大气CO2浓度和氮肥水平对小麦籽粒产量和品质的影响

应用FACE平台,研究了不同氮肥水平下大气CO₂浓度升高对小麦籽粒产量和品质的影响.结果表明： 大气CO₂浓度升高（FACE）和增施氮肥显著提高了小麦籽粒产量、穗数、穗粒数和生物量.但FACE处理对收获指数无显著影响.FACE处理显著降低了籽粒蛋白质、醇溶蛋白、谷蛋白、面筋含量和沉降值,显著提高了小麦籽粒淀粉及其组分含量,而氮肥处理具有相反的效应.面团稳定时间及峰值黏度、最终黏度、反弹值等黏度特征参数在FACE和高氮水平下显著增加.此外,CO₂浓度与氮肥水平互作对小麦籽粒产量和生物量有显著的正效应,但对籽粒品质无显著影响.在未来大气CO₂浓度升高的情况下,维持较高的施氮量有利于提高小麦籽粒产量,改善淀粉糊化特性,缓解小麦品质特性的下降.     

大气CO2浓度和氮肥水平对小麦籽粒产量和品质的影响

应用FACE平台,研究了不同氮肥水平下大气CO₂浓度升高对小麦籽粒产量和品质的影响.结果表明： 大气CO₂浓度升高（FACE）和增施氮肥显著提高了小麦籽粒产量、穗数、穗粒数和生物量.但FACE处理对收获指数无显著影响.FACE处理显著降低了籽粒蛋白质、醇溶蛋白、谷蛋白、面筋含量和沉降值,显著提高了小麦籽粒淀粉及其组分含量,而氮肥处理具有相反的效应.面团稳定时间及峰值黏度、最终黏度、反弹值等黏度特征参数在FACE和高氮水平下显著增加.此外,CO₂浓度与氮肥水平互作对小麦籽粒产量和生物量有显著的正效应,但对籽粒品质无显著影响.在未来大气CO₂浓度升高的情况下,维持较高的施氮量有利于提高小麦籽粒产量,改善淀粉糊化特性,缓解小麦品质特性的下降.     

大气CO2浓度升高对稻季土壤中麦秸降解及氮素分趋的影响

利用中国唯一的稻麦轮作FACE(free-air carbon dioxide enrichment,开放式空气CO2浓度增高)试验平台,研究大气CO2浓度升高对稻季土壤中小麦秸秆降解速率及其氮素分趋的影响.试验设置Ambient(目前空气对照)和FACE(Ambient+200 μmol·mol-1)两个CO2浓度以及低氮处理(LN,150 kg·hm-2)和高氮处理(HN,250 kg·hm-2)两个氮肥水平,在稻季之初按标记麦秸/土壤重量比0.3%添加15N标记小麦秸秆,根据水稻生长时期依次采样测定秸秆降解速率,并通过分析土壤全氮、植株全氮及其15N丰度来观察已降解秸秆的氮素分趋情况.结果发现,大气CO2浓度升高对高氮处理土壤中小麦秸秆降解速率没有显著影响,但显著促进了低氮处理土壤中小麦秸秆的降解(p < 0.05),使其提高到与高氮处理土壤相当水平;大气CO2浓度升高显著增加了已降解秸秆中氮素的流失,在高氮处理土壤中尤为严重,而对植物吸收已降解秸秆中的氮素没有显著影响.结果表明,大气CO2浓度升高在土壤氮素相对不足时会加速土壤中小麦秸秆的降解,而在土壤氮素相对充足时又会加大降解秸秆中氮素的流失.     

氮、硫肥与灌浆后期高温胁迫对小麦籽粒产量和品质的影响

灌浆期高温胁迫通常导致小麦籽粒产量降低、品质变差.为了探索有效缓解高温胁迫不利影响的有效措施,在大田条件下,以济麦20为试验材料,运用后期高温棚增温的方法,研究了氮、硫肥与灌浆后期高温对小麦籽粒产量和品质的影响.结果表明:高温处理后小麦千粒质量、籽粒产量显著降低(19.7%～28.3%),蛋白质含量升高,蛋白质组分中不溶性谷蛋白含量下降,可溶性谷蛋白含量上升,面团形成时间和稳定时间缩短;氮肥追施比例由50%增加到70%,非高温处理的籽粒产量无显著变化,不溶性谷蛋白质含量和谷蛋白聚合指数(不溶性谷蛋白含量/可溶性谷蛋白含量)升高,面团形成时间和稳定时间延长;高温处理的千粒质量和籽粒产量因氮肥追施比例提高而提高(2.07%～3.58%),面团形成时间和稳定时间缩短;不论高温处理还是非高温处理,与追施硫肥相比,硫肥基施提高籽粒产量、谷蛋白聚合指数,延长面团形成时间和稳定时间;为了有效缓解灌浆后期高温对小麦籽粒产量和品质的不利影响,硫肥基施、氮肥施用基追比50%:50%是较为适宜的施肥模式.     

