zn含量随Zn处理水平的提高显著增加，Zn浓度大于160 mg·L^-1后, 植株叶片和叶柄Zn含量不再随介质中Zn浓度的提高而增加（甚至减少）, 根系含Zn含量与介质中的Zn浓度和培养时间呈正相关，且根系Zn吸收动力学曲线具有二型性，即开始为快速的线性吸收，随后是较缓慢的饱和吸收，两者分界点约在1～2 h，这可能分别与根细胞壁吸附Zn和Zn跨根细胞膜运输有关.

Abstract:

The kinetic characteristics of Zn uptake by Potentilla griffithii Hook. f. var. velutina Card. were studied with hydroponic culture under differen
t Zn supply and its exposure time. When the Zn supply was 10 mg·L^-1, the
Zn concentration in shoot and root reached the peak on the 8^th day, being

2.49×10³ mg·kg^-1 and 2.21×10³ mg·kg^-1, respectively; while when
the supply was 100 mg·L^-1, the Zn concentration in shoot reached the max
imum (1.23×10³ mg·kg^-1) on the 16^th day, but that in root did not exhibit saturation. The Zn concentration in leaf and leafstalk increased with increasing Zn supply from 0 to 160 mg·L^-1, but had no increase or even decreased when the Zn supply was higher than 160 mg·L^-1. The Zn concentration in root exhibited a positive correlation with Zn supply and its exposure
time, and the kinetic curve of Zn uptake fitted linear-quadratic (LQ) model,
i.e., fast linear uptake first and slow saturation uptake later, with the d
ividing point at about 1.2 hours’ exposure, which could be related with the Zn
adsorption on root cell wall and the Zn transportation across the cell memb
rane.

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