The Oxidative Burst: Roles in Signal Transduction and Plant Stress

Abstract

Higher plants have a stationary life-style and the potential to adapt to physical, chemical, and biological factors to maintain their homeostasis. It is critical for plants to readily recognize dangerous or harmful stress factors and to effect suitable responses to them. Recent developments in molecular biology have made possible the investigation of mechanisms by which plants respond to various stresses. The accumulated knowledge suggests that plants express new genes and establish new metabolic activities depending on the type and strength of the individual stress factors (Lam et al. 1989; Nover et al. 1989; Blechert et al. 1995; Chandra and Low 1995; Doares et al. 1995; Hahlbrock et al. 1995; Pena-Cortes et al. 1995). How plants receive, distinguish, and respond to exogenous environmental factors is of much current interest and investigation. In this chapter, I describe and discuss the oxidative burst (OXB) in plants, which is characterized by a rapid and transient generation of active oxygen species (AOS) immediately after exposure to certain stresses.

All organisms have to overcome the harmful effects of AOS. Plants have acquired an essential system to reduce and scavenge AOS, which are naturally generated during photosynthesis and respiration (Asada 1994). It is of interest to understand the purpose of rapid AOS generation in plants immediately upon being stressed. The AOS seem to play a role in initiating signals for the response to various stresses. Therefore, it is useful to know how plants recognize harmful stresses and effect appropriate responses.

The purpose of this review is to...