Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.)

To clarify the effects of O-3 on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O-3 at 60 and 100 nl l(-1) (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O-3. Although there was no significant effect of O-3 on stomatal diffusive conductance to H2O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O-3. The sensitivity of growth, yield, yield components and leaf gas exchange rates to O-3 was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O-3 may detrimentally affect wheat production in Bangladesh. (C) 2009 Elsevier Ltd. All rights reserved.