Southern corn rust caused by Puccinia polysora Underw: a review

Southern corn rust (SCR) caused by Puccinia polysora Underw is one of the most devastating maize diseases, resulting in substantial yield losses worldwide. The pathogen is an obligate biotrophic parasite that is difficult to culture on artificial media. In recent years, the disease has become prevalent—both globally and in China—and increasing difficult to control because of its wide distribution, long-distance migration, multiple physiological races and fast evolution, all of which have contributed to a considerable increase in the risks of associated epidemics. In this review, we summarize the current knowledge of P. polysora, with emphasis on its global distribution (particularly in China), life and disease cycle, population genetics, migration, physiological races, resistance genes in maize and management. Understanding the underlying factors and processes in SCR epidemics should facilitate management of the disease and breeding for resistant maize varieties.