中文摘要：

采用水培法，用一定浓度的Hg^2＋和不同浓度的萝卜过氧化物酶（RsPrx）对小麦进行浸种处理后，对小麦幼苗叶片中的过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）等同工酶的活性变化进行了研究．结果显示：在Hg^2＋胁迫下加入一定浓度外源活性POD后的小麦幼苗的叶片中的POD和SOD同工酶表达量与单独Hg^2＋胁迫处理时相比，明显减少，更接近正常对照．在Hg^2＋胁迫下加入一定浓度外源活性POD后的小麦幼苗叶片中的CAT同工酶表达量与单独Hg^2＋胁迫处理时相比明显增加，更接近正常对照．POD，CAT和SOD同工酶的表达量都有明显变化，但其谱带的数目没有发生明显变化．由此推测，一定浓度外源活性POD对Hg^2＋胁迫下的小麦幼苗的早期生长和发育可以起到一定的缓解作用．

英文摘要：

The seeds of wheat are soaked in given concentrations of Hg^2＋ and a series of concentrations of external peroxidase （RsPrx）, then the isoenzyme activities of peroxidase（POD）, catalase（CAT） and superoxide dismutase（SOD） in leaves of wheat seedlings are studied by water culture method. The results show that the isoenzyme activities of POD and SOD in leav es under Hg^2＋ stress and some concentrations of POD decrease obviously compared with those under Hg^2＋ stress alone, close to the normal control. The isoenzyme activities of CAT in leaves under Hg^2＋ stress and POD increase obviously compared with those under Hg^2＋ stress alone, close to the normal control. The isoenzyme activities of POD, CAT and SOD change obviously, but the numbers of the isoenzyme bands have not changed almost. All in all, certain concentrations of external radish peroxi- dase play an important role of attenuating the growth and development of wheat in early stage under Hg^2＋ stress.