Understanding and enhancing rice resistance to false smut disease

Flower-infecting fungi have caused many economically important diseases in crop production. The fungal pathogen Ustilaginoidea virens infects developing rice florets, causing false smut disease, which leads to reduced grain yield and quality, as well as contamination with mycotoxins that pose hazards to human health and food security. To ensure rice production, substantial efforts have been made on understanding the interaction between rice and U. virens. In this review, we summarize the current understanding of rice resistance mechanisms to U. virens. We discuss the evaluation of false smut resistance, quantitative resistance loci, potential defense strategies of rice panicles, pathogen effector-driven identification of resistance-related genes, and engineering of false smut resistance. We conclude by proposing an integrated defense system that includes disease avoidance, immune response, metabolic adaptation, and the inhibition of susceptibility factors. Furthermore, we outline four critical stages of interaction between rice and U. virens that are essential for understanding and enhancing organ-specific rice resistance to false smut disease.