四季竹对大气臭氧体积分数倍增的生理响应

Physiological responses of Oligostachyum lubricum with elevated atmospheric ozone concentrations

为了给气候变化背景下的竹林培育应对策略提供理论依据,以四季竹Oligostachyum lubricum为材料,运用开顶式气室(OTCs)模拟当前环境背景大气臭氧(O3)体积分数(NF,40～45 nL.L-1)倍增1倍(TR-1,92～106 nL.L-1)和倍增2倍(TR-2,142～160 nL.L-1)情景,分析叶片光合色素、可溶性蛋白、可溶性糖和脂质过氧化及抗氧化酶等生理指标的变化。结果表明:大气臭氧体积分数倍增90 d时,与NF比较,TR-1和TR-2处理的四季竹叶片叶绿素、类胡萝卜素、可溶性蛋白和超氧化物歧化酶(SOD)活性均显著降低,而叶片相对电导率、丙二醛(MDA)和过氧化物酶(POD)活性均显著升高,而叶片可溶性糖仅TR-2较NF显著下降;叶片相对电导率和丙二醛TR-2显著高于TR-1,而叶片可溶性糖TR-2显著低于TR-1。说明大气臭氧体积分数倍增能引起四季竹叶片细胞膜脂过氧化,膜结构遭到破坏,影响四季竹的正常生长,表现出伤害效应。

This research was conducted to provide theoretical evidence for bamboo cultivation during this time of possible climate change.Open-top chambers（OTCs） were employed to determine the effects of elevated ozone on photosynthetic pigment content,soluble protein content,soluble sugar content,lipid peroxidation,and anti-oxidation enzymes in the leaves of Oligostachyum lubricum using a split-plot design with treatments of Control（NF）,92-106 nL·L-1 of O3 concentration（TR-1）,and 142-160 nL·L-1 of O3 concentration（TR-2）,three replications.Results showed that,after 90 d,compared with NF,in treatments TR-1 and TR-2 there were significant decreases in the contents of chlorophyll（P = 0.002 4）,carotenoids（P = 0.049 4）,and soluble protein（P = 0.031 5）,as well as superoxide dismutase（SOD） activity（P = 0.033 0） with significant increases in relative electrical conductivity（P = 0.013 5）,peroxidase（POD） activity（P = 0.039 6）,and malondialdehyde（MDA） content（P = 0.000 4）.Soluble sugar content decreased significantly（P = 0.003 7） only in treatment TR-2.Also,in leaves of TR-2 compared to TR-1,there was a significant increase in electrical conductivity（P = 0.044 8） and MDA content（P = 0.000 2）,but a significant decrease in soluble sugar content（P = 0.001 5）.Thus,elevated ozone concentrations intensified the damage to membrane lipids and destroyed the structure of cell membranes,thereby affecting normal growth of O.lubricum.