CO2浓度升高和施氮条件下小麦根际呼吸对土壤呼吸的贡献

依托FACE技术平台,采用稳定13C同位素技术,通过将小麦(C3作物)种植于长期单作玉米(C4作物)的土壤上,研究了大气CO2浓度升高和不同氮肥水平对土壤排放CO2的δ13C值及根际呼吸的影响.结果表明:种植小麦后土壤排放CO2的δ13C值随作物生长逐渐降低,CO2浓度升高200 μmol·mol-1显著降低了孕穗、抽穗期(施氮量为250 kg·hm-2,HN)与拔节、孕穗期(施氮量为150 kg·hm-2,LN)土壤排放CO2的δ13C值,显著提高了孕穗、抽穗期的根际呼吸比例.拔节至成熟期,根际呼吸占土壤呼吸的比例在高CO2浓度下为24％～48％ (HN)和21％ ～48％ (LN),在正常CO2浓度下为20％ ～36％ (HN)和19％～32％(LN).不同CO2浓度下土壤排放CO2的δ13C值和根际呼吸对氮肥增加的响应不同,CO2浓度与氮肥用量在拔节期对根际呼吸的交互效应显著.     

CO2浓度升高与氮添加对三江平原湿地小叶章生长的影响

利用开顶箱薰气室,设置正常大气CO₂浓度(350 μmol·mol^-1)、高CO₂浓度(700 μmol·mol^-1)2个CO₂水平和不施氮(0 g N·m^-2)、中氮(5 g N·m^-2)和高氮(15 g N·m^-2)3个氮素水平,研究CO₂浓度升高和氮肥施用对三江平原草甸小叶章生长的影响.结果表明：随着CO₂浓度升高,小叶章物候期提前,其中抽穗期提前1～2 d,成熟期提前3 d;不施氮、中氮和高氮水平下, CO₂浓度升高使小叶章的分蘖分别增加8.2%(P<0.05)、8.4%(P<0.05)和5.5%(P>0.05);在小叶章生长初期,CO₂浓度升高对其生物量的增加有促进作用,拔节期和抽穗期小叶章地上生物量分别增加12.4%和20.9%(P<0.05);生长后期则对小叶章地下生物量的促进作用增大,腊熟期和成熟期的地下生物量分别增加20.5%和20.9% (P<0.05).小叶章生物量对高浓度CO₂的响应与供氮水平有关,供氮充足条件下, 高浓度CO₂对生物量的促进效应更大.     

Elevated CO2, rhizosphere processes,and soil organic matter decomposition

The rhizosphere is one of the key fine-scale components of C cycles. This study was undertaken to improve understanding of the potential effects of atmospheric CO2 increase on rhizosphere processes. Using C isotope techniques, we found that elevated atmospheric CO2 significantly increased wheat plant growth, dry mass accumulation, rhizosphere respiration, and soluble C concentrations in the rhizosphere. When plants were grown under elevated CO2 concentration, soluble C concentration in the rhizosphere increased by approximately 60%. The degree of elevated CO2 enhancement on rhizosphere respiration was much higher than on root biomass. Averaged between the two nitrogen treatments and compared with the ambient CO2 treatment, wheat rhizosphere respiration rate increased 60% and root biomass only increased 26% under the elevated CO2 treatment. These results indicated that elevated atmospheric CO2 in a wheat-soil system significantly increased substrate input to the rhizosphere due to both increased root growth and increased root activities per unit of roots. Nitrogen treatments changed the effect of elevated CO2 on soil organic matter decomposition. Elevated CO2 increased soil organic matter decomposition (22%) in the nitrogen-added treatment but decreased soil organic matter decomposition (18%) without nitrogen addition. Soil nitrogen status was therefore found to be important in determining the directions of the effect of elevated CO2 on soil organic matter decomposition.     

