不同浓度镉对黄花蒿生物量、青蒿素的含量及相关酶基因表达的影响

Effects of different concentrations of cadmium on biomass, artemisinin content and genes expression in Artemisia annua L.

目的:研究不同浓度重金属镉对黄花蒿生长、次生代谢产物以及相关酶基因表达的影响。方法:通过在水培液中添加不同浓度镉的方法胁迫处理黄花蒿,并于处理后不同时间检测与植物生长相关的各项指标,同时收集叶片和全植株用于青蒿素含量测定及关键酶基因表达分析。结果:黄花蒿的地上鲜重、地下鲜重、株高、茎粗和叶片数均在较低浓度镉处理组中(20和40μmol/L)达到最大值;重金属镉能够促进青蒿素的合成,同时青蒿素累积量受镉浓度和处理时间双重因素的影响;在120μmol/L镉处理组中,ADS、CYP71AV1和ALDH1的表达量均明显高于对照组(P<0.05)。结论:低浓度镉表现出促进黄花蒿的生长,且适当浓度镉处理黄花蒿一定时间后可能会通过上调青蒿素合成途径上关键酶基因的表达来提高青蒿素的积累。

Objective： To observe effects of different concentrations of cadmium（Cd） on biomass, artemisinin content and genes expression in Artemisia annua L.. Methods： Artemisia.annua L. was cultured in controlled hydroponic environment with different concentrations of Cd, and indexes related to plant growth were detected at different times after treatment. Meanwhile, leaves and whole plants were collected to determine artemisinin content and expression of key enzyme genes. Results： The results showed that： aboveground and underground fresh weight, plant height, stem diameter, and number of leaves of Artemisia.annua L. reached the maximum value in treatment groups with lower Cd concentrations（20 and 40 μmol/L）; Cd promoted synthesis of artemisinin, and artemisinin accumulation was affected by both Cd concentrations and treatment time; the expression of ADS, CYP71AV1 and ALDH1-key enzyme genes of artemisinin synthesis in 120μmol/L treatment group were significantly higher than those of control group（P〈0.05）. Conclusion： It demonstrated that lower concentration of Cd could promote growth of Artemisia.annua L.. Appropriate doses of Cd could increase concentration of artemisinic at a certain time by up-regulating expression of key genes related to artemisinin biosynthesis.