干旱和臭氧浓度升高对元宝枫早生和晚生叶片色素和脱落酸含量的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 干旱和臭氧浓度升高对元宝枫早生和晚生叶片色素和脱落酸含量的影响 DOI: 10.5846/stxb201505060933 作者: 作者单位: 中国科学院生态环境研究中心,中国科学院华南植物园,中国科学院生态环境研究中心,中国农业科学院农业资源与农业区划研究所,中国科学院生态环境研究中心 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31170424，41571053，71533005） The effects of elevated ozone and chronic drought on leaf pigments and abscisic acid contents in early and late-flush leaves of Shantung maple (Acer truncatum Bunge) Author: Affiliation: Research Center for Eco-Environmental Sciences，Chinese Academy of Sciences,South China Botanical Garden, Chinese Academy of Sciences,Central South University,Institute of Agriculture Resources and Regional Planning, Chinese Academy of Agriculture Sciences,Research Center for Eco-Environmental Sciences，Chinese Academy of Sciences Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:臭氧和干旱是威胁我国北方城市植物生长的两大重要因素。于2012年利用开顶式气室，通过设置4个处理（AW-大气环境和水分充足；AW+60-大气增加60 nL/L臭氧+水分充足；AD-大气+干旱处理；AD+60-大气增加60 nL/L臭氧+干旱处理），开展了大气臭氧浓度升高（以下简称“臭氧”）和干旱对元宝枫秋季变色期主要色素含量及脱落酸（ABA）含量的影响研究。结果表明：（1）早生叶在臭氧处理后，总叶绿素和类胡萝卜素分别下降了21%和29.6%、花青苷和类黄酮相对含量显著升高了34.1%和7.3%、脱落酸含量增加了19.8%。干旱处理后，早生叶总叶绿素显著下降了18.7%、花青苷和类黄酮相对含量分别显著升高了37%和7.4%、脱落酸含量显著升高了13%。叶片的上述生理变化将会导致叶片提前变红、叶片早衰和提前脱落。（2）晚生叶在干旱处理后总叶绿素含量减少了18.8%，脱落酸含量增加了33.4%，臭氧以及与干旱共同处理未对晚生叶产生显著影响。（3）臭氧和干旱共同处理后，早生叶总叶绿素含量、花青苷和叶片脱落酸含量存在显著交互作用，交互作用缓解了叶片总叶绿素的下降和花青苷的上升，但未缓解叶片脱落酸含量的增加。综上，早生叶和晚生叶对臭氧和干旱处理的响应不同，早生叶对臭氧处理响应大于晚生叶，而晚生叶对干旱更敏感。臭氧和干旱处理均加速了叶片衰老，二者共同处理后叶片脱落风险增加。 Abstract:The changing color of leaves in autumn is not only necessary for the growth of foliage trees but is also important for urban landscape interests. Red color in maple leaves relates to the synthesis of anthocyanin and the degraded pigments. Ozone (O3) is an important phytotoxic pollutant, which may affect the basic physiological functions of plants due to its highly reactive oxidative characteristics. The increased consumption of fossil fuels in China has led to increased emission of O3 precursors and visible plant injury induced by high O3 concentration frequently occurs around Beijing. In addition, trees are often subjected to periodic drought in North China with the frequency and the severity of drought events projected in the background of climate change. Drought in summer usually coincides with episodes of high O3 concentrations, which, together, may affect plant growth including color expression and leaf senescence of foliage tree species in fall. Although numerous publications have reported the effects of elevated O3 concentration or drought stress on trees, little is known about the possible interactions between anthocyanin and flavonoid in Asian maple species. To investigate the effects of chronic drought stress and elevated O3 concentrations on leaf pigments and abscission of Shantung maple (Acer truncatum Bunge), we set up 12 open-top chambers with four treatments (AW: non-filtered ambient air and well watered; AW+60: non-filtered ambient air plus 60 nL/L O3 and well watered; AD: non-filtered ambient air and drought; AD+60: non-filtered ambient air plus 60 nL/L O3 and drought) in a suburb of Beijing, China. Total chlorophyll (total Chl), carotenoid (Car), anthocyanin, flavonoid, and abscisic acid (ABA) contents in early and late-flush leaves were measured in October of the first year. Leaves that unfolded from July 1 to 7 were marked as early-flush leaves and the AOT40 (The cumulative O3 exposure, which was described as the accumulated hourly mean O3 concentrations over 40 ppb during O3 fumigation period) was 28.2 μL L-1 h when harvested. Late-flush leaves unfolded from September 1 to 7 and the AOT40 was 14.2 μL L-1 h when harvested. The results showed: (1) For early-flush leaves, elevated O3 significantly decreased the total Chl and Car contents by 21% and 29.6%, respectively, increased anthocyanin and flavonoid relative contents by 34.1% and 7.3%, respectively, and increased ABA contents by 19.8%. Drought stress decreased the total Chl by 18.7%, increased the relative contents of anthocyanin and flavonoid by 37% and 7.4%, respectively, and increased ABA contents by 13%. These physiology changes would collectively lead to leaf reddening, senescence, and abscission in advance of autumn. (2) Late-flush leaves only responded to drought treatments as indicated by a significant decrease of 18.8% in total Chl and an increase of 33.4% in ABA contents. (3) Significant interactions were found in total Chl, anthocyanin, and ABA contents of early-flush leaves, as indicated by the fact that the decrease in total Chl and increase in anthocyanin were mitigated, but the increase in ABA contents was aggravated. In conclusion, early and late-flush leaves responded differently to elevated O3 and drought stress. Early-flush leaves responded more to ozone treatment, while late-flush leaves were more sensitive to drought stress. Both treatments lead to leaf early senescence and their interactive treatments may increase the risk of early abscission. This study may provide a better understanding of autumnal leaf growth and the phenology response to elevated O3 and drought stress in the coming future. 参考文献 相似文献 引证文献