Effects of Low Concentrations of Ozone (O3) on Metabolic and Physiological Attributes in Wheat (Triticum Aestivum L.) Plants
Laila A. Baqasi1,2, Huda A. Qari1,2, Nihal Al-Nahhas3, Reem H. Badr3, Wafaa K. Taia3, Rehab A. El-Dakak3 and Ibrahim A. Hassan2,31Department of Biology, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
2Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, 21589 Jeddah, Saudi Arabia.
3Department of Botany, Faculty of Science, Alexandria University, 21589 El Shatby, Alexandria, Egypt.
Corresponding Author E-mail: ihassan_eg@yahoo.com
Abstract: Growth, yield, protein content, net photosynthetic rates, stomatal conductance and amino acid profiles were determined in wheat (Triticum aestivum L) plants in response to 50 ppb O3 during the growing season. This concentration is similar to the concentrations of O3 in ambient air. O3 decreased photosynthetic rates (24%) and stomatal conductance (25%), which were reflected in lower growth and yield in terms of number of grains and 100 grain weight. Scanning electron microscopy showed a collapse in the epidermal cells adjacent to stomata that led to stomatal closure and consequently reductions in stomatal conductance. The significance of O3-induced impairment of growth, yield and alteration in amino acid contents are discussed. To the best of our knowledge, this is the first study reporting impact of ozone on protein content, amino acids and yield of wheat in Saudi Arabia.
Keywords: Growth; Ozone; Physiology; Wheat; Yield Back to TOC