Potato (Solanum tuberosum L. cv. Kara) was grown in Open‐Top Chambers (OTCs) in Northern Egypt at ambient (ca 350 ppm) or doubled CO 2 (ca 690 ppm) either in charcoal‐filtered air (15 nl l‐1) or in non‐filtered ambient air (78 nll‐1 O 3 ) to investigate the changes in physiology and yield under long‐term elevated CO 2 and/or O 3 throughout 100 days. Ambient O 3 level reduced net photosynthetic rates, number and weight of tubers by 18 per cent, 41 per cent and 21 per cent, respectively, whereas elevated CO 2 caused the opposite effect where it increased the same parameters by 44 per cent, 37 per cent and 20 per cent, respectively. Significant O 3 x CO 2 interactions were detected. However, O 3 caused an increase in GR and POD by 18 per cent and 35 per cent, respectively, while CO 2 caused an increase in POD only by 46 per cent, and there was no effect of O 3 and/or CO 2 on other enzymes. The results of this study are discussed in relation to predicted atmospheric changes.
World Journal of Science, Technology and Sustainable Development – Emerald Publishing
Published: May 1, 2010
Keywords: Open‐Top Chambers; Potato (Solanum tuberosum); O 3 ; CO 2 ; Photosynthesis; Stomatal Conductance; Antioxidant enzymes; Superoxide Dismutase; Glutathione Reductase; Ascorbate Peroxidase; APX; Guaiacol peroxidase