摘要
利用开顶式气室(OTC)组成的CO_2浓度自动调控平台,以冬小麦为试验材料,设置CK(对照,环境大气CO_2浓度)、T_1(CO_2浓度比CK增加40μmol/mol)和T_2(CO_2浓度比CK增加200μmol/mol)3个CO_2浓度水平;在每个OTC内设置不施氮(N_0,0 kgN/hm^2)、中氮(N_1,220 kgN/hm^2)和高氮(N_2,400 kgN/hm^2)3个氮肥处理水平,分析冬小麦光合作用、生物量和产量结构变化,探讨CO_2浓度升高和施氮水平对冬小麦光合与生长的影响。结果表明,在较低光强(PAR≤200μmol/(m^2·s))和CO_2浓度(C_i≤300μmol/mol)水平下,各处理的净光合速率(P_n)值均呈直线上升,随后趋于平缓。与CK相比,T_2处理下P_n增加了19.93%(P=0.013),但对最大净光合速率(P_(nmax))、暗呼吸速率(R_(day))、光呼吸速率(R_p)等无显著影响。在拔节—开花期,不同CO_2浓度处理下N_1、N_2与N_0相比显著增加了株高、叶片和茎鞘干重;在抽穗—开花期,T_2N_1与CKN_1相比显著增加了茎鞘干重,增幅为37.4%(P=0.035)。与T_1N_0相比,T_1N_1、T_1N_2显著增加了籽粒数,增幅分别为29.69%(P=0.006)和42.27%(P=0.001);与T_2N_0相比,T_2N_1、T_2N_2显著增加了籽粒数,增幅分别为16.66%(P=0.011)和19.19%(P=0.005)。与T_2N_0相比,T_2N_1、T_2N_2显著增加了千粒重,增幅分别为7.79%(P=0.004)和6.23%(P=0.015)。T_1N_2与CKN_2相比显著增加了小麦经济系数,增幅为3.70%(P=0.025)。研究表明,CO_2浓度升高显著增加了冬小麦光响应曲线的P_n;CO_2浓度升高与施氮处理促进了冬小麦干物质的积累,其中施氮对生长前期物质积累的促进作用相对更大;CO_2浓度升高与施氮处理主要通过增加籽粒数和千粒重共同影响小麦产量结构,其中T_1N_2处理对籽粒数的促进作用最大。
To investigate the effect of elevated CO2 concentration and nitrogen fertilization on photosynthesis and growth of winter wheat,a field experiment was conducted to examine the variations of photosynthesis,biomass and yield structure of winter wheat based on the automatic control system of CO2 concentration with open top chambers(OTCs)using different CO2 concentrations and nitrogen fertilization rates.Three levels of CO2 concentration,i.e.,ambient CO2 concentration(CK),CK+40μmol/mol CO2(T1),and CK+200μmol/mol CO2(T2)and three levels of nitrogen fertilization,i.e.,no nitrogen input(N0,0 kgN/hm^2),medium nitrogen input(N1,220 kgN/hm2),and high nitrogen input(N2,400 kgN/hm2),were applied in this study.The results showed that under the low level of light intensity(PAR≤200μmol/(m^2·s))and CO2 concentration(Ci≤300μmol/mol),the net photosynthetic rate(Pn)increased linearly followed by a leveling off.Compared with CK,Pn was increased by 19.93%under T2 treatment(P=0.013),while no significant differences were found in the maximum net photosynthetic rate(Pnmax),dark respiration rate(Rday),or photorespiration rate(Rp)under CK,T1 and T2 treatments.From the jointing to the flowering stages,the plant height,dry weight of leaf and stem sheath were significantly increased under N1 and N2 treatments compared with N0 with different CO2 concentrations.From the heading to the flowering stages,the dry weight of stem sheath was significantly increased by 37.4%(P=0.035)under T2N1 compared with CKN1.In comparison to T1N0 treatment,the grain number was significantly increased by 29.69%(P=0.006)and 42.27%(P=0.001),respectively,under T1N1 and T1N2 treatments.Compared with T2N0 treatment,the grain number was significantly increased by 16.66%(P=0.011)and 19.19%(P=0.005),respectively,under T2N1 and T2N2 treatments.For the 1000-grain weight,it was significantly increased by7.79%(P=0.004)and 6.23%(P=0.015),respectively,under T2N1 and T2N2 treatments as compared to T2N0 treatment.Compared with CKN2 treatment,the economic coefficient was s
作者
夏晔
胡正华
刘超
刘晓萌
于凌飞
张琳
孙文娟
尤钰杰
XIA Ye;HU Zheng-hua;LIU Chao;LIU Xiao-meng;YU Ling-fei;ZHANG Lin;SUN Wen-juan;YOU Yu-jie(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Jiangsu Key Laboratory of Agricultural Meteorology, Nanjing University of Information Science & Technology, Nanjing, Jiangsu 210044,China;State Key Laboratory of Vegetation and Environmental Change, Institute of Botany,Chinese Academy of Sciences, Beijing 100093, China)
出处
《农业现代化研究》
CSCD
北大核心
2019年第2期333-341,共9页
Research of Agricultural Modernization
基金
国家自然科学基金重点项目(41530533)
国家自然科学基金面上项目(41775152)
江苏省大学生实践创新训练计划项目(201810300070Y)~~
关键词
冬小麦
CO2浓度升高
氮肥
光合作用
产量结构
生物量
winter wheat
elevated CO2 concentration
nitrogen fertilizer
photosynthesis
yield components
biomass