Journal of Stress Physiology & Biochemistry, Vol. 7, No. 4,
2011, pp. 157- 174. ISSN 1997-0838
Original Text Copyright (cc) 2011 by Deivanai, Xavier, Vinod, Timalata and Lim
Role of Exogenous Proline in Ameliorating Salt Stress at Early Stage in Two Rice Cultivars
Deivanai S, R. Xavier, V. Vinod, K. Timalata and O.F. Lim
Department of Biotechnology, Faculty of Applied Sciences, AIMST University, Semeling Campus, 08100 Bedong, Kedah, Malaysia
E-mail: deivanai@aimst.edu.my
Received September 12, 2011
The study evaluated the
effect of proline on germination and seedling growth of two Malaysian
rice cultivars (MR220 and MR232) under salt stress. The exposure
of rice seeds to increasing concentration of NaCl (0, 100, 200, 300 and
400 mM) had drastically affected germination (%), root and shoot length
(mm), chlorophyll content and protein content. It is evident from the
result of inhibition in germination rate, reduction in root and shoot
length, chlorophyll content and protein content. However, several
studies have shown that exogenous application of proline has
ameliorated the negative effect of salt stress by regulating cellular
osmotic balance. The present study has demonstrated that rice seeds
pretreated with proline (1mM, 5mM and 10mM) and grown at different NaCl
concentrations counteracted the adverse effect of salt. Pretreatment of
proline at a concentration of 1mM was found to be effective and
stimulated cellular activities, whereas 10mM proline was ineffective in
improving plant growth under high level of salt (300 and 400mM NaCl).
Key words: Salt stress, exogenous proline, seed germination, seedling growth, rice
