Genome editing in grass plants

Cereal crops including maize, rice, wheat, sorghum, barley, millet, oats and rye are the major calorie sources in our daily life and also important bioenergy sources of the world. The rapidly advancing and state-of-the-art genome-editing tools such as zinc finger nucleases, TAL effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated systems (CRISPR-Cas9-, CRISPR-Cas12a- and CRISPR/Cas-derived base editors) have accelerated the functional genomics and have promising potential for precision breeding of grass crops. With the availability of annotated genomes of the major cereal crops, application of these established genome-editing toolkits to grass plants holds promise to increase the nutritional value and productivity. Furthermore, these easy-to-use and robust genome-editing toolkits have advanced the reverse genetics for discovery of novel gene functions in crop plants. In this review, we document some of important progress in development and utilization of genome-editing tool sets in grass plants. We also highlight present and future uses of genome-editing toolkits that can sustain and improve the quality of cereal grain for food consumption.