Precision editing to improve fruit traits: CRISPR/Cas into the picture.

Crop growth, quality, and yield can be adversely affected by various biotic and abiotic stresses. Crop characteristics can be improved with conventional breeding and other variation-based breeding strategies. However, these strategies are time as well as resource consuming and to overcome this, novel approaches are necessary. CRISPR/Cas technique allows to improve desired traits more efficiently and accurately by targeting specific genes. Genome editing has become more versatile with CRISPR/Cas systems and is a valuable tool to protect food security by developing commercial crops optimized for yield and nutritional quality. Researchers are able to target and edit stress response pathway genes to develop crops with increased tolerance to stress. A lack of regeneration protocols and sufficient genome sequencing data has restricted fruit editing to only a few fruits (tomatoes, citrus, apple, kiwi, banana, grapes, strawberries, watermelon, etc.). This review is focused on CRISPR/Cas applications on the nutritional aspects of fruit engineering along with the challenges and opportunities. Another aspect which will be covered is the use of CRISPR/Cas technology to improve fruit resilience to biotic and abiotic stress, but not at the cost of yield. We discuss the pros and cons of using this technology, such as unintended effects on fruit traits or public concerns about GMOs. We conclude that the application of CRISPR/Cas9 technology has the potential to be of great benefit to the agricultural industry not only to improve nutritional aspects but also to help reduce crop losses.