臭氧浓度升高和增温对水稻叶片光合作用的复合影响  

Combined effects of elevated ozone concentration and warming on photosynthesis of rice leaves

作　　者：周钰清 徐彦森 何龙鑫 张宇杰 冯兆忠 ZHOU Yuqing;XU Yansen;HE Longxin;ZHANG Yujie;FENG Zhaozhong(Jiangsu Provincial Key Laboratory of Agricultural and Ecological Meteorology,School of Ecology and Applied Meteorology,Nanjing University of Information Science&Technology,Nanjing 210044,China)

机构地区：[1]南京信息工程大学生态与应用气象学院,江苏省农业与生态气象重点实验室,南京210044

出　　处：《生态学报》2025年第2期877-888,共12页Acta Ecologica Sinica

基　　金：江苏省碳达峰碳中和专项(BE2022312);国家自然科学基金重点项目(42130714)。

摘　　要：人类活动导致的地表臭氧(O_(3))浓度升高和气候变暖正严重影响作物生长。利用开放式O_(3)浓度与温度升高平台(O_(3)-T-FACE),以南粳9108为实验材料,设置两个O_(3)浓度:环境大气O_(3)浓度(A)和1.5倍环境O_(3)浓度(E),三个增温处理:环境温度(CK)、冠层红外增温1.5℃(+1.5)和2℃(+2)。于灌浆中期和后期测定水稻叶片光合速率和叶绿素含量,以明确O_(3)浓度升高和温度增加对水稻叶片光合作用的复合影响。两年重复实验结果表明,与环境大气O_(3)浓度相比,O_(3)浓度升高对水稻灌浆中期叶片光合指标无显著影响,但显著降低了水稻灌浆后期的饱和光合速率(A_(sat))、气孔导度(g_(s))和叶绿素含量,分别平均下降31.3%、19.9%和30.7%;对胞间CO_(2)浓度(C_(i))、电子传递速率(ETR)、水分利用率(WUE)等指标的影响两年均不显著,说明O_(3)浓度升高导致的A_(sat)降低主要是由于叶绿素含量的下降,而非气孔限制CO_(2)传输。增温显著降低了2022年灌浆后期叶片A_(sat)和g_(s),显著降低2021年灌浆中期和后期叶片C_(i),增加叶片WUE,但对其他光合指标和叶绿素含量无显著影响。灌浆后期叶片光合速率对O_(3)浓度升高和增温的响应存在年际差异,2021年灌浆期间高的环境O_(3)浓度和温度加重了叶片光合损失。实验设置的不同增温幅度间的影响未达到显著性差异,说明开放条件下增加冠层温度1.5—2℃对当前的试验水稻品种不足以产生高温胁迫。O_(3)浓度升高和增温对叶片光合速率和叶绿素含量的复合影响未达显著性水平,意味着高浓度O_(3)和温度对试验水稻品种的叶片光合作用不存在协同或拮抗效应。Rising tropospheric ozone(O_(3))concentration and global warming caused by anthropogenic activities have severely affected crop growth.In this study,japonica rice Nanjing 9108 was used as the test material based on the free-air O_(3)concentration and temperature enhancement(O_(3)-T-FACE)system.The O_(3)concentration were set to ambient O_(3)concentration(A)and 1.5 times ambient O_(3)concentration(E);the warming treatments were set to ambient temperature(CK),canopy temperature+1.5℃(+1.5)and canopy temperature+2℃(+2),respectively.The photosynthetic rate and chlorophyll content of rice leaves were measured at the middle and late grain filling stage to clarify the combined effects of elevated O_(3)concentration and warming on photosynthesis.The results of two years experiments showed that compared with ambient O_(3)concentration,elevated O_(3)concentration had no significant effect on the photosynthetic indexes of rice leaves at the middle grain filling stage,but significantly decreased the saturated photosynthetic rate(Asat),stomatal conductance(g_(s))and chlorophyll content of rice at the late grain filling stage,with an average decrease of 31.3%,19.9%and 30.7%,respectively.The effect on intercellular CO_(2)concentration(C_(i)),electron transfer rate(ETR),water use efficiency(WUE)and other indexes were not significant in the two years,suggesting that elevated O_(3)concentration induced reductions in Asat was mainly due to the decrease in chlorophyll content,rather than the stomatal limitations of CO_(2)transport.Warming significantly reduced the Asat and g_(s)at the late grain filling stage of 2022,significantly reduced the C_(i),and increased the WUE of leaves in the middle and late grain filling stage of 2021,but had no significant effect on other photosynthetic indexes and chlorophyll content.The open experimental conditions of O_(3)-T-FACE platform are greatly affected by the environment.Significant differences in the response of leaf photosynthetic rate to elevated O_(3)concentration and warming across yea

关 键 词：臭氧 增温 光合速率 气孔导度 水分利用率 叶绿素 

分 类 号：S511[农业科学—作物学]