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Effect of salt stress on
growth, inorganic ion and proline accumulation in Thai
aromatic rice, Khao Dawk Mali 105, callus culture
Summart, J.1,
Thanonkeo, P.2*, Panichajakul, S.2,
Prathepha, P.3 and McManus, M. T.4
1Department
of Biotechnology, Graduate School, Khon Kaen University,
Khon Kaen 40002, Thailand.
2Department
of Biotechnology and Fermentation Research Center for Value
Added Agricultural Products (FerVAAP), Faculty of
Technology, Khon Kaen University, Khon Kaen 40002, Thailand.
3Department
of Biotechnology, Faculty of Technology, Mahasarakham
University, Mahasarakham 44000, Thailand.
4Institute
of Molecular Bio Sciences, Massey University, Private Bag
11222, Palmerston North, New Zealand.
*Corresponding author.
E-mail:
portha@kku.ac.th.
Tel.: +66-43-362121. Fax: +66-43-362121.
Accepted 26 March, 2009 |
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The inhibitory effect of salt stress in rice is complex and
is one of the main reasons for reduction of plant growth and
crop productivity. In the present study, the response of
rice callus cultivar Khao Dawk Mali 105 (KDML105), commonly
known as Thai jasmine rice, to salt stress was examined.
Callus cultures of KDML105 rice were exposed to salt stress
by placing on Murashige and Skoog (MS) medium containing 250
mM NaCl. Growth, water content, proline and inorganic ion
content in rice cells were measured during stress treatment
for 8 - 10 days. After prolonged exposure to salt stress,
growth and water content of rice cells were progressively
decreased. Rice cells accumulated high level of Na+
during stress, whereas the accumulation of K+ and
Ca2+ was decreased. High level of Na+
inside the cells inhibited the K+ uptake resulted
in increase level of the Na+/K+ ratio.
In addition, salt stress also caused an increase in the
accumulation of proline. This result suggested that proline
may play a crucial role in protecting the KDML105 rice cells
under salt stress.
Key
word:
Aromatic rice, osmoprotectant, callus culture, salt stress. |
