Shallu Thakur, Simranjot Kaur, Sudeep Adhikari, P. S. Sabharwal, Yuqing Fu, Geoffrey Meru
In plants, resistance genes (R) are key players in combatting diseases caused by various phytopathogens. Typically, resistance relies on detecting a single pathogen-derived molecular pattern. However, R-gene-mediated resistance is often race specific, follows the gene-for-gene hypothesis, and can be overcome in field conditions as pathogens evolve. On the contrary, altering plant susceptibility genes (S-genes) facilitates compatibility and results in broad and durable resistance. S-genes are negative regulators present in plants and exploited by pathogens to facilitate their growth and cause infection. Several studies across crop species have reported manipulation of S-genes using genome editing to confer broad spectrum resistance. This review focuses on the plant defense mechanism against biotic stress, R-genes vs. S-genes, different types/classes of S-genes, different tools for S-gene discovery, and the use of gene editing technologies to target S-genes in addition to their applications, challenges, and future perspectives.