Agriculture Reference
In-Depth Information
Chapter 6
Overlapping Horizons of Salicylic
Acid under Different Stresses
Mohd Irfan, Shamsul Hayat, Arif Shafi Wani and Aqil Ahmad
1 Introduction
Since the discovery of salicylic alcohol, isolated as a glycosidic derivative first by
Johann Buchner in 1928, salicylic acid (SA) has emerged rapidly to establish itself
as a class of ubiquitous phytohormone in plant kingdom. It found its role in regulat-
ing diverse metabolic and physiological functions in plant tissues, particularly in
meristematic and biotically-challenged tissues regulating redox homeostasis. The
derivatives of acetyl salicylic acids have been shown to manage plant's internal me-
tabolism at its optimal growth conditions in different normal and stressed regimes
of soil salinity (Kaydan et al.
2007
; Tari et al.
2004
; Szepesi et al.
2005
; El Tayeb
2005
; Yusuf et al.
2008
), water stress (Senaratna et al.
2000
; Hamada and Al-Hakimi
2001
; Hayat et al.
2008
), high temperature stress (Lopez-Delgado et al.
1998
; Janda
et al.
1999
; Larkindale and Huang
2004
; He et al.
2005
; Chakraborty and Tongden
2005
), chilling (Szalai et al.
2002
; Tasgin et al.
2003
; Korkmaz
2005
), and heavy
metal stresses (Choudhury and Panda
2004
; Panda and Patra
2007
; Krantev et al.
2008
; Guo et al.
2009
; Zhou et al.
2009
). SA regulates the internal oxidative state
of cell(s) quite differently under two types of microbial invasions, i.e. pathogenesis
and symbiosis. In pathogenesis invasion, it synergises reactive (oxygen, nitrogen or
free radical) species, simultaneously cross-talking with other active phytoregula-
tors (e.g. nitric oxide, brassinosteroids jasmonic acids and ethylene, etc.), while in
symbiosis invasion, it suppresses the over-accumulation of reactive radicals acti-
vating detoxification system (antioxidant enzymes and molecules) in co-operation
with different plant hormones (viz., auxins, cytokinins and gibberellic acids, etc.).
“Resistance induced through a wide range of pathogens (Malamy et al.
1990
;
Durner et al.
1997
), via flash/mild abiotic stress (Ashraf et al.
1999
; Azevedo Neto
et al.
2005
), which may be sometimes taxonomically unrelated (Uknes et al. 1992),
facilitates” the accumulation of SA to strengthen resistance at whole plant level.
S. Hayat (
) · M. Irfan · A. S. Wani · A. Ahmad
Plant Physiology Section, Department of Botany, Aligarh Muslim University,
Aligarh 202002, UP, India
