Options for tackling pathogen resistance by genome editing in rice

Abstract

Abstract Rice is the most important staple crop in the developing world and its productivity is critical for food security, development, and poverty elimination. Worldwide, approximately 900 million people from low-income households depend on rice. Ninety percent of the global rice is produced in Asia, mainly by small-scale producers who farm 0.4 ha or less. Productivity is increasingly threatened by biotic stresses from viruses, bacteria, fungi, nematodes, insects, and arachnids. Nowadays, genome editing provides unique opportunities to generate variants of elite lines that are resistant to one or multiple diseases. We provide examples in which the simplest form of genome editing is used to block pathogens from exploiting host susceptibilities, thereby creating a robust broad-spectrum resistance. We highlight the editing of promoter sequences of rice SWEET sugar transporters, which led to resistance against Bacterial leaf blight (BLB) as a blueprint for the use of new breeding technologies in fighting other important crop diseases and for stacking with other useful traits. Notably, successful strategies for protecting against pathogen infections require more than just resistant rice lines, but also better maintenance and strategies to improve the living standards of small-scale producers.