Project Overview

Reports

Commodities

• Agronomic: potatoes

• Ecosystem: other

• Human Health: workers, residents, applicators

Target Pests

Practices

• Pest Management: chemical control, genetic resistance, host resistance, pesticides

• Crop Production: crop improvement and selection, cropping systems

• Soil Management: soil quality/health

• Sustainable Communities: sustainability measures

Potato early dying (PED) remains one of the most persistent and economically damaging disease complexes affecting potato production in the North Central region. The disease is driven by the interaction of two soilborne fungal pathogens, Verticillium dahliae and Colletotrichum coccodes, which accelerate vine senescence, reduce canopy duration, and shorten the tuber bulking period. In the Red River Valley, decades of continuous or intensified potato production and limited rotation options have resulted in widespread and often high soil inoculum densities. Regional yield losses commonly reach 20–30 percent in infested fields, and growers consistently identify PED as a major constraint to both yield stability and processing quality. Soil fumigation remains the dominant management tool; however, growers report inconsistent performance, high application costs, and growing regulatory scrutiny. They also observe cultivar-dependent variability in PED expression and fumigation response, yet regionally validated, cultivar-specific guidance is lacking.

This project addresses these limitations using a field-based, on-farm research framework designed to quantify cultivar performance and fumigant efficacy under commercial production conditions. four widely grown processing russet cultivars—Russet Burbank, Hamlin Russet, Bannock Russet, and Dakota Russet—will be evaluated across multiple fumigant types and rates at sites with documented PED pressure. These cultivars span a range of known susceptibility to V. dahliae and C. coccodes, but they have not been systematically compared in side-by-side, replicated commercial field environments. Data collection will include assessments of vine senescence dynamics, canopy vigor, total and marketable yield, and tuber quality indicators relevant to the processing sector. Soil and plant tissue samples will be analyzed to quantify pathogen populations, enabling direct linkage between inoculum density, cultivar performance, and fumigant dose.

The project is organized around three objectives. First, we will characterize the response of each cultivar to PED under varying inoculum pressures in commercial fields. Second, we will determine how fumigant active ingredient and application rate influence disease suppression, yield response, and economic return across cultivars. Third, we will integrate disease, yield, and pathogen-quantification data to develop decision-support guidelines that assist growers in selecting appropriate cultivars and adjusting fumigation inputs based on site-specific disease risk. These guidelines will be refined with input from growers and processors to ensure they are agronomically realistic and operationally feasible.

The anticipated impact of this work is improved precision and sustainability in PED management across the North Central region. By identifying cultivars with greater tolerance to PED and quantifying conditions under which reduced fumigant rates maintain disease suppression and yield, this project has the potential to lower fumigant use, reduce production costs, and enhance economic resilience for regional growers. The outcomes directly support the mission of the North Central IPM Center by advancing integrated, data-driven approaches that reduce reliance on high-risk pesticides. Because the research is conducted through on-farm trials in collaboration with industry partners, the findings are positioned for rapid adoption. The project will also provide rigorous applied research experience for a graduate student, contributing to the region’s IPM workforce.

Objective 1: Determine how Verticillium dahliae and Colletotrichum coccodes contribute to early die development under commercial production conditions.

Objective 2: Discern the interaction between cultivar reaction and fumigation to maximize grower profits.

Objective 3: Develop grower recommendations on fumigation and cultivar selection based on soil pathogen infestations.