文献类型：期刊文献

中文题名：O3胁迫对三种楠木幼苗光合作用的影响及伤害症状

英文题名：Effects of Elevated O_3 Level on Photosynthesis and Injury of Phoebe and Machilus Seedlings in Subtropical China

作者：于浩[1] 尚鹤[1] 陈展[1] 曹吉鑫[1]

第一作者：于浩

机构：[1]中国林业科学研究院森林生态环境与保护研究所,国家林业局森林生态环境重点实验室,北京100091

年份：2016

卷号：29

期号：6

起止页码：902-910

中文期刊名：林业科学研究

外文期刊名：Forest Research

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；

基金：国家林业公益性行业专项“森林对O3和大气N沉降胁迫的响应”(201304313);国家自然科学基金“亚热带典型针叶和阔叶树种细根动态和周转对大气臭氧胁迫的响应研究”(31370606)

语种：中文

中文关键词：O3;光合作用;Pn-PAR响应参数;非气孔限制因素;伤害症状

外文关键词：O3; photosynthesis; Pn-PAR response parameters; non-stomatal factors; injury symptoms

分类号：S792.24

摘要：[目的]随着全球O_3浓度升高,O_3胁迫对植物影响的研究已成为研究的热点之一。我国的相关研究较少,主要以农作物为主,且大多局限在北方地区。本研究探讨O_3胁迫下,亚热带三种楠木幼苗光合作用的变化规律及其可见伤害症状,以期为后续研究提供理论依据。[方法]以一年生亚热带乡土树种桢楠、闽楠和刨花楠幼苗为材料,采用开顶式气室(OTCs),研究低浓度O_3、环境大气、100 n L·L-1O_3、150 n L·L-1O_3处理对光合作用的影响及伤害症状。[结果]研究表明:(1)O_3胁迫下,三种楠木幼苗的光合作用受到一定的抑制,气孔导度和净光合速率的相关性降低,对光合有效辐射的利用范围整体减小,出现了明显的光抑制现象。O_3浓度越高,对桢楠和刨花楠光合作用的抑制效果越明显,而100 n L·L-1O_3处理对闽楠光合作用的抑制效果较150 n L·L-1O_3处理明显。环境大气中的O_3浓度均值较低,但由于其较高的O_3浓度峰值,仍对三种楠木幼苗的光合作用产生了一定的抑制。与环境大气相比,低浓度O_3处理通过消除较高的O_3浓度峰值从而缓解了O_3对光合作用的不利影响。(2)O_3胁迫下,桢楠叶片出现褪绿、黄斑和坏死斑的症状,闽楠叶片出现褪绿、黄斑和水渍的症状,刨花楠叶片出现红褐色斑、水渍、坏死斑、卷曲皱缩、失水萎蔫的症状。三种楠木幼苗叶片的伤害症状随O_3浓度的增加而更明显。[结论]三种楠木幼苗叶片的光合作用均受到O_3的抑制,并出现了伤害症状,可作为O_3污染的指示树种。光合作用对O_3敏感性的关系为:刨花楠>闽楠>桢楠,其中刨花楠对O_3更敏感,伤害症状也较多样,因此指示O_3污染的效果更好。
[Objective]To study the effects of O_3 on the change law of photosynthesis and occurrence of visible symptoms. [Methods]One-year-old seedlings of Phoebe zhennan S. Lee et FNWei,Phoebe bournei（ Hemsl.） Yang and Machilus pauhoi Kanehira,the native tree species in subtropical regions,were exposed to the O_3 concentrations gradient consisting of low O_3 treatment,non-filtered treatment,100 n L·L- 1and 150 n L·L- 1O_3 by using open-top chambers. [Results]（ 1） the decrease in photosynthesis of the three tree species was related to non-stomatal factors. Elevated O_3 caused a decrease in the degree of correlation between net photosynthetic rate and stomatal con-ductance,reduced the using range of photosynthetically available radiation（ PAR） as a whole,induced obviously the photo inhibition and weakened the photosynthetic acclimation of plants accordingly. The negative effects on Phoebe zhennan and Machilus pauhoi seedlings were more serious with higher O_3 concentration,however,the negative effects of 100 n L·L- 1O_3 on Phoebe bournei were more serious than 150 n L·L- 1O_3. In non-filtered treatment,although the mean O_3 concentration was low,to some extent,O_3 had negative effects on seedlings as a result of its higher peak O_3 concentration. Relative to non-filtered treatment,low O_3 treatment reduced the damage of O_3 by eliminating relative high O_3 peak concentration.（ 2） Under O_3 stress,obvious visible symptoms were found in the three tree species,including chlorosis,macular and necrosis in the leaves of Phoebe zhennan,chlorosis,macular and water stains in the leaves of Phoebe bournei,brown-red spots,water stains,necrosis,crimp and wilt in the leaves of Machilus pauhoi. [Conclusion] Elevated O_3 resulted in the decrease of photosynthesis and visible symptoms in the leaves of the three tree species,and all these species can be used as bioindicators of O_3 pollution. Sensitive degree to O_3 among the three tree species was determined based on photosynthesis： Machilus pauhoi Phoebe bournei Phoebe zhennan. Machilus pauhoi has better indicating effect due to greater O_3-sensitivity and more serious injury symptoms.