PataFEST publishes two studies on biocontrol against potato diseases

PataFEST researchers have published two papers in Acta Horticulturae (2026), the journal of the International Society for Horticultural Science (ISHS). Both explore biocontrol solutions to manage two potato diseases caused by soil-borne pathogens: black dot and Fusarium dry rot.

Biocontrol coating and controlled atmosphere to manage potato black dot during cold storage

As the authors point out, the quality of potatoes for the fresh and pre-packed market depends mainly on their appearance, which determines whether consumers accept or reject them. Black dot, caused by the fungus Colletotrichum coccodes, produces silvery-brown lesions on the skin. According to the paper, these lesions spoil the tuber's appearance and reduce its marketability.

The researchers note that little work has looked at controlled atmosphere (CA) for sprout control in potato storage, and that no previous studies had addressed its impact on black dot. Their study therefore examines the effect of CA, a biocontrol coating and the interaction between the two on black dot development during cold storage, as well as their effect on tuber quality:

• Storage atmosphere: tubers were stored either under continuous air flow or under CA (3% CO₂ and 5% O₂).
• Biocontrol coating: half of the tubers were kept as a control; the other half were treated with an edible coating combined with a biocontrol agent based on the action of enzymes.

The team stored 'Maris Piper' tubers for 4 months at 3 °C and over 90% relative humidity. Each month, they visually assessed black dot severity (% of tuber surface affected) and measured respiration rate, weight loss, dry matter, firmness and individual sugars.

The authors frame their results within a broader initiative to develop a holistic integrated pest management strategy. In their words, the ultimate goal is to reduce food loss and waste in the UK potato supply chain.

Authors: M. Sanzo-Miró, C. Ghidelli, B. Pérez Bibbins and M.C. Alamar. Presented at the XIV International Controlled and Modified Atmosphere Research Conference. Read the paper.

Wickerhamomyces anomalus as a biocontrol agent against Fusarium sambucinum

According to the paper, dry rot caused by Fusarium sambucinum occurs both in the field and in storage, causing major economic losses for potato growers and the pre-packed potato industry. Standard chemical pesticides are used to control it, but the authors warn that their overuse can increase pesticide resistance in soil-borne pathogens.

The researchers see biocontrol agents as a promising biotechnological tool to meet the demand for more environmentally friendly, chemical-free alternatives. In this study, they investigated the antifungal activity of Wickerhamomyces anomalus, a "killer" yeast that produces the enzyme β-1,3-glucanase. As the paper explains, this enzyme breaks down the β-1,3-glucan chains in the cell walls of pathogenic fungi.

To improve the antifungal activity and biomass production of W. anomalus, the team studied several parameters: glucose concentration, different β-1,3-glucan inducers (corn starch, barley and yeast glucan), C:N ratio and liquid:void space ratio. The paper reports the following main results:

• Highest total protein concentration: a C:N ratio of 1:2 (using 20 g/L glucose and 30 g/L corn starch as carbon source) and a liquid:void space ratio of 1:4.
• 50% reduction of F. sambucinum on potato tubers in in vivo tests: yeast produced at 48 h with 30 g/L barley glucan and 20 g/L glucose, a C:N ratio of 1:2 and a liquid:void space ratio of 1:19.

The authors describe these as preliminary results, part of a broader research initiative on sustainable integrated pest management strategies for the potato supply sector.

Authors: B. Pérez Bibbins and C. Ghidelli. Presented at the International Symposium on Biotechnological Tools in Horticulture. Read the paper.

Towards integrated pest management for potatoes

Dry rot, black dot and silver scurf are the main postharvest diseases of potato. They are caused by soil-borne pathogens that affect the crop both in the field and in storage.

Both studies are part of a broader effort to develop integrated pest management (IPM) strategies for the potato supply chain. One of PataFEST's aims is to develop postharvest technologies (biocontrol coating, controlled atmosphere storage and volatile organic compound (VOC) sensors) to control soil pathogens and maintain the quality of stored tubers.

References

1. Sanzo-Miró, M., Ghidelli, C., Pérez Bibbins, B. and Alamar, M.C. (2026). Biocontrol coating and controlled atmosphere as innovative postharvest solutions to manage potato black dot during cold storage. Acta Horticulturae 1456, 293–300. https://doi.org/10.17660/ActaHortic.2026.1456.38
2. Pérez Bibbins, B. and Ghidelli, C. (2026). Use of Wickerhamomyces anomalus as a biocontrol agent against soil-borne pathogen Fusarium sambucinum. Acta Horticulturae 1454, 223–230. https://doi.org/10.17660/ActaHortic.2026.1454.31