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Does exogenous application of ascorbic acid modulate growth, photosynthetic pigments and oxidative defense in okra (Abelmoschus esculentus (L.) Moench) under lead stress?

  • Iqbal HussainEmail author
  • Asif Siddique
  • Muhammad Arslan Ashraf
  • Rizwan Rasheed
  • Muhammad Ibrahim
  • Muhammad Iqbal
  • Sobia Akbar
  • Muhammad Imran
Original Article

Abstract

Seed priming increases tolerance of plants against various environmental stresses. Although ample literature is available that depicts the beneficial effects of priming under different environmental stresses, the information on induction of tolerance to Pb stress through seed priming with ascorbic acid (AsA) is limited. Therefore, this study was performed to examine the effect of seed priming with AsA (50 and 100 mg L−1), hydropriming and without priming (control) on physiochemical processes of okra cultivars (Subz-Pari and Arka Anamika) under Pb stress (0, 100 mg L−1). Pb stress caused a considerable decline in plant growth and photosynthetic pigments. Contrarily, Pb stress exhibited rise in the contents of total amino acids, free proline, total soluble proteins and AsA. The POD, CAT, and SOD activities were recorded highest at 100 mg L−1 of Pb. Moreover, Pb stress markedly increased H2O2 and MDA levels that triggered oxidative stress. However, plants raised from seed primed with AsA and water exhibited better growth and had higher chlorophylls, free proline, total proteins, total amino acids, AsA and activities of enzymatic antioxidants. Priming with AsA (50 mg L−1) induced better tolerance to Pb stress in okra plants. Plants of cv. Arka Anamika exhibited greater tolerance to Pb than that of cv. Subz-Pari as was evident from higher plant fresh and dry masses.

Keywords

Antioxidant enzymes Chlorophyll pigments Growth Ascorbic acid Metals Lipid peroxidation Okra 

Notes

Acknowledgements

This study was partly supported by the Grants from the Punjab Higher Education Commission (PHEC), Lahore, Pakistan.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2017

Authors and Affiliations

  1. 1.Department of BotanyGovernment College UniversityFaisalabadPakistan
  2. 2.Department of Environmental Life Sciences, Graduate School of Life SciencesTohoku UniversitySendaiJapan
  3. 3.Department of Applied Chemistry and BiochemistryGovernment College UniversityFaisalabadPakistan
  4. 4.Department of ChemistryGhazi UniversityDera Ghazi KhanPakistan

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