水稻生长及其体内C、N、P组成对开放式空气CO2浓度增高和N、P施肥的响应

采用FACE（Free Air Carbon-dioxide Enrichment)技术,研究了不同N、P施肥水平下,水稻分蘖期、拔节期、抽穗期和成熟期根、茎、穗生长,C/N比、N、P含量及N、P吸收对大气CO2浓度升高的响应,结果表明,高CO2促进水稻茎、穗和根的生长,增加分蘖期叶干重,对拔节期、抽穗期的成熟期叶干重没有显著增加,降低茎、叶N含量;增加抽穗期穗N含量;降低成熟期穗N含量;对分蘖期根N含量影响不显著,而降低拔节期,抽穗期和成熟期根N含量,增加拔节期、抽穗期和成熟期叶P含量,对茎、穗、根P含量影响不显著,水稻各组织C含量变化不显著,C/N比增加,显著增加水稻地上部分P吸收;增加N吸收,但没有统计显著性,N、P施用对水稻各组织生物量没有显著影响,高N（HN）比低N（LN）增加组织中N含量,而不同P肥水平间未表现出明显差异,高N条件下高CO2增加水稻成熟期地下部分/地上部分比,文中还讨论了高CO2对N、P含量及地下部分/地上部分比的影响机制。     

Effect of long-term application of manure and fertilizer on biological and biochemical activities in soil during crop development stages

A field experiment was conducted to investigate the effect of six long-term (34-year) fertilizer and farmyard manure (FYM) treatments (Control, N, NP, NPK, NPK+S, NPK+FYM) and three physiological stages of wheat growth on the microbial biomass carbon (MBC), nitrogen (MBN) and dehydrogenase, mineralizable N and phosphatase activities in soil. It was found that a balanced application of NPK+FYM gave the highest values for the measured parameters and lowest at the control. Values were generally highest at tillering, followed by the flowering and dough stages. A significant positive interaction between fertilizer treatments and physiological stages of wheat growth was observed, being highest at maximum tillering due to application of NPK+FYM. Stepwise regressions have revealed that grain yield of wheat was significantly associated with mineralizable N at tillering (R(2)=0.80), MBC at flowering (R(2)=0.90) and alkaline phosphatase activity (R(2)=0.70) at dough stages of wheat growth.     

施氮和大气CO2浓度升高对小麦旗叶光合电子传递和分配的影响

采用开顶式气室盆栽培养小麦,设计2个大气CO2浓度(正常:400 μmol.mol-1;高:760 μmol·mol-1)、2个氮素水平(0和200 mg·kg-1土)的组合处理,通过测定小麦抽穗期旗叶氮素和叶绿素浓度、光合速率(Pn)-胞间CO2浓度(C1)响应曲线及荧光动力学参数,来测算小麦叶片光合电子传递速率等,研究了高大气CO2浓度下施氮对小麦旗叶光合能量分配的影响.结果表明:与正常大气CO2浓度相比,高大气CO2浓度下小麦叶片氮浓度和叶绿素浓度降低,高氮处理的小麦叶片叶绿素a/b升高.施氮后小麦叶片PSⅡ最大光化学效率(Fv/Fm)、PSⅡ反应中心最大量子产额(Fv'/Fm')、PSⅡ反应中心的开放比例(qr)和PSⅡ反应中心实际光化学效率(φPSⅡ)在大气CO2浓度升高后无明显变化,虽然叶片非光化学猝灭系数(NPQ)显著降低,但PSⅡ总电子传递速率(JF)无明显增加;不施氮处理的Fv'/Fm'、φPSⅡ和NPQ在高大气CO2浓度下显著降低,尽管Fv/Fm和qp无明显变化,JF仍显著下降.施氮后小麦叶片JF增加,参与光化学反应的非环式电子流传递速率(Jc)明显升高.大气CO2浓度升高使参与光呼吸的非环式电子流传递速率(J0)、Rubisco氧化速率(V0)、光合电子的光呼吸/光化学传递速率比(J0/Jc)和Rubisco氧化/羧化比(V0/Vc)降低,但使Jc和Rubisco羧化速率(Vc)增加.因此,高大气CO2浓度下小麦叶片氮浓度和叶绿素浓度降低,而增施氮素使通过PSⅡ反应中心的电子流速率显著增加,促进了光合电子流向光化学方向的传递,使更多的电子进入Rubisco羧化过程,Pn显著升高.     

