Some Viewpoints on the Phylogeny of Rust Fungi. IV. Stem Rust Genealogy

Abstract

Since the discovery and first description of the black stem rust, Puccinia graminis, by Persoon (1794, 1801), more attention has been devoted to this species than to any other rust on cultivated plants. This is due partly to the great losses caused by stem rust in all grain-growing countries, and partly to the persistent interest of uredinologists in the life history of the heteroecious rusts. Recent investigations of heterothallism, physiologic races and hybridization among stem rust strains have contributed much to our knowledge about the genetic constitution and mechanism of inheritance of rust fungi. This in turn has rendered valuable service to plant breeders in their search for rust-resistant crop varieties.