PAPAS - Potatoes and Pests, Actionable Science Against Nematodes

Soil sampling bridges the gap between what growers can observe and what is actually happening in the ground. It’s especially important for identifying nematodes — above-ground symptoms often look similar to nutrient deficiency or drought stress.

A well-executed nematode soil sampling program should accomplish three things:
🪱 Identify the nematode species present
📊 Measure the population density of those species
📋 Interpret that data to predict potential crop damage and guide management decisions

The success of a sampling program's results depends on the quality of the samples collected. But determining the right number of samples to collect at the right depth, time, and location is not a one-size-fits-all approach.

In Build a Smarter Nematode Sampling Program for Better Management, PAPAS Project Co-Director and nematologist Dr. Inga Zasada explains how to design a sampling program that actually finds what's in the soil — and what to do with that information.
👉 PotatoNematodes.org/build-a-smarter-nematode-sampling-program-for-better-management

Twenty years of potato cyst nematode research — summarized in one essential article.

For the last two decades, the University of Idaho potato cyst nematode (PCN) program has led research and outreach efforts in developing strategies that support the regulatory goal to contain and eradicate the pale cyst nematode (Globodera pallida).

Louise-Marie Dandurand, Ph.D., Paige Hickman, Ph.D., and Lindsay Schulz have published a comprehensive overview of what that research has achieved in Potato Progress — and what it means for the future of nematode management in U.S. potato production:

🥔 Potato Cyst Nematodes: Foundational Research Driving Solutions for Potato Nematodes
🔗 potatonematodes.org/potato-cyst-nematodes-foundational-research-driving-solutions-potato-progress

Developing potato varieties with nematode resistance that also meet the needs of the market is a challenging undertaking and can take many years. Golden cyst nematode pathotype Ro1 is the success story.

Through the discovery of the H1 gene in the 1950s, many cultivars produced in the Northeast have introgressed Ro1 resistance into potato varieties, and it remains highly effective for controlling the golden cyst nematode in New York.

The majority of these cultivars align with the market needs of this region (round whites), enabling growers to reduce populations in their fields while producing a product they can sell. However, only two varieties carry resistance to pathotype Ro2, which is a growing concern.

See how the PAPAS project is working to ensure U.S. potato growers have resistant variety options for the full range of economically important nematode species across market classes: PotatoNematodes.org/closing-the-gap-in-nematode-resistant-potato-varieties.

We had a great time sharing the latest research in potato nematode management and connecting with industry experts at Potato Association of America . 🥔

Congratulations to graduate student Pia Spychalla on winning best presentation for “Identification of Candidate Genes for Ry-adg using RenSeq Tools.” Working in Dr. Walter De Jong’s lab at Cornell University, Pia researches potato genetics for breeding resistance to nematodes.

Learn more about the PAPAS project and its transdisciplinary team of researchers at PotatoNematodes.org.

By evaluating how Peruvian potato cyst nematode populations reproduce on standard potato varieties, we can better understand the vulnerability of current U.S. resistance programs.

This research directly informs Objective 2 of the PAPAS project: the development of durable nematode resistance in commercial U.S. potato varieties.

Read more about the research and what we’ve learned in "Virulence Diversity of Peruvian and United States Potato Cyst Nematode Populations Across a Panel of Potato Resistance Sources,” recently published in Plant Disease journal. 👇
PotatoNematodes.org/what-perus-pcn-populations-reveal-about-protecting-us-potatoes

The PAPAS team is heading to New Orleans for . On Monday, July 27, PAPAS researchers will present in the Potato Association of America symposium, Innovative Paths to Nematode Control, covering the latest science in potato cyst nematode management, resistance breeding, and the systems approach that makes durable control possible.

📅 Monday, July 27 | 1:00 p.m.
📍 New Orleans, Louisiana

Read more about the PAPAS team presentations: PotatoNematodes.org/innovative-paths-to-nematode-control-papas-at-paa-2026.

See how we’re making measurable strides in advancing nematode identification, decision support, and management methods — providing potato growers with more options to protect their crops.

🔗 Read the full article from Spudman Magazine: potatonematodes.org/papas-project-makes-strides-in-battle-against-nematodes.

French fries start with the right potato: processing-grade russets.

The growers who rely on these varieties are battling damaging nematode pests with limited tools — and no meaningful resistance.

Our team of researchers are working to change that, identifying new sources of resistance and incorporating them into commercially viable potato varieties, especially the russet market class.

Promising offspring that combine nematode resistance with strong agronomic performance are now in advanced field trials.

See how we're working to ensure potato growers have nematode-resistant varieties across market classes.
👉 potatonematodes.org/closing-the-gap-in-nematode-resistant-potato-varieties

A new study published in Plant Disease sheds light on the risk posed by the introduction of non-native potato cyst nematodes ( ; Globodera spp.) into U.S. production regions.

The PAPAS project and the University of Idaho PCN research team compared the virulence of Peruvian potato cyst nematodes to U.S. populations on standard differential lines, breeding clones, and commercial varieties.

The findings show Peruvian PCN populations exhibit substantially higher virulence diversity and complexity than U.S. populations — and current resistance sources may be vulnerable.

Read more about the research behind the study now available in Plant Disease, an international journal published by The American Phytopathological Society.

📄 PotatoNematodes.org/what-perus-pcn-populations-reveal-about-protecting-us-potatoes