Elevated ozone concentration decreases whole-plant hydraulic conductance and disturbs water use regulation in soybean plants
Elevated ozone concentration decreases whole-plant hydraulic conductance and disturbs water use regulation in soybean plants
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臭氧浓度升高会降低整株植物的导水率并扰乱大豆植物的用水调节
DOI：
10.1111/ppl.12673
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发表时间：
2018
影响因子：
6.4
通讯作者：
Hao Guang You
中科院分区：
文献类型：
--
作者：
Zhang Wei Wei;Wang Miao;Wang Ai Ying;Yin Xiao Han;Feng Zhao Zhong;Hao Guang You
对流层臭氧 (O3) 浓度升高已被证明会影响植物性能的许多方面，包括对叶片光合作用和植物生长的有害影响。然而，尚不清楚这种变化是否伴随着植物水力结构和水关系的伴随反应，这将对植物在不利的水条件下的生长和生存产生重大影响。将中国东北地区常用的大豆 (Glycine max(L.) Merr.) 品种暴露在六个开顶室中的未过滤空气（NF，平均 24.0 nl l−1）和升高的 O3 浓度（eO3，40 nl l−1，提供 NF 空气）中 50 天。 eO3处理导致全株水力导度显着降低，这主要是由于根系和小叶的水力导度降低，而茎和叶柄水力导度对eO3没有显着的响应。在 eO3 下生长的植物的气孔导度在上午中旬较低，但在中午显着较高，这导致每日最低水势负值大幅增加。此外，从 eO3 处理过的植物上切下的叶子显示出明显更高的失水率，表明当供水受阻时，其保留水分的能力较低。我们的结果表明，除了 eO3 对光合碳同化产生直接有害影响外，它对水力结构和水关系的影响还可能通过恶化不利水条件的有害影响，对 O3 敏感作物产生负面影响。
Elevated tropospheric ozone (O3) concentration has been shown to affect many aspects of plant performance including detrimental effects on leaf photosynthesis and plant growth. However, it is not known whether such changes are accompanied by concomitant responses in plant hydraulic architecture and water relations, which would have great implications for plant growth and survival in face of unfavorable water conditions. A soybean (Glycine max(L.) Merr.) cultivar commonly used in Northeast China was exposed to non‐filtered air (NF, averaged 24.0 nl l−1) and elevated O3concentrations (eO3, 40 nl l−1supplied with NF air) in six open‐top chambers for 50 days. The eO3treatment resulted in a significant decrease in whole‐plant hydraulic conductance that is mainly attributable to the reduced hydraulic conductance of the root system and the leaflets, while stem and leaf petiole hydraulic conductance showed no significant response to eO3. Stomatal conductance of plants grown under eO3was lower during mid‐morning but significantly higher at midday, which resulted in substantially more negative daily minimum water potentials. Moreover, excised leaves from the eO3treated plants showed significantly higher rates of water loss, suggesting a lower ability to withhold water when water supply is impeded. Our results indicate that, besides the direct detrimental effects of eO3on photosynthetic carbon assimilation, its influences on hydraulic architecture and water relations may also negatively affect O3‐sensitive crops by deteriorating the detrimental effects of unfavorable water conditions.