Journal of Stress Physiology & Biochemistry, Vol. 7, No. 4,
2011, pp. 207- 216. ISSN 1997-0838
Original Text Copyright (cc) 2011 by Kharadi, Upadhyaya, Upadhyay and Nayak
Effect of Heavy metal stress on spore germination of Pteris confusa T. G. Walker and Pteris argyraea T. Moore
Irudayaraj V., Johnson M.*, Priyakumari A.S., Janani Prabha A.
Department of Plant Biology and
Plant Biotechnology, St. Xavier’s College (Autonomous), Palayamkottai –
627 002, Tamil Nadu, India
Tel: + 91 97 86 92 43 34; Fax: + 91 462 2561 765
*E-mail: ptcjohnson@gmail.com
Received September 22, 2011
Background: Plants
have both constitutive and adaptive mechanisms for coping with the
elevated metal concentrations and they are utilized to clean the
polluted soil and water. Unlike angiosperms hyperaccumulators, fern
hyperaccumulators are equipped with inherent biological characteristics
that could be exploited in the phytoremediation strategies aimed at
decontaminating polluted sites. Fern spores can be successfully used to
screen the hyperaccumualting ferns and also to test the toxicity of the
metal contaminated samples.
Purpose of the Study: In the present study, a preliminary attempt was made to compare the tolerance capacity of the spores of two ferns; Pteris confusa T. G. Walker and Pteris argyraea
T. Moore against the heavy metal zinc (Zinc sulphate). Spores of the
two ferns were cultured in Knop’s liquid medium with various
concentrations of zinc sulphate (0-200ppm).
Results: In the case of P.
confusa normal germination was observed in control, 120 ppm and 140 ppm
and the germination of spores were failed in 160, 180 and 200 ppm of
zinc supplemented cultures. In contrary, P. argyraea
showed maximum percentage of spore germination in 140 ppm zinc
supplemented cultures and the control and 120 ppm zinc sulphate
supplemented cultures were failed to show the germination. The
germination percentage and growth rate was decreased in high
concentration of zinc sulphate. Rhizoids are showed more tolerance to
heavy metal than protonema of P. argyraea.
Conclusion: Difference in
response of spores to the heavy metal zinc may be due the difference in
the hyper-accumulating capacity of the ferns.
Key words: Zinc Sulphate; Heavy metal; Spore; Stress
