Journal of Stress Physiology & Biochemistry, Vol. 3, No. 2,
2007, pp. 4- 14
Original Text Copyright (cc) 2007 by Sudachkova, Milyutina, Romanova
ORIGINAL
ARTICLE
Data source : Google Scholar
QueryDate : 2016-12-24
Cites : 4 + 3
FREE AMINO ACID
COMPOSITION IN SCOTS
PINE TISSUES UNDER STRESS IMPACT IN RHIZOSPHERE
Sudachkova N.E., Milyutina I.L.,
Romanova L.I.
V.N. Sukachev
Institute of Forest SB
RAS, 660036, Krasnoyarsk, Academgorodok Russia e-mail: biochem@ksc.krasn.ru
Received October 16, 2007
Abstract – The free amino acid
content in the needles and the inner
bark of stems and roots of 8-13-ages self-sawn trees of Pinus sylvestris L. in Central
Siberia in experimental and natural conditions was compared. The
experiments imitated an influence of long-seasonal or permafrost, soil
drought and root hypoxia, concomitant flooding. The aim of the
investigation was to expose the adaptive changes of these metabolites
composition under stress impact. All of types of stress influences
changed the total free amino acid content in the tissues of different
morphological tree parts: the cooling of root system caused a deposit
of free amino acids in overground tree part, the water deficit
stimulated an accumulation of free amino acids in root inner bark, the
flooding decreased the amino acid content in all tissues. The ratio in
a group of amino acids with glutamic acid as metabolic precursor
(-aminobutyric (GABA),
proline, arginine, citrulline and ornithine) changed under different
stress impact. The cold stress in rhizosphere caused GABA accumulation
in the needles and stem but not in the roots in the period of soil
thawing. The moderate moisture deficit had not an influence on GABA
content, the flooding caused GABA accumulation only in new needles. The
maximal exceeding above control were marked for the sum of arginine and
its metabolic precursors citrulline and ornithine. The group of these
compounds may be considered as stress metabolites for scots pine, but
specificity of depositing of these amino acids at water stress requires
additional proofs. Since the proline accumulation was showed in
separate times in the different tissues under all of investigated
stressors impact, the specificity of proline as indicator of water
stress in scots pine tissues is debatable. The disturbance of
donor-acceptor connections in experiment with cooling resulted to the
amino acid accumulation in stem inner bark, in experiment with drought
– in root inner bark.
Key
words:
drought, flooding, cooling, free amino acids, scots pine
