摘要： 以紫花苜蓿为试材,采用盆栽试验,研究不同浓度Cd2+胁迫对不同茬期紫花苜蓿的叶绿素、可溶性糖的影响。结果表明:随重金属Cd2+胁迫剂量的加大,3茬紫花苜蓿叶绿素含量、可溶性糖含量呈倒"N"形规律变化,即降-升-降的变化,这与重金属诱导下紫花苜蓿的防御机制有关。3茬紫花苜蓿的可溶性糖含量不同,依次是第1茬>第2茬>第3茬,3茬紫花苜蓿的叶绿素含量不同:低浓度Cd2+下,第2茬>第1茬>第3茬;高浓度Cd2+下,第2茬>第3茬>第1茬。主要原因可能是由于苜蓿的收割,导致Cd流失,胁迫作用减弱或者是多种影响因素综合作用的结果。

关键词: Cd2+胁迫, 紫花苜蓿, 叶绿素, 可溶性糖, 防御机制

Abstract: With alfalfa as a testing plant growing in pots of Cd-contaminated soil, the effect of chlorophyll and solublesugar of different stubble is studied with Cd²⁺ stress in different doses. The result shows that the contents of chlorophylland soluble sugar change as converse'N' with heavy metal doses increasing, viz. as the rule of falling-rising-falling. Thisstress mechanism may be related with recovery system of alfalfa because of heavy metal inducing.The contents of solublesugar of three stubbles are different, as follows: the first stubble> the second stubble> the third stubble. On the otherhand, the contents of chlorophyll of three stubbles are different, as follows: the second stubble> the first stubble> thethird stubble at low concentration; the second stubble> the third stubble> the first stubble at high concentrat ion. Themajor reason of the result either may be lost Cd and weakened stress because alfalfa is reaped, or may be mult-i factor actone another.

Key words: Cadmium stress, Alfalfa, Chlorophyll, Soluble sugar, Recovery mechanism

中图分类号: 

• S541.9