ABSTRACT
A multitude of climatic factors, such as temperature, drought, salinity, and heavy metal toxicity, affect agricultural production. In this respect, to avert a drop in agricultural productivity resulting from climate change, plant breeding innovations and genetic engineering strategies to boost abiotic stress tolerance are important. Biotechnologists have been able to tweak any DNA sequence with excellent accuracy via the latest discoveries in first-generation genome editing techniques such as zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). These strategies, however, are expensive and laborious, since they require complex steps involving protein engineering. Genome editing using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas strategy as a second-generation genome editing system has gained great interest over the last few years as an effective method to create heritable genetic mutations. Using the CRISPR/Cas strategy, a handful of studies have been reported to date on improving abiotic stress resilience in crop plants. In addition, the development of more specialized forms of Cas9 proteins such as Cpf1, dCas9 greatly enhances the flexibility of the CRISPR/Cas system. This chapter focuses on the perspective and promising applications, recent advances, and potential challenges of targeted genome engineering for increased plant tolerance to abiotic stress and productivity.
