CRISPR-Cas9 genome editing of crops: Food and nutritional security

The United Nations established the goal of achieving global food security by 2030 as one of its top sustainable development goals in 2015. The current agricultural harvest is insufficient to accomplish the zero-hunger objective and feed the world's growing population. It would require more extensive and consistent crop production. Gene-editing technologies have recently emerged as viable alternatives to permit precise modifications in genomes with increased efficiency and yield higher agricultural productivity. Due to their simplicity, adaptability, and reproducibility across a diverse variety of species, genetic engineering techniques like CRISPR-Cas9 have become quite prominent. CRISPR-Cas9 gene-editing technology can improve crop yields, quality, stress resistance, food safety, nutritional security, and shelf-life, reduce antibiotic resistance, and hasten plant domestication. Cutting-edge techniques like genome editing (GE) allow for the precise introduction or mutation of specified genes into plant genomes. The advent of programmable nucleases like CRISPR-Cas9 has improved gene editing and potentially improved food production and nutritional security. Knock-out, knock-in, gene activation, gene repression, nuclear rearrangements, base editing, molecular breeding, and epigenome engineering are just a few ways that CRISPR systems can target and change genes. For novel applications in plant genetic engineering, CRISPR-Cas systems can be repurposed for GE toward de-novo speciation; mitochondrial and plastid genome engineering toward enhancing photosynthesis, submergence, and drought tolerance. The versatility of CRISPR-associated systems broadens the scope of crop development applications that they can be used for, especially in improving food and nutritional security, which is the focus of this chapter.