伊乐藻对水体磷浓度的生理响应

Physiogical Responses of Elodea Nuttallii to Phosphorus Concentrations

为探究不同磷浓度下伊乐藻的生理及生长特征,采用静态模拟试验,通过对伊乐藻生物量和抗氧化防御系统等指标的测定及不同组织亚细胞结构变化的观察,研究伊乐藻对磷浓度的响应。结果表明,在氮浓度为0.20 mg/L培养14 d时,伊乐藻对≥0.05 mg/L的磷浓度表现出明显胁迫反应;综合SOD、ASA和MDA等数据分析结果得出,在试验周期内,伊乐藻对≤0.80 mg/L的磷胁迫可以通过自身抗氧化系统进行调节修复;当磷浓度达1.60 mg/L时,随着胁迫时间延长,伊乐藻体内的抗氧化系统遭到破坏,使植株失去自我调节修复能力,内在表现为伊乐藻根、茎、叶组织中线粒体、叶绿体等亚细胞结构的完整性遭到破坏。

The physiological and growth characteristics of submerged plant Elodea nuttallii at different phosphorus concentrations were studied in a static simulation experiment by measuring the biomass, antioxidant defense system and the changes in subcellular structure of different tissues. The results revealed that under 0.20 mg/L nitrogen concentration, Elodea nuttallii demonstrated a significant stress response to phosphorus concentrations level greater than 0.05 mg/L in 14 days. Comprehen-sive analysis of SOD, ASA and MDA and other data, during the experimental period, showed that the phosphorus concentra-tion stress less than 0.80 mg/L can be adjusted through its antioxidant system. As the extension of stress time, when the phos-phorus concentration was more than 1.60 mg/L, Elodea nuttallii antioxidant system was destroyed, because the plants lost their adjusting ability to repair, inside the root, stem and leaf tissues such as mitochondria, chloroplasts and the structural in-tegrity of cells were damaged.