大花蕙兰“黄金小神童”和燕子掌对不同浓度苯气长期熏蒸的耐性

Tolerance of Cymbidium Golden Elf and Crassula portulacea to different concentrations of benzene fumigation

环境污染的植物修复技术因其低廉环保而备受关注,盆栽植物在净化室内空气苯污染物中发挥着重要作用,对苯净化效果好的植物类型又具有较强的耐污能力时才可获得广泛应用.本研究旨在探讨2种苯净化效果好的植物大花蕙兰"黄金小神童"(Cymbidium Golden Elf)和燕子掌(Crassula portulacea)在长期苯气污染状态下的生理和抗氧化系统反应特征,确定它们对苯气污染物的抗性能力.对两种植物进行45 d的苯气浓度梯度(0,150,300 ppb,1 ppb=1 g/L)动态熏蒸实验,测定生理和抗氧化系统等14种参数发现,2种植物对苯熏蒸均具有较好的耐性,它们的生理参数和抗氧化系统具有各自的先天优势,且苯气熏蒸对这种优势无明显影响.相关性分析显示在清除体内H2O2时,大花蕙兰"黄金小神童"的CAT和燕子掌的AsA功不可没.另外,SOD在防止两种受试植物的膜脂过氧化方面均发挥重要作用,对燕子掌而言,AsA作用更强.

Phytoremediation has been studied extensively because of its low cost and environmentally friendly features in controlling environmental pollution. Potted plants play an important role in purifying indoor air from benzene pollutants. The plant species with ideal pollutant-removal ability could be applied widely; however this can only be done once the plants are also highly tolerant of the pollutants. This research investigates the physiological and anti-oxidant system adaptations of two benzene-removing plant species(Cymbidium Golden Elf and Crassula portulacea) in a prolonged benzene fumigation state. The fumigation lasted for 45 d with three treatments of 0,150 and 300 ppb of benzene. The measurement of the physiological and anti-oxidant adaptations showed that the two species tolerate benzene well. These adaptations had their own inherent advantages in each species and could prevent damage to the plant from the benzene fumigation. Correlation analysis suggests that catalase in Cymbidium Golden Elf and ascorbic acid(AsA) in Crassula portulacea contribute to the removal of peroxide from the plants. In addition,superoxide dismutase plays an important role in the prevention of membrane lipid peroxidation in both test plants; however,in Crassula portulacea the role of AsA is stronger.