丛枝菌根真菌对汞胁迫下水稻叶片生理和光合特性的影响  

Effects of Arbuscular Mycorrhizal fungi on Physiological and Photosynthetic Characteristics of Rice Leaves under Mercury Stress

作　　者：李信茹 苏海磊[1] 周民 米屹东 王凡凡 柳慧芳 沈亚琴[1] 魏源[1] LI Xinru;SU Hailei;ZHOU Min;MI Yidong;WANG Fanfan;LIU Huifang;SHEN Yaqin;WEI Yuan(State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;College of Environment,Hohai University,Nanjing 210098,China)

机构地区：[1]中国环境科学研究院,环境基准与风险评估国家重点实验室,北京100012 [2]河海大学环境学院,江苏南京210098

出　　处：《环境科学研究》2021年第8期1918-1927,共10页Research of Environmental Sciences

基　　金：国家自然科学基金项目(No.41977294);国家自然科学基金青年科学基金项目(No.41907305);科技部科研院所技术开发研究专项(No.2014EG166135)。

摘　　要：为了研究AM(arbuscular mycorrhizal,丛枝菌根)真菌在Hg胁迫下对农作物生长的影响,通过温室盆栽试验,分析不同Hg投加量(0、0.1、1.0和2.0 mg/kg)下,接种AM真菌对水稻植株生物量、株高、叶片叶绿素相对含量、膜质过氧化程度、抗氧化酶系活性、光合速率、气孔导度、胞间CO 2、水分利用效率、可溶性糖和可溶性蛋白含量的影响.结果表明:①在不同Hg投加量下,AM真菌均能促进水稻植株生长.②AM真菌接种能提高水稻叶片叶绿素相对含量,增加水稻叶片光合速率.③接种AM真菌后,水稻叶片MDA(malondialdehyde)含量降低,水稻叶片超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase)和抗坏血酸过氧化物酶(ascorbate peroxidase,APX)活性均升高.综合显著性分析结果来看,当Hg投加量为0.1 mg/kg时,接种AM真菌后水稻整体长势良好,多项生理指标偏高,说明AM真菌在较低Hg投加量下能促进水稻生长,提高水稻对汞的抗性.研究显示,AM真菌能通过促进水稻光合色素分泌来提高水稻光合作用,同时能提高水稻抗氧化酶活性,维持细胞稳态,缓解汞的毒害作用.总之,AM真菌能增强水稻对汞污染的适应能力,促进植株生长发育,降低汞对水稻造成的毒害及损伤,增强抗逆性,且该作用在较低Hg投加量下表现更加明显.Pot experiments were conducted in a greenhouse to study the effects of AM fungi on the growth and photosynthesis under Hg stress,based on the effect of AM fungi on biomass,height,chlorophyll relative content,photosynthetic rate,stomatal conductance,intercellular CO 2,water use efficiency,membrane lipid peroxidation,antioxidant enzyme activities soluble sugar and soluble protein content.The results showed that:(1)Under different Hg pollution conditions,AM fungi could promote the growth of rice plants.(2)The photosynthetic rate and chlorophyll were also increased by AM fungus inoculation,and AM fungi could improve the photosynthesis of rice by promoting the secretion of photosynthetic pigments.(3)AM fungi could decrease the content of MDA and reduce the degree of lipid peroxidation of cell membrane.The activities of superoxide dismutase,catalase,peroxidase,and ascorbate peroxidase were also increased by AM fungus inoculation,which indicated that AM fungi could improve the activity of antioxidant enzymes,maintain cell homeostasis,and alleviate the toxicity of Hg.The results of significance analysis showed that when the concentration of Hg was 0.1 mg kg,the overall growth of rice was better,while a number of physiological indexes were on the high side,indicating that AM fungi could promote the growth of rice and improve the resistance of rice under low mercury concentration.In conclusion,AM fungi can enhance the adaptability of rice to mercury pollution,promote plant growth and development,reduce the toxicity and damage of Hg to rice,and enhance the stress resistance.This effect will be more obvious under the condition of low concentration mercury pollution.

关 键 词：丛枝菌根 水稻 汞 光合作用 抗氧化酶系 

分 类 号：X53[环境科学与工程—环境工程]