The Animal and Plant Health Inspection Service (APHIS) of the United States Department of Agriculture (USDA) has published a notice and comment request for stakeholders to provide their thoughts and concerns regarding potential changes to the federal regulatory program for the non-native fungal pathogen Chrysanthemum White Rust (CWR; Puccinia horiana
). The disease is currently treated as a regulated and quarantine pest. This allows federal officials to restrict where chrysanthemum cut flowers and cuttings can be imported from, reject shipments if the disease is detected at U.S. ports of entry, and pursue eradication measures if it is found domestically. However, CWR has shown itself to be difficult to manage with localized outbreaks occurring since the late 1970s in various parts of the U.S. Following the comment period (closes on Oct. 2nd) APHIS will choose one of the four following options:
- Maintain the current status of CWR as a regulated and quarantine pest.
- Change the status to a regulated non-quarantine pest. This approach would support the creation of a certification program to reduce the risk of producers and distributors from spreading CWR but would prevent federal officials from responding to domestic outbreaks.
- Largely de-regulate the disease, no longer preventing its importation on chrysanthemum plants or pursuing eradication measures. However, states that have shown that they are CWR free and develop an official control plan can request that APHIS continue to regulate the disease at U.S. ports of entry if the state listed as the final destination of the shipment.
- Completely de-regulate the pest, committing to no federal action and allowing propagators, growers, and distributors to treat it as a quality pest.
CWR was known only from Japan and China until the 1960s when it was believed to have spread to South Africa and Europe, and eventually made its way to South America and the United States. The disease primarily infects the leaves but can also be found on stems and flowers under severe infections. Sunken pustules develop on infected leaves which can eventually wilt and dry. CWR spreads predominately by rain splash but spores can travel upwards of 700 meters under extremely high humidity conditions (90% or greater relative humidity) and strong winds.
To view the notice and instructions for comment, click here