关键词: 进化, 特化, 概念

Abstract: With pot experiment, this paper studied the effects of PCBs (0, 180, 900, 1 800 and 2 700 μg·kg^-1) on the seedlings growth and the leaves chlorophyll content, MDA content, and membrane protective enzyme system of Aegiceras corniculatum. The results showed that PCBs had definite stimulative effects on the seedlings growth. The stem height, basal stem diameter, and stem volume were all increased with increasing PCBs concentration. Within the test range of PCBs, the chlorophyll content and chlorophyll a/b ratio maintained at a relatively stable and normal level. The decrement of chlorophyll content and the increment of chlorophyll a/b ratio were less than 25% and 10% of the control, respectively. With increasing PCBs concentration, SOD activity increased first and decreased then,while POD activity and MDA content were in adverse. It was suggested that A.corniculatum could endure and adapt definite concentrations of PCBs through physiological and biochemical mechanisms, being available to the phytoremediation of PCBs pollution.

Key words: Evolution, Specialization, Concept