Viral threats to maize: understanding host-virus interactions and sustainable management

Abstract

Viral diseases represent one of the most serious constraints to global maize production, where increasing disease incidence and expanding viral diversity threaten yield stability and food security. Several viruses are recognized as the most economically important pathogens in maize. Maize-infecting viruses employ sophisticated infection strategies that suppress host immunity, manipulate hormonal and redox signaling, and exploit insect vectors to drive rapid and widespread transmission. Synergistic interactions among some co-infecting viruses further intensify disease severity, frequently leading to devastating epidemics. In this review, we highlight the top 10 economically significant maize viruses and summarize key profiles for each. We highlight recent advances in understanding how maize viruses modulate host defenses through RNA-silencing suppressors and regulatory networks involving microRNAs (miRNAs) and reactive oxygen species (ROS) homeostasis. We also discuss progress in diagnostics and genetic tools, including portable detection platforms, next-generation sequencing, CRISPR-based assays, and virus-derived vectors, which are enhancing disease surveillance. Finally, we summarize current control strategies, with an emphasis on RNA interference (RNAi)-based and biotechnology-mediated resistance, and outline critical research gaps concerning resistance mechanisms, vector biology, and viral synergism.