Strategies for drought tolerance in xerophytes

Abstract

Almost 35% of the Earth’s land surface is covered by desert ecosystems. Areas that suffer from water scarcity are expected to increase owing to global climate changes. Water deficiency has become a worldwide threat due to its lethal effect on plant growth, development, and reproduction which foreshadows a food problem and enormous economic losses. Xerophytes, drought-tolerant plants, are able to grow and live under these harsh conditions. Although xerophytic plants are not closely related taxa, they all have similar forms, structures and shape to survive in such a xeric habitat. Xerophytes and their different mechanisms of adaptation to arid region have become of an international focus nowadays. This chapter discusses frontier knowledge about morphological, anatomical, and physiological adaptations and strategies of survival enabling xerophytes to develop and complete their life cycles in arid and semiarid regions. In addition, a special interest is given to the transcriptomic analysis of xerophytes to reveal the molecular basis for their drought tolerance. Finally, we provide an overview on the importance of xerophytes as a treasure of genetic resources for genetic enhancement of stress resistance of important forage and crop species in areas of arid climate.