水杨酸对铅镉复合胁迫下芥菜子叶生理代谢的影响

以‘福州宽杆’芥菜为试验材料,以铅、镉为变量,试验采用单因素随机设计,设8个处理,每个处理3个重复,通过种子萌发试验来探讨水杨酸在铅镉复合胁迫下对芥菜生理代谢的缓解效果.结果表明:芥菜子叶可溶性蛋白含量随铅镉复合胁迫的加剧呈先增后减的趋势,可溶性糖含量、POD活性和CAT活性显著减小,MDA、脯氨酸含量、氧负离子(O2-)产生速率和SOD活性显著提高.0.05mmol/L水杨酸浸种可显著提高铅镉复合胁迫下芥菜子叶可溶性蛋白质、可溶性糖的含量及POD和CAT的活性,其增幅分别为52.34%～148.93%、46.31%～99.66%、5.17%～15.13%、16.18%～61.57%;同时降低了芥菜子叶MDA含量、脯氨酸含量及O2-产生速率,其降幅分别为7.04%～31.80%、29.14%～40.23%、49.04%～63.79%.研究说明,添加一定浓度的水杨酸能缓解铅镉复合胁迫所导致的生理伤害.

Effects of salicylic acid on physiological metabolism of Brassica juncea under combined Pb and Cd stress

Taken the seed of Brassica juncea as material,lead and cadmium as variable value,seed germination experiment with eight treatments were designed,the effects of salicylic acid on some physiological metabolism of Brassica juncea under combined Pb and Cd stress were studied.The results showed as follows:Under combined Pb and Cd stress,the protein content of Brassica juncea cotyledon increased first and then decreased,the content of soluble sugar,POD activity and CAT activity decreased sharply,MDA,proline content,O-2 producing rate and SOD activity increased rapidly.SA soaking could enhance the protein,soluble sugar,POD and CAT activity of Brassica juncea cotyledon under combined Pb and Cd stress,their increasing ranges were 52.34%~148.93%,46.31%~99.66%,5.17%~15.13% and 16.18%~61.57% respectively,while it decreased the MDA content,proline content and O-2 producing rate,the decreasing ranges were 7.04%~31.80%,29.14%~40.23% and 49.04%~63.79% respectively.The experiment showed that salicylic acid could relief some physiological metabolism of Brassica juncea and the damage made by active oxygen under combined Pb and Cd stress.