1 National Institute of
Genetic Engineering and Biotechnology, Tehran, Iran 2 Department of Biology, Faculty of Science, Alzahra
University, Tehran, Iran 1 E-mail: razavi@nigeb.ac.ir 2 E-mail: saboora@alzahra.ac.ir
Received March 10, 2011
Abstract – Potassium, the most abundant cation in plant cells, is
responsible for numerous physiological functions. In saline
environment, similarity of Na+ and K+ causes an unbalance in K+
uptake and disorder in the its functions. In the present research,
changes of four biochemical parameters (proline, glycinebetaine,
photosynthetic pigments and malondialdehyde) have been investigated in Aeluropus lagopoides
seedling under salinity and potassium deficiency. Sterile seeds had
been cultured on modified Murashige-Skoog containing 0, 1.75 or 100 mM
potassium, with or without 600 mM NaCl for 30 days. The results showed
that maximum proline content was observed in root and shoot by 600 mM
NaCl + 1.75 mM K+ treatment. Also in this treatment, amount
of carotenoids and chlorophyll a was more decreased. Potassium
deficiency caused to reduced MDA and chlorophyll b content. The highest
amount of glycinebetaine was measured in the presence of 600 mM NaCl in
the company of 100 mM K+. It can conclude that chlorophyll
oxidation was occurred in K+
deficiency because of increasing lipid peroxidation and disruption of
protein-pigment complexes. The accumulation rates of two osmolite in
different organ was shown that in A.
lagopoides proline and glycinebetaine play more important role
in osmotic adjustment of the shoot and root, respectively.
