Previous work in this laboratory (20) showed that germ tubes of Puccinia coronata uredospores would form structures in vitro resembling those found in infected host plants (18). This so-called vesicle formation occurred on Difco gelatin in the pH range of 6.2 to 6.9 on addition of 14 to 22 X 10-5 M Zn. Under these conditions germ tube length was reduced, and in some cases the percentage germina...

ABSTRACT: The evolution in virulence of Puccinia coronata f. sp. avenae has challenged the genetic resistance to crown rust oat genotypes. New sources are constantly required for yield stabilization and costs reduction. This study aimed characterize genotypes disease´s productive economic impact. Experiments were conducted two environments, with without chemical control. Resistance was measured...

ABSTRACT Crown rust, caused by Puccinia coronata var. hordei, is a new disease threat to barley in the Great Plains region of the United States. Deployment of resistant cultivars is the only economically viable option for the control of this disease. Thus, the objective of this study was to investigate the sources and genetics of crown rust resistance in barley. A geographically diverse sample ...