Signaling in response to cold stress

Abstract

World population is growing at a fast pace and is projected to reach 6.5 billion by 2050. At the same time, numbers of changes that are occurring in regular environmental parameters are posing threats to the agricultural productivity. Thus, feeding 6.5 mouths would indeed be a huge challenge. Besides the ever-growing human population and alterations in environmental scenarios, reduction in the area of land used for agriculture, declination of crop productivity, overexploitation of bioresources, mal-agricultural practices, and deleterious abiotic environmental stresses are leading to ecological imbalance. To reduce these losses scientists all over the world focus on novel strategies to enhance crop production in order to meet the increasing food demand and establish a balance among different ecological factors. The various abiotic stress conditions such as cold, temperature, drought and salinity cause noxious effects on plant growth and development ultimately affecting the crop productivity. Among various abiotic stresses, cold stress is one of the main environmental stresses that limits the crop productivity and geographical distribution of most valuable crop plants. However, plants show remarkable developmental plasticity to survive in a continually changing environment. Being sessile, plants have generated in the course of their development proficient strategies of tremendous response to elude, tolerate, or adapt to various types of environmental stress conditions including cold. The acclimatization to various abiotic stress factors is largely dependent uponthe activation of cascades of molecular channels involved in stress perception, signal transduction, and the expression of specific stress-related genes and metabolites. Understanding the pathway mechanisms by which plants recognize these stress signals and then transduce them to cellular machinery in order to stimulate adaptive responses is of crucial importance to crop biology. Here we summarize cold stress tolerance mechanism pathways in plants. The main significant points discussed in this chapter include (a) adverse effects of cold stress on plant physiochemical parameters, (b) sensing of cold temperature and involvement of various signal transduction pathways, (c) function of various compatible solutes or osmoprotectants, and (d) types and functions of different cold- responsive genes and transcription factors (TFs) involved in various cold stress tolerance mechanisms.