RespxAzolla Plants (Azolla pinnata and Azolla filiculoides) Exposed to UV-B


Effect of ultravilolet-B (0.4 Wm−2) irradiation on growth, flavonoid content, lipid peroxidation, proline accumulation and activities of superoxide dismutase and peroxidase was comparatively analysed in Azolla pinnata and Azolla flliculoides. Growth measured as increment in dry weight reduced considerably due to all UV-B treatments. However, the reduction was found to be severe in A. flliculoides as compared to A. pinnata. The level of UV-absorbing compound flavonoids increased significantly in A. pinnata plants whereas only a slight increase in the flavonoid content was observed in A. flliculoides. UV-B exposure led to enhanced production of malondialdehyde (MDA) and electrolyte leakage in A. flliculoides than A. pinnata. Proline accumulation also showed a similar trend. Marked differences in the activity of antioxidant enzymes such as superoxide dismutase (SOD) and peroxidase (POD) was noticed in both the plants exposed to UV-B. Our comparative studies indicate A. pinnata to be better tolerant to UV-B as compared with A. flliculoides which appears to be sensitive.


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We are grateful to University administration and Council of Scientific and Industrial Research, New Delhi India for providing necessary laboratory facilities and financial assistance.

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Correspondence to G. Abraham.

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Masood, A., Zeeshan, M. & Abraham, G. RespxAzolla Plants (Azolla pinnata and Azolla filiculoides) Exposed to UV-B. BIOLOGIA FUTURA 59, 247–258 (2008).

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  • Azolla pinnata
  • Azolla filiculoides
  • flavonoids
  • growth
  • lipid peroxidation
  • proline
  • peroxidase
  • superoxide dismutase