Ethylenediurea(EDU)effects on hybrid larch saplings exposed to ambient or elevated ozone over three growing seasons  

作　　者：Evgenios Agathokleous Mitsutoshi Kitao Takayoshi Koike 

机构地区：[1]Key Laboratory of Agrometeorology of Jiangsu Province,School of Applied Meteorology,Nanjing University of Information Science and Technology(NUIST),Nanjing 210044,People’s Republic of China [2]Research Faculty of Agriculture,Hokkaido University,SapporoHokkaido 060-8589,Japan [3]Hokkaido Research Center,Forestry and Forest Products Research Institute(FFPRI),Sapporo 062-8516,Japan [4]Research Center for Eco-Environmental Science,Chinese Academy of Science,Beijing 100085,People’s Republic of China

出　　处：《Journal of Forestry Research》2022年第1期117-135,共19页林业研究（英文版）

基　　金：partly supported by grant#201802 of the Japan’s Forestry and Forest Products Research Institute(FFPRI);KAKENHI grant#JP17F17102 of the Japan Society for the Promotion of Science(JSPS).E.A.;support from The Startup Foundation for Introducing Talent of Nanjing University of Information Science&Technology(NUIST),Nanjing,China(Grant No.003080)。

摘　　要：Ground-level ozone(O_(3))pollution is a persistent environmental issue that can lead to adverse effects on trees and wood production,thus indicating a need for forestry interventions to mediate O_(3) effects.We treated hybrid larch(Larix gmelinii var.japonica×L.kaempferi)saplings grown in nutrient-poor soils with 0 or 400 mg L^(-1) water solutions of the antiozonant ethylenediurea(EDU0,EDU400)and exposed them to ambient O_(3)(AOZ;08:00-18:00≈30 nmol mol^(-1)) or elevated O_(3)(EOZ;08:00-18:00≈60 nmol mol^(-1))over three growing seasons.We found that EDU400 protected saplings against most effects of EOZ,which included extensive visible foliar injury,premature senescence,decreased photosynthetic pigment contents and altered balance between pigments,suppressed gas exchange and biomass production,and impaired leaf litter decay.While EOZ had limited effects on plant growth(suppressed stem diameter),it decreased the total number of buds per plant,an effect that was not observed in the first growing season.These results indicate that responses to EOZ might have implications to plant competitiveness,in the long term,as a result of decreased potential for vegetative growth.However,when buds were standardized per unit of branches biomass,EOZ significantly increased the number of buds per unit of biomass,suggesting a potentially increased investment to bud development,in an effort to enhance growth potential and competitiveness in the next growing season.EDU400 minimized most of these effects of EOZ,significantly enhancing plant health under O_(3)-induced stress.The effect of EDU was attributed mainly to a biochemical mode of action.Therefore,hybrid larch,which is superior to its parents,can be significantly improved by EDU under long-term elevated O_(3) exposure,providing a perspective for enhancing afforestation practices.

关 键 词：Air pollution Ethylenediurea(EDU) HORMESIS Plant protection Tropospheric ozone(o_3) Larix gmelinii var.japonica×L.kaempferi 

分 类 号：S791.22[农业科学—林木遗传育种]