|HU, YANBO - Northeast Forestry University|
|TIGABU, MULUALEM - Swedish University Of Agricultural Sciences|
|WANG, JUNGHONG - Northeast Forestry University|
|DIAO, JIAN - Northeast Forestry University|
|WANG, KE - Northeast Forestry University|
|YANG, RUI - Northeast Forestry University|
|SUN, GUANGYU - Northeast Forestry University|
Submitted to: Acta Physiologiae Plantarum
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/11/2014
Publication Date: 1/30/2015
Citation: Hu, Y., Bellaloui, N., Tigabu, M., Wang, J., Diao, J., Wang, K., Yang, R., Sun, G. 2015. Gaseous NO2 effects on stomatal behavior, photosynthesis and respiration of hybrid poplar leaves. Acta Physiologiae Plantarum. DOI: 10.1007/S11738-014-1749-8.
Interpretive Summary: Nitrogen air pollutants can affect the plants through chemical reaction, impacting the physiology and biochemistry of plants. Among these pollutants is nitrogen dioxide, precursors for tropospheric ozone, which acts both as a phytotoxin and a greenhouse gas. The mechanisms of how this gas affects the plants are not fully understood. Therefore, investigating the negative impact of nitrogen dioxide on physiology, biochemistry, and morphology in higher plants is important. The study used poplar tree as a model for higher plants. The results showed that net photosynthetic rates were significantly reduced in leaves exposed to 4 microliter per liter of nitrogen dioxide for 48 h when compared with leaves exposed to ambient carbon dioxide of 380 microliter per liter and ambient nitrogen dioxide of 0.1 microliter per liter (the control) and the leaves exposed for 14 h. Respiration rates were dependent on the combined effects of leaf temperature and nitrogen dioxide treatment time. The research demonstrated that nitrogen dioxide negatively impacted the physiology of plants by reducing photosynthesis and respiration rates. This information is important for the scientific communities as it expands our knowledge of the effect of nitrogen dioxide on higher plants.
Technical Abstract: In this study, we used poplar as a model plant and investigated the effects of gaseous nitrogen dioxide (NO2, 4 microliter per liter) on stomatal conductance, photosynthesis, dark- and photorespiration of Populus alba x Populus berolinensis hybrid leaves using the photosynthesis system and scanning electron microscope technique. The results showed that net photosynthetic rates were significantly reduced in leaves exposed to 4 microliter per liter NO2 for 48 h as compared with leaves exposed to ambient carbon dioxide 380 microliter per liter and ambient NO2 less than 0.1 microliter per liter (the control) and the leaves exposed for 14 h. The decline of net photosynthetic rate was caused mainly by NO2 treatment. Dark respiration rates were dependent on co-action of the two factors (leaf temperature and NO2 treatment time). Postillumination carbon dioxide burst in the exposed leaves occurred at 13–15 s after turning the light off, whereas this phenomenon was absent in the control leaves.