CO2浓度增加和不同氮肥水平对冬小麦根系呼吸及生物量的影响

 依托FACE(Free-air CO₂ enrichment)研究平台, 利用特制分根集气生长箱, 采用静态箱-GC(Gas chromatography)法, 连续两年研究 了大气CO₂浓度升高和不同氮肥水平对冬小麦拔节期、孕穗抽穗期和灌浆末期的根系呼吸及生物量的影响。两季结果表明, CO₂浓度升高和高氮 肥量均不同程度地增加了3个阶段的地上部和地下部的生物量, 这有利于增加根茬的还田量; CO₂浓度升高对冬小麦不同生长阶段的根系呼吸影 响不同, 在拔节期影响较小;孕穗抽穗期显著增加了根系呼吸, 2004~2005季分别增加33.8%(148.1 mg N&;#8226;kg^-1 干土, HN)和43.9%(88.9 mg N&;#8226;kg^-1 干土, LN), 2005~2006季分别为23.8%(HN)和28.9%(LN); 而灌浆末期显著降低了根系呼吸, 2004~2005季分别降低31.4%(HN)和23.3% (LN), 2005~2006季分别为25.1%(HN)和18.5%(LN); 高施氮量比低施氮量促进了根系呼吸; 随着作物生长根系呼吸与地下生物量呈显著线性负相 关, 高CO₂环境中的R²变小,表明随着作物生长发育高CO₂浓度降低了作物根系呼吸与地下部生物量积累间的相关性.     

二氧化碳浓度增高对稻、麦品质影响研究进展

作物品质的形成是品种遗传特性和环境条件综合作用的结果.一般认为大气中CO₂浓度增高将对作物品质产生重要影响.本文分别从蛋白质与氮含量、微量元素以及其他品质性状等3个方面综述了国内外关于CO₂浓度增高对水稻、小麦品质影响的研究进展,强调了该领域研究的必要性和紧迫性,并提出了研究的重点内容及主要方向.主要包括：大气中CO₂浓度增高对水稻、小麦品质的直接影响及品种间的差异;大气中CO₂浓度增高及其与其它气候因子协同作用对水稻、小麦品质的综合影响及其指标量化;大气中CO₂浓度增高及气候变化对水稻、小麦品质形成过程的影响机理;适应CO₂浓度增高的水稻、小麦品质改良育种的方向与策略;适应CO₂浓度增高的水稻、小麦品质改良的综合生产技术体系和分子标记及转基因技术在水稻、小麦品质改良育种方面的应用.     

不同水分状况下追施氮肥对冬小麦产量及其构成因素的影响

通过盆栽试验研究了不同水分状况下追施氮肥对冬小麦产量及其构成因素的影响,结果表明,干旱胁迫条件下,氮肥早施比晚施好,低量氮肥比高量氮好,而且不同施氮处理对有效穗数和每穗粒数的影响差异达显著水平,但对千粒重无明显影响;水肥配合条件下,氮素的作用得到充分发挥,产量得到大幅度提高,而且对有效穗数,每穗粒数和千粒重都产生显著的影响,拔节期是冬小麦对水肥效应的关键期和亏缺敏感期,这个时期供水供肥可以显著提高产量,同时增加了穗粒数和千粒重。     

大气CO2浓度和温度升高对作物生理生态的影响

论述了大气CO2浓度和温度升高下的植物生长,光合作用,产量以及水分养分利用效率等方面的研究进展,未来高CO2浓度下,光合作用速率有不同程度的提高,生物量和产量增加;气孔导度降低,水分利用效率（WUE）提高,一般地上部分和根系尤其是细根生物量增加,凋落物量随之增加,C/N比率提高,植物残体的腐解速率降低,CO2浓度升高后,会给根际微生物带来更多的底物,从而提高了微生物活性,加速养分的矿化过程,改善植物的养分状况。     

