Location: Emerging Pests and Pathogens Research
Project Number: 8062-21000-048-008-I
Project Type: Interagency Reimbursable Agreement
Start Date: Jul 1, 2022
End Date: Sep 30, 2023
Objective:
The goal of this project is to replace the post-harvest grow-out test used in seed potato certification with commercial scale high throughput laboratory testing. This will provide the seed potato industry with swifter and more accurate seed health data and the ability to respond to emerging diseases, both of which are required to maintain a healthy seed potato supply.
To meet this goal, the three project objectives are:
1) Develop a workflow for commercial high throughput PCR testing of seed potatoes.
2) Establish a model for the adoption of PCR-based seed potato testing by the potato industry.
3) Identify and mitigate barriers for wide scale adoption related to farm level tuber sampling and PCR-based seed potato testing approach.
Approach:
The design of this project is based on the premise that high throughput laboratory based detection of viruses from tubers directly would facilitate more accurate and faster delivery of results to seed potato growers than conventional approaches followed by state seed potato certification agencies. Two long-term goals of this project are: Improved decision-making support for seed potato certification so the potato industry can respond quickly to emerging pathogens and reduce spread of tuber-borne viruses and generate awareness towards harmonization of seed potato certification rules across all potato producing states in the US.
We will use FTA cards on a larger scale eliminating the need for transporting tubers that are bulky and covered in dirt. We will use well-validated PCR assays from peer-review publications. Whatman FTA Plantsaver® Cards will be procured to enable sampling of ~200 seed lots. We will provide the partnering commercial laboratory with FTA cards, positive, negative controls, and tuber samples so they can develop an in-house protocols and workflow that would facilitate high throughput processing of samples. The company also implements barcoding throughout the laboratory workflow tracking samples at the case, item, tube, and plate level. This approach will help reduce errors when actual samples are received by the laboratory. The contract laboratory will develop a workflow that is transferable and provide capacity building strategies that could be utilized by regional or state labs for seed potato certification.
We will ask our grower cooperators to provide their farm crew to sample tuber cores on FTA cards. The field crew will be trained on-site by participating seed certification inspectors and researchers. Through this project, we will evaluate approximately 200 seed lots. Tuber cores from 25 tubers will be placed on one FTA card and pressed using hydraulic press. The potato solids will be removed, cards dried and then shipped to commercial lab for further processing. We will generate instructional videos and extension materials for sampling and submitting FTA cards to the partner commercial laboratory. Specifically, this How-To guide will provide information regarding a list of materials needed for sampling, common errors to avoid.
We will obtain information from our grower cooperators about seed lot results, existing seed certification summer results, vine kill dates, and aphid numbers to seek out additional uses of early and accurate information about PVY and field status of PMTV and TRV.
To help reach our goal of identifying and identifying and mitigating barriers for wide scale adoption related to farm level tuber sampling and PCR-based seed potato testing approach, we will develop a questionnaire asking each cooperator to respond regarding pros and cons for on-farm sampling, interpreting, and accepting results from a commercial lab and how they compare with state seed potato certification agencies. In addition, we will conduct at least one brainstorming session each year for the cooperators to air their concerns and identify measures to overcome these bottlenecks.