Corn rust (Puccinia sorghi – Common Rust; Puccinia polysora – Southern Rust; Physopella zeae – Tropical Rust) represents one of the most economically significant fungal diseases affecting maize (Zea mays) production worldwide, including in Egypt. As an obligate biotrophic pathogen, the rust fungus depends entirely on living host tissue for growth and reproduction. In Egypt, corn rust threatens both summer and winter maize crops, with yield losses ranging from 10–40% in susceptible varieties under favorable conditions. Warm, humid weather and dense plant populations accelerate disease spread dramatically. Unlike soil-borne pathogens, rust spores travel on wind currents over thousands of kilometers, making regional outbreaks unpredictable and difficult to prevent through cultural practices alone.