O3浓度升高和UV-B辐射增强对大豆叶片叶绿素含量和活性氧代谢的影响

以大豆栽培品种铁丰29为试验材料，利用开顶式气室研究O₃浓度升高和UV B辐射增强复合胁迫对大豆叶片叶绿素(Chl)含量、膜脂过氧化程度、活性氧产生速率、抗氧化酶活性和籽粒产量的影响.结果表明： 在大豆整个生育期内，与对照相比，O₃和UV-B单一胁迫及其复合胁迫下的大豆叶片Chl(a+b)、Chl a和Chl b含量均呈下降趋势；相对电导率、丙二醛含量增大，活性氧产生速率和H₂O₂含量增加，超氧化物歧化酶、过氧化物酶和过氧化氢酶活性下降，产量降低.O₃和UV-B复合胁迫加剧了大豆叶片膜脂过氧化程度，促进大豆体内活性氧自由基的产生，使大豆抗氧化能力减弱，叶绿素含量降低，对大豆表现为协同效应.O₃胁迫对大豆叶片的影响与复合胁迫更相近，其原因可能是在复合胁迫中臭氧起主要作用.

Behaviors of Pére David's deer harem master during its rutting period in Shishou County of Hubei Province, China

Taking the soybean (Glycine max) cultivar Tiefeng 29 as test material, and by using open0top chamber, this paper studied the effects of elevated O₃ concentration and UV B radiation on the leaf chlorophyll content, lipid peroxidation, reactive oxygen species (ROS) production rate, anti oxidation enzymes activities, and the grain yield. During the growth period of soybean, as compared with the control, the leaf Chl a, Chl b and Chl(a+b) contents under the stresses of O₃ and UV-B had a decreasing trend, the relative electrical conductivity, malondialdehyde content, superoxide anion (O₂^-·) production rate, and hydrogen peroxide (H₂O₂) content increased, and the activities of superoxide dismutase, peroxidase and catalase as well as the grain yield decreased. O₃+UV stress aggravated the leaf membrane lipid peroxidation, promoted the ROS production, and decreased the plant antioxidant capacity and leaf chlorophyll content. The negative effects of O₃ stress on soybean leaves were more close to the impacts of O₃+UV-stress, suggesting that O₃ might play an important role in the combined stress.