关键词: 铝毒胁迫, 柠檬酸, 分泌与累积

Abstract: By the method of solution culture, this paper studied the coercion and damage of Cu pollution on the growth of Artemisia lavandulaefolia. The Cu concentration was set as 2.5, 5, 10, 20 and 40 mg·L^-1, experimental duration was 14 days, and the growth and physiological indices of plants were tested. The results showed that the growth of A. lavandulaefolia was stimulated at low Cu concentration (2.5 mg·L^-1), while inhibited at higher Cu concentrations (5～40 mg·L^-1). There was a significant negative correlation between each growth index and Cu concentration, and pigments contents had the similar trend. The sensibility of various photosynthetic pigments to Cu was in the order of chlorophyll a＞chlorophyll a+b＞chlorophyll b＞carotenoid. Cell membrane permeability, O₂^-· generation rate, and MDA content decreased slightly at 2.5 mg Cu ·L^-1, and then increased with increasing Cu concentration. The activities of POD, SOD and CAT increased first but decreased then with the increasing Cu concentration, and the endurance index of root showed the same trend, being ＞0.5 at the Cu concentration less than 20 mg·L^-1 while decreased to 0.36 at 40 mg Cu·L^-1.

Key words: Al toxicity stress, Citric acid, Exudation and accumulation