臭氧胁迫下白蜡与银杏幼苗的响应差异

Differences in the responses of Fraxinus chinensis and Ginkgo biloba seedlings to ozone stress

为了明确大气臭氧(O_(3))浓度升高对木本植物的生长、生理生化特征的胁迫效应,本研究利用开顶式气室(OTC),以典型绿化植物白蜡(Fraxinus chinensis)和银杏(Ginkgo biloba)幼苗为研究对象,研究了3个臭氧浓度水平(环境浓度,AA;环境浓度+40 nmol·mol^(-1),AA+40;环境浓度+80 nmol·mol^(-1),AA+80)下白蜡和银杏的叶片数量、叶片面积、生物量、光合速率、碳水化合物和非结构性碳水化合物的变化差异。结果表明,累积熏蒸35、51 d和71 d后,对比AA试验组,AA+40和AA+80浓度O_(3)抑制了白蜡幼苗的叶片数量和叶面积生长,而促进了银杏幼苗的叶片数量和叶面积生长,并促进了白蜡的光合速率;AA+40和AA+80浓度臭氧均抑制了白蜡和银杏幼苗的叶片非结构性碳水化合物的含量和生物量。O_(3)浓度升高和臭氧熏蒸时间延长,对白蜡和银杏幼苗的叶片生长、光合速率和非结构性化合物累积整体呈抑制,但存在银杏叶片生长和白蜡光合速率受到不同程度促进的情况。O_(3)浓度升高会对白蜡、银杏幼苗的生长和光合作用产生胁迫,其中白蜡的叶片生长状态对O_(3)胁迫更敏感,银杏的光合速率对O_(3)胁迫更敏感。

In order to clarify the stress effects of increasing atmospheric ozone(O_(3))concentration on the growth,physiological,and biochemical characteristics of woody plants,an open-top chamber(OTC)was used to study the differences in leaf quantity,leaf area,biomass,photosynthetic rate,carbohydrates,and non-structural carbohydrates between typical green plant Chinese ash(Fraxinus chinensis)and ginkgo(Ginkgo biloba)seedlings under three ozone concentrations(environmental concentration,AA;environmental concentration+40 nmol·mol^(-1),AA+40;environmental concentration+80 nmol·mol^(-1),AA+80).The results showed that after cumulative fumigation for 35 days,51 days,and 71 days,compared with AA experimental treatment,the leaf number and leaf area growth of the Chinese ash seedlings were inhibited,while the photosynthetic rate of Chinese ash seedlings and the leaf number and leaf area growth of ginkgo seedlings were promoted under AA+40 and AA+80 experimental treatments.The nonstructural carbohydrate content and biomass of Chinese ash and ginkgo seedlings were also inhibited under AA+40 and AA+80 experimental treatments.The leaf growth,photosynthesis rate,and accumulation of unstructured compounds were inhibited in Chinese ash and ginkgo seedlings under elevated O_(3) concentrations and prolonged ozone fumigation time,but the leaf growth of ginkgo and photosynthesis rate of Chinese ash were promoted by O_(3) to different degrees.Increases of O_(3) concentration cause stress on the growth and photosynthesis of Chinese ash and ginkgo seedlings,and the leaf growth state of Chinese ash and the photosynthesis rate of ginkgo show greater sensitivity to O_(3) stress.