Salicylic Acid Biosynthesis and Role in Modulating Terpenoid and Flavonoid Metabolism in Plant Responses to Abiotic Stress - Salicylic Acid: Plant Growth and Development - page 139

Chapter 8
Salicylic Acid Biosynthesis and Role
in Modulating Terpenoid and Flavonoid
Metabolism in Plant Responses to Abiotic
Stress

T. Tounekti, I. Hernández and S. Munné-Bosch

Abstract Salicylic acid (SA) is a simple phenolic acid with hormonal function
synthesized from the amino acid phenylalanine or chorismate depending on the
plant species, developmental stage and growth conditions. This compound plays a
key role in plant growth and development, and in plant responses to abiotic
stresses such as salinity and drought stress. Under these environmental constraints,
plants synthesize a number of secondary metabolites, including flavonoids and
terpenoids, with a defence-related function. Here, we will discuss the role of SA in
modulating plant responses to abiotic stress, particularly as an inducer of defence
responses against salinity and drought stress. Emphasis will be put on discussing
the SA signalling pathways that affect flavonoid and terpenoid metabolism as
defense compounds against stress.

Keywords Drought stress Salicylic acid Salt stress Terpenoids Flavonoids

1 Introduction

Salycilic acid (SA) or ortho-hydroxy benzoic acid has a broad distribution in the
plant kingdom (Raskin et al. 1990 ). Basal SA levels differ widely among species,
with up to 100-fold differences between plants, even among members of the same
family. For instance, in the Solanaceae, while tobacco contains low basal levels of