镉胁迫下硅对高粱生长的影响及其作用机制  

The Effect and Mechanism of Silicon on Sorghum Seedlings Growth Under Cadmium Stress

作　　者：刘朋[1] 殷俐娜[1,2] 王仕稳[1,2] 邓西平[1,2] 

机构地区：[1]中国科学院水利部水土保持研究所,黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西杨凌712100 [2]西北农林科技大学水土保持研究所,陕西杨凌712100

出　　处：《水土保持研究》2014年第6期329-333,共5页Research of Soil and Water Conservation

基　　金：国家自然科学基金(31101597);教育部高校基本科研业务费(QN2012048)

摘　　要：尽管硅提高植物的抗镉毒害已经被广泛的报道,但是其作用机理还不明确。该试验研究在镉胁迫的条件下,硅对高粱生长的影响及作用机制。结果发现:外源施加硅能显著地缓解镉对高粱无论地上部分还是地下部分鲜重及干重的抑制作用。抗氧化酶结果表明:在正常条件下,硅对抗氧化酶的活性没有显著的影响。在镉毒害的条件下,硅显著增强CAT和POD的活性,SOD的活性不受影响。与此相对应:硅显著地降低MDA的含量。对有机酸的分析发现:在镉胁迫的条件下,叶片中有3种有机酸能够检测到:草酸,丙二酸,丁二酸,并且其含量都在硅的调节下增加。而在根系中所检测的4种有机酸中,草酸和丙二酸的含量受到硅的调节而增加,柠檬酸的含量不受影响,而苹果酸的含量却有下降的趋势。上述结果表明:硅增强高粱幼苗的抗镉胁迫与其增强高粱抗氧化酶活性及增加高粱体内有机酸的含量相关。Although the effects of silicon on cadmium resistance are wildly reported, the underlying mecha- nism is still unclear. In the present study, we investigated the effect and mechanism of silicon on sorghum seedling growth under cadmium stress. The result indicated silicon application alleviated cadmium-induced decrease in fresh weight and dry weight both of shoot and root. The result indicated that the anti-oxidant en- zyme activity was not affected by silicon under control condition. However under cadmium stress, the CAT and POD activity were significantly increased by silicon. The SOD activity was not influenced by silicon. Corresponding to this result, MDA was decreased by silicon. The result indicated that 3 types of organic acids （OA） including oxalic acid, propanedioic acid and succinic acid were detected in leaf. All of them were increased by silicon under cadmium stress. In the root, 4 types of OA such as oxalic acid, malic acid, pro- panedioic acid and citric acid were detected. Oxalic acid and propanedioic acid contents were increased by sili- con. Citric Acid content was not influenced by silicon. However, the malic acid was decreased by silicon. All of the results indicated that the enhancement of anti-oxidant enzyme activity and OA content involved in the silicon-induced sorghum seedlings cadmium resistance.

关 键 词：硅 镉 抗氧化酶 有机酸 

分 类 号：Q945.78[生物学—植物学]