Reduced ozone by air filtration consistently improved grain yield in wheat.
This study considered effects of reduced [O(3)] on wheat yield. Open-top chamber charcoal filtered air treatments were compared with non-filtered treatments for field-grown wheat. 30 experiments meeting requirements were found, representing nine countries in North America, Europe and Asia. 26 experiments reported improved yield and 4 experiments reduced yield by filtration, a significant positive effect. Average yield improvement was 9%. Average daytime [O(3)] was reduced by filtration from 35 to 13 nmol mol(-1). Filtration efficiency was 63% for O(3) and 56% for SO(2). For NO(x) it was observed that NO(2) was reduced and NO increased by filtration. Thus, filters convert NO(2) to NO. Most experiments reported low or very low [SO(2)] and [NO(x)]. Thus, O(3) can be concluded to be the main phytotoxic component in the experiments. Elevated [NO(2)] was observed in one experiment. The conclusion is that current [O(3)] over large parts of the world adversely affect wheat yield.
University of Gothenburg, Plant and Environmental Sciences,Göteborg, Sweden. hakan.pleijel@dpes.gu.se
Håkan
H
Pleijel
D000393:Air Pollutants / Q000633:toxicity; D002606:Charcoal / Q000737:chemistry; D005374:Filtration; D009569:Nitric Oxide / Q000009:adverse effects; D009585:Nitrogen Dioxide / Q000009:adverse effects; D010126:Ozone / Q000009:adverse effects*; D013458:Sulfur Dioxide / Q000009:adverse effects; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development*
D000393:Air Pollutants; D013458:Sulfur Dioxide; D002606:Charcoal; D009569:Nitric Oxide; D010126:Ozone; D009585:Nitrogen Dioxide