Differential Sporulation of Pathotypes of Peronosclerospora sorghi on Inoculated Sorghum. Jeweus Craig, Research Plant Pathologist, Agricultural Research Service, U.S. Department of Agriculture, Plant Sciences Department, Texas A&M University, College Station 77843. R. A. Frederiksen, Professor, Plant Sciences Department, Texas A&M University, College Station 77843. Plant Dis. 67:278-279. Accepted for publication 28 July 1982. 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, 1983. DOI: 10.1094/PD-67-278.

A system was devised for differentiating pathotypes of Peronosclerospora sorghi according to their ability to sporulate on inoculated leaves of differential sorghum (Sorghum bicolor) genotypes. In 1980, a new pathotype (pathotype 3) was discovered in Texas among populations of P. sorghi that sporulates on lines Tx412, Tx430, and CS3541 but not on QL3.

Keyword(s): sorghum downy mildew.