摘要
为阐明大气CO2浓度升高和氮肥交互作用对C4作物玉米光合生理和产量的影响,本研究利用自由大气CO2富集(FACE)平台,以玉米品种‘郑单958’为试验材料,在不同施氮量[常氮180 kg(N)·hm^-2、低氮72 kg(N)·hm^-2]下比较大气CO2浓度[(400±15)μmol·mol^-1]和高CO2浓度[(550±15)μmol·mol^-1]对玉米生长的影响。结果表明:1)大气CO2浓度升高使玉米苗期叶片叶绿素浓度显著(P=0.025)增加9.5%,抽雄期净光合速率显著(P=0.009)增加9.0%;低氮和常氮下,高CO2浓度使玉米各主要生育期胞间CO2浓度分别显著增加34.8%~48.5%和40.0%~49.4%,气孔导度在大口期和抽雄期分别显著下降21.6%(P=0.015)和22.1%(P=0.010),玉米叶片水分利用效率在大口期、抽雄期和灌浆期分别显著增加12.9%(P=0.002)、9.8%(P=0.019)和18.8%(P=0.001);高CO2浓度使玉米非光化学淬灭呈降低趋势、PSII有效光化学量子产量有增加趋势;相同氮水平下,高CO2浓度对玉米产量没有显著影响。2)高CO2浓度和合理施氮交互作用对玉米功能叶叶绿素含量、净光合速率、PSⅡ有效光化学量子产量增加有一定的促进作用,如在大口期和抽雄期,常氮+高CO2浓度处理叶绿素含量比低氮+大气CO2浓度处理增加17.3%和10.7%,高CO2浓度和合理施氮量交互作用有增加玉米产量的潜力,合理增加施氮量促进了CO2肥效的发挥。在未来大气CO2浓度升高条件下合理施氮对C4作物玉米生长发育有促进作用。
Since the industrial revolution,the concentration of atmospheric CO2 has increased from 280μmol×mol^-1 to 400μmol×mol^-1.Nitrogen is a necessary element for many important enzyme-mediated processes in plant growth and is the primary nutrient needed for plant growth.Among different C4 crops grown worldwide,including China,maize is the most widely planted crop.Clear answers regarding the effect of elevated atmospheric CO2 concentration(eCO2)on corn growth and the interaction between eCO2 and nitrogen fertilizers(N)are yet not to be attained.Studying the impact of eCO2 on maize growth under different nitrogen supply conditions is important to assess the role of climate change in the C4 crop growth.A Free Air CO2 Enrichment(FACE)facility was used in this experiment.The FACE facility has six octagon loops for eCO2,(550±15)μmol×mol^-1,and six additional octagon loops for ambient CO2 concentration of(400±15)μmol×mol^-1(aCO2);three of which are eCO2 experimental loops and the other three are aCO2 experimental loops applied with conventional nitrogen fertilizer,180 kg(N)·hm^-2(CN).The rest are low nitrogen,72 kg(N)·hm^-2(LN),application treatments.Twelve experimental loops were arranged randomly in the maize field,with the plants spacing of 25 cm and a rows spacing of 60 cm.Results showed that under eCO2,the chlorophyll concentration of maize seedling leaves increased significantly by 9.5%,and the net photosynthetic rate increased by 9.0%at the tasseling stage.During the maize growth period,eCO2 significantly enhanced the intercellular CO2 concentration by 34.8%-48.5%and 40.0%-49.4%under low nitrogen and conventional nitrogen application conditions,respectively.In addition,the stomatal conductance decreased by 21.6%and 22.1%at the 12-leaf and the tasseling stages,respectively.As a consequence of decreased stomatal conductance,the efficiency of water consumption in maize leaves increased by 12.9%,9.8%,and 18.8%at the 12-leaf stage,tasseling stage and filling stage,respectively.eCO2 also decreased Non-Photochemi
作者
牛晓光
杨荣全
李明
段碧华
刁田田
马芬
郭李萍
NIU Xiaoguang;YANG Rongquan;LI Ming;DUAN Bihua;DIAO Tiantian;MA Fen;GUO Liping(Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Beijing 100081,China;College of Bioscience and Resource Environment,Beijing University of Agriculture,Beijing 102206,China)
出处
《中国生态农业学报（中英文）》
CAS
CSCD
北大核心
2020年第2期255-264,共10页
Chinese Journal of Eco-Agriculture
基金
“十三五”国家重点研发计划专项课题(2017YFD0300301)资助~~
关键词
大气CO2浓度升高
玉米
施氮量
光合作用
叶绿素荧光
产量
Elevated atmospheric CO2 concentration
Maize
Nitrogen fertilizer application
Photosynthesis
Chlorophyll fluorescence
Yield
