Pale Cyst Nematode Five Year Review Report

Idaho Falls, Idaho – March 2012

PCN 5 Year Review Report

Idaho Falls, Idaho – March 2012

Following the detection of pale cyst nematode (PCN) in Idaho in 2006, the United States 

Department of Agriculture’s Animal and Plant Health Inspection Service’s Plant Protection and 

Quarantine program (USDA APHIS PPQ) and the Idaho State Department of Agriculture 

(ISDA) established an eradication plan in early 2007 with input from an international panel of 

scientific and technical experts. The plan included a review to evaluate the efficacy of the 

program and its eradication efforts after five years of treatments.

In March 2012, officials from PPQ, ISDA, and the Idaho Potato Commission met to conduct the 

five year review of the program. The review included one day of meetings with stakeholders in 

which seven industry representatives expressed the views of growers with infested, regulated, 

and deregulated fields; shippers; growers with fields outside the regulated area; and exporters.

This was followed by two days of discussion and analysis of the latest program information and 

input from technical experts with resultant adjustments made in program procedures and policy.

The key findings and results of the five year review include the following:

We agreed that the original goals of the program, listed below, are still valid, and that 

significant progress has been made toward meeting these goals. Eradication will remain 

the program’s focus in 2012 and beyond.

o Prevent the spread of PCN

o Delimit the current infestation

o Eradicate the current infestation

o Restore lost foreign markets

o Preserve current markets

The program has been able to establish procedures for detection and treatment that were 

unknown prior to the discovery of PCN in Idaho. Standards for detection, identification, 

treatment, and field and equipment sanitation have been refined through the joint efforts 

of growers, processors, shippers and agriculture officials.

Since 2006, potato field surveys in 26 other states have not detected PCN. The Idaho 

infestation is limited to less than 1,800 acres*, all within a 5-mile radius in two counties. 

Over 300,000 samples* throughout Idaho have been collected and analyzed to delimit the 

infestation.
Pale Cyst Nematode Five Year Review Report

Idaho Falls, Idaho – March 2012

Nine infested fields found in the first three years have had treatments, which have 

reduced cyst populations to less than 1% viability. Five of those fields are in greenhouse 

bioassay at the University of Idaho in Moscow, the final step before again allowing a host 

crop to be planted. Sampling will be conducted after each of the next four host crop

plantings. 

Trade with all of our trading partners (including those that originally barred import of 

Idaho potatoes) has been restored except for Japan. We continue to work with Japan to 

recover that market. However, other export markets have been expanded.

Costs have been reduced and the program is making effective use of available resources. 

Funding has averaged approximately $7 million per year since program inception with 

$5.5 million allocated in fiscal year 2012.

Some other adjustments to program procedures and policies that were adopted during the review

include the following: 

Formalize and implement an Owner/Grower communication plan to keep stakeholders 

engaged and working with the program. 

Modify criteria for the release of newly regulated fields by not releasing fields until we 

have negative results following four 2000cc (20 pound)/acre soil samples taken by 

APHIS after each of two potato crops.

Continued ISDA involvement for intrastate movement violations and authority to sample 

in instances where APHIS is denied access to a field.

Evaluate two biocontrol agents and rapeseed meal as a biofumigant to supplement 

chemical eradication.

Continue to deprive PCN of hosts in all fields and propose that all fields receive a 

minimum of two methyl bromide treatments.

Convene a meeting of the review stakeholder group to talk about the review and discuss 

proposed changes. 

*Please see the program website for the current statistics: 

http://www.aphis.usda.gov/plant_health/plant_pest_info/potato/pcn.shtml