EPPO Global Database

EPPO Reporting Service no. 05 - 1996 Num. article: 1996/99

Puccinia horiana in North America

A NAPPO - Agriculture and Agri-Food Canada workshop on Puccinia horiana (EPPO A2 quarantine pest) took place in Ottawa, Ontario (CA), on 1994-09-15/16. This disease raises much concern in this region of the world as over the last years there have been several incidents reported from Canada, Mexico and USA.

  • Canada: P. horiana was observed in 1990 in one glasshouse in Ontario (Niagara Falls region) and was successfully eradicated. In 1993-94, the disease was reported from hobbyist gardens in British Columbia and an eradication programme was immediately set up.

  • Mexico: P. horiana was detected in 1993 in the State of Mexico and later in Distrito Federal and Morelos. The disease was eradicated from Distrito Federal and Morelos, but the eradication programme continued in 1994 in the State of Mexico.

  • USA: most of the incidents reported were in fact small and limited to private gardens, and the disease was successfully eradicated (e.g. in New Jersey, Oregon, Pennsylvania, and Washington). But in 1991, intrusion of P. horiana into commercial production was reported in California in Santa Barbara County. In 1992, it was reported from Santa Clara and Santa Cruz Counties. P. horiana was successfully eradicated from Southern California in 1993 but this is counterbalanced by repeated incidents in some commercial nurseries in Santa Clara valley and the threat of establishment in central coast areas. In California, P. horiana is submitted to an eradication programme. In its 1995 Annual Report, NAPPO mentions that approximately 750 chrysanthemum plants were found infected in an Oregon nursery, in September 1995 and two additional detections were made in Washington nurseries.


Chrysanthemum White Rust. Proceedings of the NAPPO - Agriculture and Agri-Food Canada Chrysanthemum White Rust Workshop. Ottawa, Ontario (CA), 1994-09-15/16.
NAPPO Bulletin no. 14, December 1995, 82 pp.

NAPPO Annual Report 1995, 40 pp.