By Lukie Pieterse, Potato News Today

Early multi-province research highlights nitrogen use efficiency as an emerging selection trait.

The Fruit and Vegetable Growers of Canada (FVGC) is spotlighting a potential shift in how potato varieties could be selected in the years ahead: not only for yield, quality, storability, and disease profile, but also for how efficiently they use nitrogen.

In a recent post on X, FVGC posed a pointed question – should growers eventually be choosing potato varieties based on how much nitrogen they need? The organization pointed to Cluster 4 research suggesting that newer potato cultivars may have superior nitrogen use efficiency compared to older varieties.

A related industry flyer authored by Dr. Mario Tenuta (University of Manitoba) provides a concise snapshot of early findings from multi-province field trials, and frames nitrogen use efficiency as an emerging trait that could matter more as sustainability expectations and input costs continue to shape decision-making.

What the September 2025 flyer reports – and what it does not

The flyer functions as an interim update rather than a full technical report. It summarizes direction-of-travel from ongoing trials without publishing full datasets, numeric performance tables, or detailed methodology in the public-facing document.

The update indicates that the project is in the second of three years of field trials, with research sites in Alberta, Manitoba, New Brunswick, and Prince Edward Island. Different nitrogen fertilizer rates were applied to standard table and processing varieties and to newer cultivars suspected to be more nitrogen use efficient.

The update reports that newer suspected high nitrogen-efficient varieties are generally out-yielding standard varieties, and that more yield is being achieved with less of an increase in nitrogen additions compared with the standard checks. Importantly, the flyer does not provide yield values, nitrogen rates, calculated nitrogen use efficiency metrics, or the statistical confidence behind these observations – suggesting the team is communicating early signals while broader analysis continues.

Why nitrogen-efficient genetics could become a mainstream selection trait

Nitrogen management in potatoes is rarely a simple “rate decision.” It influences yield potential, tuber size distribution, maturity, quality, and crop uniformity, while also shaping the risk of nitrogen losses to the environment. Potatoes can be especially sensitive to nitrogen timing and supply patterns, which is why small shifts in agronomy – or genetics – can produce outsized outcomes.

The larger message emerging from FVGC’s communication is that variety genetics may become a practical tool in nutrient strategy, not just an endpoint of breeding progress. If certain cultivars can maintain high yield with smaller increases in nitrogen application, the industry could gradually see more variety-specific nitrogen recommendations, rather than broad “one size fits most” assumptions.

Where 4R nutrient management fits into the story

Tenuta’s work sits within the 4R nutrient management concept – right source, right rate, right time, and right place. Traditionally, the 4R framework is applied as a management lens: optimizing fertilizer decisions to align agronomic performance with reduced losses.

What makes the Cluster 4 potato work notable is how it hints at a convergence between nutrient management and cultivar choice. In effect, a future “4R-aligned” nitrogen plan could involve matching both the agronomic approach and the genetic response profile of the variety, especially in processing systems where yield stability and quality thresholds are non-negotiable.

The eNtrench angle – emissions management meets field reality

The flyer also references the use of a nitrification inhibitor (eNtrench) and reports that it has generally reduced nitrous oxide (N2O) emissions across the trial program. However, it flags an exception in Alberta in 2024, where the field had significant residual nitrogen due to prior legume forage production.

This detail matters because it underscores a real-world truth growers already recognize: nitrogen outcomes are shaped by field history, rotation, residual fertility, and local conditions. Tools that reduce losses can still show variable responses depending on what the soil is already carrying and how the season behaves.

Musica – a useful reminder that high yield is not automatically high NUE

One of the more careful notes in the update involves Musica, a table potato variety described as drastically out-yielding checks. The flyer also notes that this higher yield came with more nitrogen added, and that researchers are working to confirm whether Musica is truly more nitrogen efficient.

This distinction is important. A cultivar can be high yielding because it responds strongly to higher nitrogen rates – without necessarily being more nitrogen efficient. True nitrogen use efficiency, in practical terms, tends to imply achieving more yield per unit of nitrogen applied, or maintaining yield while reducing the marginal nitrogen required for additional tonnes.

The fact that the flyer raises this question explicitly suggests the research team is separating “yield responsiveness” from “efficiency,” rather than assuming the two are the same.

What this could mean for Canadian potato growers

Even without published numeric data in the flyer, the implications are straightforward if these trends hold up through the third year of trials and broader validation:

• Variety selection may begin to include nitrogen response characteristics as a more formal trait, alongside yield, quality, storage performance, and disease package.
• Growers and agronomists could increasingly ask for nitrogen response curves by cultivar and by region – not just static rate recommendations.
• Newer cultivars suspected to be more nitrogen efficient could reduce the marginal nitrogen required to push yields, depending on soil type, field history, and market class.
• Emissions management tools such as nitrification inhibitors may remain part of the conversation, but will likely be judged by consistency across rotations and residual nitrogen scenarios.

What to watch next

For the research to become operationally useful at farm level, growers will be looking for decision-grade outputs beyond high-level statements. The next deliverables that would materially improve adoption include:

• Tables showing yield outcomes across nitrogen rates for standard versus newer cultivars, broken down by province and market class.
• Clear definitions of how nitrogen use efficiency is being calculated in the project, including whether quality thresholds are incorporated.
• Further clarification on Musica – whether it demonstrates true efficiency, or whether it is primarily a high-response variety that performs best with higher nitrogen.
• Ongoing reporting on how nitrification inhibitors perform under varying residual nitrogen conditions and rotations.

FVGC’s framing is ultimately about preparing the industry for a plausible near-future shift: cultivar choice and nitrogen strategy may become more tightly linked, as genetics and nutrient stewardship expectations evolve together.

Author: Lukie Pieterse, Potato News Today
Cover image: Credit Katuschka from Pixabay