模拟重金属污染下曼陀罗种群核酸代谢变化研究

Dynamic changes of nucleic acid metabolism of Datura stramonium L. under simulated heavy-metal pollution

将不同空间地段上获得同一种质但污染年代各不相同的曼陀罗材料种子易地种植在同一模拟重金属污染生境中生长 ,对比分析了曼陀罗种群的核酸代谢 (DNA、RNA、DNase、RNase)动态变化 .结果表明 :在本实验条件下 ,种群的核酸代谢发生了定向性改变 ;在短期污染条件下 ,DNA、RNA、DNase、RNase活性代谢发生了一定程度的紊乱 ,随着污染时间的推移 ,上述生理变化逐渐向对照CK种群的“正常值”回复 ,表现出种群对重金属污染迹地的抗性适应和分化 ,且分化发生的速度远高于植物自然分化进程 .根据上述四项生理指标对这四个曼陀罗种群利用模糊数学评判分析方法进行排序 ,适应性从优到劣的排序顺序为CK >L >M >S .

Based on the same original genetically germ plasm, different Datura stramonium L. (abbreviated as D.S. in context) populations were obtained. The control population was named CK, the short termed S, the medium termed M, and the long termed L. The seeds from the three D.S. populations (S, M, and L) were respectively planted in the same simulated heavy metal polluted soil. The seeds from CK were planted in normal soil. The dynamic change of nucleic acid metabolism of D.S. (DNA, RNA, DNase, RNase) was analysed in the course of the D.S. populations growing. The results could be concluded as follows:Heavy metal pollution could reduce the nucleic acid contents and enhance the activities of DNase and RNase of S and M populations. On the other hand, with pollution years prolonging, the longer duration polluted population tended to restore to the original (CK population); L population had basically adapted to the polluted environment. According to ordination of Fuzzy Mathematics Analysis Method through above the four phsiological indexes, the ordination result was CK>L>M>S in order of excellentance. It was suggested that D.S. population obtained directional changing for adaptation differentiation and micro evolution to resistance on condition of polluted time prolonging, and pollution dramatically sped up the differentiation rate.