氮肥后移对抽穗后水分胁迫下冬小麦光合特性及产量的影响

采用子母桶栽土培法模拟冬小麦抽穗后不同的水分胁迫状态,研究了氮肥后移对冬小麦光合特性及产量的影响.设置3个氮肥处理,分别为N₁(基肥∶拔节肥∶开花肥=10∶0∶0)、N₂(6∶4∶0)和N₃(4∶3∶3),模拟冬小麦抽穗后2种水分胁迫(渍水胁迫、干旱胁迫),设正常供水为对照.结果表明：相同供水条件下,N₂和N₃处理较N₁处理显著提高冬小麦灌浆期旗叶的SPAD和光合速率,确保了收获时较高的穗数、穗粒数和地上部分生物量;氮肥后移处理显著提高了冬小麦的耗水量,但其籽粒产量和水分利用效率也显著提高.相同氮肥条件下,干旱胁迫和渍水胁迫处理较正常供水显著降低了冬小麦开花期和灌浆期旗叶的光合速率、千粒重、穗粒数和产量.与正常供水相比,各氮肥条件下干旱胁迫和渍水胁迫处理花后旗叶光合速率及籽粒产量的减小幅度均表现为N₁＞N₂＞N₃.表明氮肥后移通过提高旗叶SPAD、减缓花后旗叶光合速率的下降幅度、增加地上部分干物质积累量,调控产量及其构成要素,以减轻逆境灾害(干旱和渍水胁迫)对产量的影响.     

Effects of elevated CO2 and N addition on growth and N2 fixation of a legume subshrub (Caragana microphylla Lam.) in temperate grassland in China

It is well demonstrated that the responses of plants to elevated atmospheric CO(2) concentration are species-specific and dependent on environmental conditions. We investigated the responses of a subshrub legume species, Caragana microphylla Lam., to elevated CO(2) and nitrogen (N) addition using open-top chambers in a semiarid temperate grassland in northern China for three years. Measured variables include leaf photosynthetic rate, shoot biomass, root biomass, symbiotic nitrogenase activity, and leaf N content. Symbiotic nitrogenase activity was determined by the C(2)H(2) reduction method. Elevated CO(2) enhanced photosynthesis and shoot biomass by 83% and 25%, respectively, and the enhancement of shoot biomass was significant only at a high N concentration. In addition, the photosynthetic capacity of C. microphylla did not show down-regulation under elevated CO(2). Elevated CO(2) had no significant effect on root biomass, symbiotic nitrogenase activity and leaf N content. Under elevated CO(2), N addition stimulated photosynthesis and shoot biomass. By contrast, N addition strongly inhibited symbiotic nitrogenase activity and slightly increased leaf N content of C. microphylla under both CO(2) levels, and had no significant effect on root biomass. The effect of elevated CO(2) and N addition on C. microphylla did not show interannual variation, except for the effect of N addition on leaf N content. These results indicate that shoot growth of C. microphylla is more sensitive to elevated CO(2) than is root growth. The stimulation of shoot growth of C. microphylla under elevated CO(2) or N addition is not associated with changes in N(2)-fixation. Additionally, elevated CO(2) and N addition interacted to affect shoot growth of C. microphylla with a stimulatory effect occurring only under combination of these two factors.     

强筋与弱筋小麦籽粒蛋白质组分与加工品质对灌浆期弱光的响应

选用强筋小麦品种济麦20和弱筋小麦品种山农1391,在大田试验条件下,分别于籽粒灌浆前期(花后6—9 d)、中期(花后16—19 d)和后期(花后26—29 d)对小麦进行弱光照处理,研究了籽粒产量、蛋白质组分及加工品质的变化。灌浆期弱光显著降低小麦籽粒产量,灌浆中期对济麦20和灌浆后期对山农1391的产量降幅最大。弱光处理后,籽粒氮素积累量及氮素收获指数减少。但弱光使籽粒蛋白质含量显著升高,其中灌浆中期弱光升幅最大,原因可能是由于其粒重降低造成的。弱光对可溶性谷蛋白无显著影响,但增加不溶性谷蛋白含量,使谷蛋白聚合指数显著升高,面团形成时间和稳定时间亦升高,籽粒灌浆中、后期弱光对上述指标的影响较前期大。灌浆期短暂的弱光照对改善强筋小麦粉质仪参数有利,但使弱筋小麦变劣;并均伴随籽粒产量的显著降低这一不利影响。     

Response of wheat restricted‐tillering and vigorous growth traits to variables of climate change

