Abstract: In order to study the effects of increasing surface ozone(O3) concentrations on the growth and yield of winter wheat in Nanjing area,the winter wheat(Triticum aestivum cv) was grown in top-open field chambers and exposed to treated and non-treated ambient air during the whole life cycle.There were three control groups and the wheat was followed by exposing to unfiltered air(CK),and two treatments with ozone concentration with 100nL/L and 150nL/L(CF100 and CF150)respectively.Each of the treatments was repeated for three times.The results showed that the increasing of ozone concentration caused the change of growing period and the plant premature aging,while the grain filling stage shortened and the growth period shortened either.The height,dry weight and the leaf area of the wheat were all obviously declined(p<0.05),while the decline rate of the CF150 treatment was with 10.01%,36.56% and 29.17% respectively.The number of ears of wheat,ear length,grains per spike and the yield per unit area significantly declined(p<0.05),while the yield per unit area in the CF100 and CF150 treatment declined by 16.11% and 39.17% respectively,compared to control.

Key words: Increasing surface ozone(O3) concentrations, Increasing surface ozone(O3) concentrations, Winter wheat, Yield, Nanjing area