Structural and biochemical response of chloroplasts in tolerant and sensitive barley genotypes to drought stress

• Published in: Journal of plant physiology Vol. 207; pp. 61 - 72
• Main Authors: Filek, Maria, Łabanowska, Maria, Kurdziel, Magdalena, Wesełucha-Birczyńska, Aleksandra, Bednarska-Kozakiewicz, Elżbieta
• Format: Journal Article
• Language: English
• Published: Germany Elsevier GmbH 01.12.2016; Elsevier Science Ltd
• Subjects: Adaptation, Physiological; Barley; Barley genotypes; Carotenoids; Chloroplasts; Chloroplasts - metabolism; Chloroplasts structure; Data processing; Degradation; Drought; Drought stress; Droughts; Electrokinetic potential; Electrokinetics; Electron paramagnetic resonance; Electron Spin Resonance Spectroscopy; Genotype; Genotypes; Hordeum - genetics; Hordeum - physiology; Iron; Leaves; Long-lived radicals; Manganese; Metal concentrations; Paramagnetic metal ions; Plant growth; Plant Leaves - cytology; Polarity; Radicals; Raman spectra; Raman spectroscopy; Reference Standards; Seedlings; Seedlings - cytology; Spectrum Analysis, Raman; Stress, Physiological; Stresses; Barley genotypes; Drought stress; Electrokinetic potential; Chloroplasts structure; Paramagnetic metal ions; Long-lived radicals
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2016.09.012

The aim of this research was to characterize the changes of structural organization of chloroplasts of sensitive (Maresi) and tolerant (Cam/B1) barley genotypes upon soil drought (10days), which was applied in two stages of plant growth, i.e. seedlings and flag leaves. The electron paramagnetic resonance (EPR) technique was used for the determination of changes in the concentration and nature of long-lived radicals and metal ions (Mn, Fe), measured directly in the structures of fresh leaves, occurring after stress treatment. Stronger variations of EPR parameters were found after drought stress application in the flag-leaf phase and for sensitive genotype. Chloroplasts of Cam/B1 were characterized by a larger surface area and less degradation of their structure during drought stress in comparison to Maresi. The data obtained from Raman spectra showed that better stress tolerance of the genotype was accompanied by greater accumulation of carotenoids in chloroplasts and was correlated with an increase in carotenoid radicals. The increase of the value of the electrokinetic potential (relative to control), which was slightly larger for the chloroplasts of Maresi than of Cam/B1, indicated the chemical reconstruction of the membrane leading to a reduction of their polarity during drought action.