The response of wheat to the variables of climate change includes elevated CO₂, high temperature, and drought which vary according to the levels of each variable and genotype. Independently, elevated CO₂, high temperature, and terminal drought affect wheat biomass and grain yield, but the interactive effects of these three variables are not well known. The aim of this study was to determine the effects of elevated CO₂ when combined with high temperature and terminal drought on the high‐yielding traits of restricted‐tillering and vigorous growth. It was hypothesized that elevated CO₂ alone, rather than combined with high temperature, ameliorates the effects of terminal drought on wheat biomass and grain yield. It was also hypothesized that wheat genotypes with more sink capacity (e.g. high‐tillering capacity and leaf area) have more grain yield under combined elevated CO₂, high temperature, and terminal drought. Two pairs of sister lines with contrasting tillering and vigorous growth were grown in poly‐tunnels in a four‐factor completely randomized split‐plot design with elevated CO₂ (700 µL L^?1), high day time temperature (3 °C above ambient), and drought (induced from anthesis) in all combinations to test whether elevated CO₂ ameliorates the effects of high temperature and terminal drought on biomass accumulation and grain yield. For biomass and grain yield, only main effects for climate change variables were significant. Elevated CO₂ significantly increased grain yield by 24–35% in all four lines and terminal drought significantly reduced grain yield by 16–17% in all four lines, while high temperature (3 °C above the ambient) had no significant effect. A trade‐off between yield components limited grain yield in lines with greater sink capacity (free‐tillering lines). This response suggests that any positive response to predicted changes in climate will not overcome the limitations imposed by the trade‐off in yield components.     

Effects of elevated CO2 concentration, supplemental irrigation and nitrogenous fertilizer application on rain-fed spring wheat yield

It is expected that the CO₂ concentration of the Earth’s atmosphere will reach 600–1000 ppm by the end of the 21st century. Therefore, in this study, we evaluated the effects of elevated CO₂ concentrations on the development of rain-fed spring wheat in an attempt to identify a practical pathway to increase crop production. To accomplish this, a field experiment was conducted at Guyuan Experimental Station in a semiarid region of China during 2005–2007. During this experiment, the CO₂ concentration was increased to 40.0 ppm and supplemental irrigation and nitrogenous fertilizer (N fertilizer) were applied. The experimental results showed that the elevated CO₂ concentration significantly improved the thousand-grain weight and the grain number per spike. Furthermore, supplemental irrigation and N fertilizer application during the elongation and booting stage of rain-fed spring wheat in conjunction with an elevated CO₂ concentration improved the water use efficiency (WUE), nitrogen use efficiency (NUE), thousand-grain weight, and the yield by 14.6%, 39.6%, 9.3%, and 14.7%, respectively, when compared to groups subjected to the same treatment but not grown under elevated CO₂ concentrations. Furthermore, the spring wheat yield was improved by 81.8% in response to an elevated CO₂ concentration, 60 mm of supplemental irrigation and applied N fertilizer (37.5 g m^?2 NH₄NO₃). However, the presence of an elevated CO₂ concentration without supplemental irrigation and N fertilizer only resulted in an increase in the wheat yield of 7.8%. Consequently, the combination of elevated CO₂ concentration, supplemental irrigation and N fertilizer application played an important role in the improvement of WUE, NUE, thousand-grain weight, and grain yield of rain-fed spring wheat in this region.     

二氧化碳和臭氧浓度升高对春小麦生长及次生代谢的影响

通过开顶式气室(OTCs)研究了OTC对照（自然CO₂浓度约342 μmol·mol^-1,O₃浓度约30 nmol·mol^-1）、高浓度CO₂（550 μmol·mol^-1）、高浓度O₃（浓度为80 nmol·mol^-1）及其交互作用（CO₂ 550 μmol ·mol^-1,O₃ 80 nmol·mol^-1）对春小麦不同发育时期生物量、总酚量、黄酮含量及成熟期产量性状的影响.结果表明：CO₂浓度增加条件下,春小麦生物量和产量性状都显著高于OTC对照（P<0.05）;而O₃浓度升高条件下,小麦生物量降低,株高、穗长、穗粒质量及千粒重也显著低于对照;CO₂和O₃交互作用下各项指标处于二者之间.说明CO₂可以缓解O₃对小麦的负效应,而O₃对CO₂的正效应具有削弱作用,但二者的作用并非简单的叠加.CO₂、O₃浓度增加及其交互作用显著增加了春小麦叶片中的总酚含量,其中两者交互作用的效应更大,但在小麦生长后期,总酚含量增加量比对照有所降低.在小麦生长前期,各处理总黄酮含量均低于对照;而在成熟期,各处理都显著高于对照.