Development of an Infection Assay for Sporisorium reilianum, the Head Smut Pathogen on Sorghum

摘要: The practical value of dry teliospores Sporisorium reilianum as inoculum in head smut infection assays was determined from a series studies using three different isolates the pathogen. Overall germinability ranged 8.0 to 28.0% on culture media after 48 h incubation. Teliospores germinated at slower rates vicinity sorghum seedlings growing germination paper, reaching maximum values 11.5 13.0% 120 h. These results suggest adaptation strategy S. reilianum, probably modulated by variable soil environment. Fifteen percent (15%) susceptible maize hybrid inoculated with root protrusion openings mesocotyl tissues became infected, while similarly sporidial suspensions remained uninfected. Three lines were separate experiments Corpus Christi and Taylor, Texas. Seeds imbibed for 18 h, planted 40% moisture content (wt/wt) covered 1:50 (vol/vol) mixture autoclaved soil. Infection levels obtained these 2.5 2.8 times higher than field RT×7078 B1. In this study, average 65 79.5% 84 87% B1, respectively, reilianum; whereas Taylor infected 91.9 82.3% plants two lines. It is postulated that increased efficiency observed inoculation technique uniform inoculum, timely delivered under stable conditions provide pathogen an environment more conducive infection.