ABSTRACT
Plant pathogens including bacteria, fungus and viruses significantly reduce global productivity. Plant pathologists’ focus has been switched to host susceptibility factors as a result of the evolution of resistance in infections brought on by targeting the dominant R gene (or S genes). Due to its complexity, the initial generation of genome editing technology is being replaced. The CRISPR-Cas9 system has revolutionized targeted genome editing technology because of its ease of use and low cost. The CRISPR-Cas9 system has been used to build resistance against bacteria, fungi, and viruses. Different regions of the viral genome have been temporarily targeted, as well as through the development of transgenic plants, to increase resistance to DNA viruses (mostly single-stranded DNA viruses). Targets for RNA viruses have mostly included the host susceptibility factors and, more recently, the viral RNA genome itself. The production of transgenic has primarily been used to target the host susceptibility genes in order to generate fungal and bacterial resistance. Despite these achievements, the CRISPR-Cas9 technology has off-targeting problems. The ongoing discovery and evolution of new variations are addressing this issue. Finally, the fate of using this adaptable technology to breed pathogen resistance in crop plants will depend on the regulatory perspective on CRISPR-Cas9.
