Bakanae disease of rice: Integrating pathogen biology with advanced genomic solutions for durable resistance

Abstract

Bakanae disease caused by Fusarium fujikuroi had arisen as a prominent biotic restraint limiting rice production. Due to production of poor grain quality seed as well as yield losses, it resulted in major economic losses. This disease has been reported from prominent rice-growing regions around the globe. Early seedling symptoms encompass elongation, chlorosis, and decreased vigor. In the later growth stages, symptoms intensify and consist of basal rot, aberrant tillering, and finally plant mortality. Roots or wounds constitute the initial trigger for an infection, which is then followed by colonization and the production of toxic substances, primarily fumonisins, which promote the further disease progression. Temperature and humidity are key environmental factors that influence the incidence and intensity of disease. Identification of resistant germplasm, including landraces, traditional varieties, and wild relatives, presents good resources for standard breeding programs complemented by reliable screening technologies. Conventional breeding methods have demonstrated to be inefficient owing to the intricacy of resistance and pathogen variability. The latest developments in modern breeding, which include genomics, QTL mapping, marker-assisted selection, and gene-editing technologies (CRISPR/Cas systems) have paved up new possibilities to produce resistant cultivars. The integration of resistant cultivars with cultural, chemical, and biological inhibition measures remained paramount for effective disease management.