Mz 4.1 U. maydis and S. reiliana2018-04-09T11:49:54-05:00

National Seed Health System

Mz 4.1  U. maydis and S. reiliana

DATE: 2001
PATHOGEN: Ustilago maydis/Sphacelotheca reiliana (syns: Ustilago zeae/Sporisorium holci-sorghi)
HOST: Maize (Zea mays)
COMMON NAME: common/head smut
METHOD: Mz 4.1 Washing test (McGee, 1988) (formerly Cf 4.1)
METHOD CLASS: Standard (A)
SAMPLE: : 400 seeds


1. Wash 400 seeds in sterile water for 15 minutes in a shaker.

2. Centrifuge at 3000 rpm for 15 minutes.

3. Remove the pellet and examine with a light microscope to confirm the identity of teliospores as described by Ainsworth (1965a) for U. maydis and Ainsworth (1965b) for S. reiliana


Ainsworth, G. C. (1965a) Ustilago maydis. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 79. Wallingford, UK: CAB International.

Ainsworth, G. C. (1965b) Sphacelotheca reiliana. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 73. International Mycological Institute: Kew, UK.

McGee, D.C., 1988. Maize diseases. A reference source for seed technologists. St. Paul, Minnesota, USA. APS Press. 149 pp.