摘要:为了研究N+注入对蒙古黄芪多倍体生化指标的影响,采用培养基中添加秋水仙素的方法诱导多倍体,测定不同剂量N+注入的情况下,不同诱导时间内分化出的不定芽及二倍体和四倍体植株叶片的生化指标变化情况.结果表明:未注入组丙二醛(malonaldehyde,MDA)的含量,以及过氧化物酶( peroxidase,POD)、过氧化氢酶(catalase,CAT)和超氧化物歧化酶(superoxide dismutase,SOD)的活性,随诱导时间的延长而增高,蛋白质含量随诱导时间的延长而降低,蛋白质含量与MDA含量呈负相关;注入组的生化指标在诱导时间内都有一定的波动,但总体趋势与未注入组一致;四倍体与二倍体相比较,四倍体的MDA含量及POD、CAT和SOD的活性都高于二倍体,而蛋白质含量却低于二倍体.说明离子束注入能使种子产生大量自由基,自由基的增加可导致MDA的产生,从而破坏蛋白质的合成,同时,N+注入又可诱发新的修复机制;四倍体植株受伤害程度更大,但四倍体植株的自我保护能力高于二倍体植株,即四倍体植株的抗逆性较二倍体增强.%To study effects of N+ implantation on biochemical indexes of polyploid Astragalus membranaceus, colchicine was added into medium to induce polyploidy. By measuring the biochemical indexes of adventitious buds at different induction times and leaves from tetraploid and diploid plants, data showed that malondialdehyde (MDA) content, and peroxidase (POD), catalase (CAT), superoxide dismutase (SOD) activities were positively correlated with induction time, but protein content was negatively correlated with induction time in control group. The biochemical indexes of treated group showed fluctuations during induction. MDA content and POD, CAT, SOD activities in tetraploids were higher than in diploids, while protein content in tetraploids was lower than in diploids. These data indicated that abundant free radicals were produced by N+ implantation, leading to MDA generation and inhibition of protein synthesis. Ion implantation also induced new repair mechanisms, tetraploid plants showed greater degree of injury, but self-protection and stress resistance in tetraploid plants were higher than in diploid plants.