Development of Southern Rust on Maize at Different Stages of Maturity. S. B. King, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture and Department of Plant Pathology and Weed Science, Mississippi State University, Mississippi State 39762. G. E. Scott, Research Agronomist, Agricultural Research Service and Department of Agronomy, Mississippi State University. Plant Dis. 66:477-481. Accepted for publication 10 July 1981. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1982. DOI: 10.1094/PD-66-477.

Southern rust caused by Puccinia polysora is a potentially serious disease of maize (Zea mays) in the United States, particularly on late plantings of maize in the South. This report describes rust severity on leaves of susceptible maize at successive times in the season on plants of staggered planting dates. Susceptibility of lower leaves to P. polysora did not vary significantly with maturity of the plant. Although rust severity was generally delayed somewhat in upper leaves, it is believed that this may have been the result of environmental factors rather than resistance to the pathogen per se.

Keyword(s): American corn rust, corn.