Chemistry Reference
In-Depth Information
Chapter 7
Endogenous ABA as a Hormonal
Intermediate in the Salicylic Acid
Induced Protection of Wheat Plants
Against Toxic Ions
F. M. Shakirova, M. V. Bezrukova and D. R. Maslennikova
Abstract We have previously suggested that endogenous abscisic acid (ABA)
may play a role of hormonal intermediate in the implementation of the salicylic
acid (SA) induced protection of wheat plants against abiotic stress factors. With
the use of an inhibitor of ABA biosynthesis fluridone there were obtained
experimental arguments in favor of the key role of rapid reversible accumulation
of ABA during the SA-treatment and maintaining elevated levels of ABA in SA-
pretreated seedlings subjected to cadmium stress and salinity in the implementa-
tion of pre-adaptive and protective action of SA on wheat plants, respectively.
Thus, it was detected that pretreatment of wheat seedlings with fluridone prevented
SA-induced accumulation of ABA under normal conditions and maintenance
under stress of increased ABA content in plants pre-treated with SA. This was
manifested in inhibition of SA-induced effects: generation of ROS, activation of
phenylalanine ammonia-lyase and antioxidant enzymes and deposition of lignin in
the cell walls of roots, as well as the accumulation of wheat germ agglutinin,
proline and enhanced transcription of TADHN gene coding for dehydrin that are
making an important contribution to the development of plant resistance to oxi-
dative stress and dehydration. In general, this is reflected in the prevention of SA-
induced wheat resistance to the effects of toxic ions, as judged by the level of
accumulation of MDA, release of electrolytes from the tissues and growth
parameters of wheat seedlings. These data provide strong argument in favor of the
likelihood of implementation of the endogenous ABA as a hormonal intermediate
in triggering the defensive reactions under the influence of SA that form the basis
for the development of SA-induced plant resistance to cadmium stress and sodium
chloride salinity.
Search WWH ::
Custom Search