Single-Gene Versus Multigene Transfer Approaches for Crop Salt Tolerance

Abstract

Plants face many challenges during biotic and abiotic stresses during their lifetime. Salinity stress is the most typical abiotic stress and combines water stress and ionic stress. It affects plants in many aspects at the molecular, cellular, and morphological levels. In response and adaptation to salt stress, plant gene regulation is modulated at the transcriptional or post-transcriptional level. Efforts have been made to overcome salinity by traditional approaches such as breeding, priming, and modern techniques of genetic engineering. However, because salt tolerance depends on multigenic properties, it is hard to control this problem simply by a single gene transfer. Although the response and signaling mechanisms of plants under salt stress have not been completely elucidated, thorough understanding of the salt stress response in plants has enabled scientists to make transgenic plants showing salt tolerance, mostly by a single transfer but also by multigene transfer. In addition to a purely gene-based approach, epigenetics and noncoding RNA have been found to play roles in salt stress/tolerance in plants. This chapter provides a brief introduction to salt stress responses and strategies for salt tolerance in plants. Moreover, single-gene versus multigene transfer and/or regulation of salt tolerance in plants are described.