Effects of ozone on zinc and cadmium accumulation in wheat – dose–response functions and relationship with protein, grain yield, and harvest index
Article first published online: 16 NOV 2012
© 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Ecology and Evolution
Volume 2, Issue 12, pages 3186–3194, December 2012
How to Cite
Ecology and Evolution 2012; 2(12): 3186–3194
- Issue published online: 13 DEC 2012
- Article first published online: 16 NOV 2012
- Manuscript Accepted: 6 OCT 2012
- Manuscript Revised: 3 OCT 2012
- Manuscript Received: 3 JUL 2012
- Biodiversity and Ecosystem Services in a Changing Climate
- dose–response function;
- open-top chamber;
Response functions for the effect of ozone on cadmium (Cd) (toxic to humans) and zinc (Zn) (essential nutrient for plants and humans) in wheat grain were derived for the first time. Data from four open-top chamber (OTC) experiments with field-grown wheat, performed in southwest Sweden, were used. Ozone exposure was expressed as the phytotoxic ozone dose above a threshold of 6 nmol/m2 per sec (POD6), and AOT40. Grain Zn concentration was significantly enhanced by ozone, while Zn yield was not affected. The positive ozone effect on grain Zn concentration was almost twice as large as the corresponding effect on grain protein concentration, most likely as a result of nitrogen availability being more limiting than Zn availability. Cd concentration was unaffected by ozone, but Cd yield was significantly negatively affected. For the variables studied, correlation was stronger with POD6 than AOT40, but in several cases, for example, for Zn concentration and Cd yield, there was practically no difference in the performance between the two exposure indices. From the literature, it is obvious that ozone has important adverse effects on wheat yield and certain quality traits. As shown in this study, there are also examples of ozone leading to improved quality, for example, in terms of enhanced Zn concentration of wheat grain. While OTC enclosure did not affect Zn accumulation in wheat grain, Cd accumulation was significantly positively affected, most likely through transpiration being enhanced by the OTC environment, promoting Cd uptake and transport through the plant.