Fungicide selection and timing to manage southern rust of corn

Foliar corn diseases are among the most important yield-limiting factors that affect commercial corn production in the Mid-South. Southern rust is caused by the fungus Puccinia polysora, which only infects corn and is reintroduced each year from the tropic regions of Central America and the Caribbean. Symptoms consist of small orange pustules that are often first detected on leaves located in the mid- to upper-canopy. As conditions favor disease development initial infections produce spores that are spread to nearby plants and nearby fields resulting in secondary infections and the spread of southern rust