Differential responses of peach (Prunus persica) seedlings to elevated ozone are related with leaf mass per area, antioxidant enzymes activity rather than stomatal conductance. (August 2017)

• Record Type: Journal Article
• Authors: Dai, Lulu; Li, Pin; Shang, Bo; Liu, Shuo; Yang, Aizhen; Wang, Younian; Feng, Zhaozhong
• Is Part Of: Environmental pollution. Volume 227(2017)
• Page Start: 380
• Page End: 388
• Publication Date: 2017-08
• Subjects: Ozone -- Prunus persica -- Leaf mass per area -- Antioxidant defense -- Stomatal conductance; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2017.04.068
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: To evaluate the ozone (O3 ) sensitivity among peach tree ( Prunus persica ) cultivars widely planted in Beijing region and explore the possible eco-physiological response mechanisms, thirteen cultivars of peach seedlings were exposed to either charcoal-filtered air or elevated O3 (E-O3, non-filtered ambient air plus 60 ppb) for one growing season in open-top chambers. Leaf structure, stomatal structure, gas exchange and chlorophyll a fluorescence, photosynthetic pigments, antioxidant defense system and lipid peroxidation were measured in three replicated chambers. Results showed that E-O3 significantly reduced abaxial epidemis thickness, but no effects on the thicknesses of adaxial epidemis, palisade parenchyma and spongy parenchyma. Stomatal area, density and conductance were not significantly affected by E-O3 . E-O3 significantly accelerated leaf senescence, as indicated by increased lipid peroxidation and more declines in light-saturated photosynthetic rate and pigments contents. The reduced ascorbate content (ASC) was decreased but antioxidant enzyme activity (CAT, APX and SOD) and total antioxidant capacity (TAC) were significantly increased by E-O3 among cultivars. The cultivars with visible symptoms also had more reductions in net photosynthetic rate than those without visible symptoms. Ozone sensitivity among cultivars was strongly linked to leaf mass per area (LMA), antioxidant enzymes activity e.g. SOD, APX rather than stomatal parameters (stomatal area, density and conductance) and ASC. Results could provide a theoretical basis for selecting and breeding the ozone-resistant cultivars of peach trees grown in high O3 -polluted regions. Graphical abstract: Highlights: Effects of O3 on the peach were firstly investigated in China. The white peach cultivars were more sensitive to O3 than nectarine cultivars. O3 sensitivities among cultivars are not related with stomatal traits. LMA and antioxidant enzyme activity contribute to O3 sensitivities among cultivars. Abstract : Leaf mass per area and antioxidant enzymes activity contributed to the O3 sensitivities among cultivars.