Influence of Media on Pathogenicity and Morphology of Secondary Sporidia of Tilletia indica. E. J. Warham, CIMMYT, Apdo. Postal 6-641, Mexico 06600 D.F., Mexico. P. A. Burnett, CIMMYT, Apdo. Postal 6-641, Mexico 06600 D.F., Mexico. Plant Dis. 74:525-527. Accepted for publication 10 September 1989. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0525.

Sporidia of Tilletia indica were produced in potato-dextrose broth with or without supplemental sucrose after 1 wk on a shaker. Secondary sporidia produced in liquid cultures were characteristically filiform and distinguishable from allantoid secondary sporidia produced on potato-dextrose agar plates. Boot and spray inoculations of bread wheat with filiform secondary sporidia resulted in lower levels of infection than similar inoculations with allantoid secondary sporidia. When screening germ plasm for Karnal bunt resistance, allantoid secondary sporidia produced in solid media should be used as inoculum.