For over 30 years, the Phytopathology and Plant nutrition laboratory at Staphyt has been supporting its clients in selecting, testing, and evaluating their active substances and formulated products, both upstream and downstream of approval.
One of the laboratory’s flagship activities is the monitoring of pathogen sensitivities in crops to various active ingredients.
Detection of resistances
Fungicide resistance
The fight against fungal diseases in crops relies on various means, including the use of plant protection products. However, under certain conditions of use, phytopathogenic fungi can become resistant to these products. To prevent the emergence of these resistances and thus prolong the efficacy of fungicides in the fields, it is necessary to monitor the sensitivity of crop pathogens to the different active ingredients.
Following this surveillance, recommendations are issued to prioritize prevention and specifically manage resistance phenomena, as a prerequisite for maintaining long-term effectiveness. This surveillance is therefore part of the strategy for managing the fight against plant bio-aggressors in the context of plant protection product use compatible with sustainable development.
This surveillance is traditionally carried out using in vivo and in vitro tests, for which the Staphyt laboratory has over 30 years of expertise. Today, the system is complemented by molecular biology tools that allow both the detection and identification of mutations causing these resistances, as well as the quantification of these resistances.
For example, the laboratory has been monitoring the sensitivity of various pathogens to different active ingredients such as CAA, QOI, QoI, SdHI, etc., such as:
- Plasmorapa viticola,
- Erysiphe necator (downy mildew, powdery mildew of grapevine),
- Sclerotinia, Botrytis cinerea (gray mold),
- Phytophthora infestans (late blight of potato),
- Monilia (brown rot of fruits),
- Septoria tritici (septoria leaf blotch of wheat),
- Other pathogens are available on request.
Staphyt’s choice
Powerful sampling capability
The first step of monitoring involves collecting samples from the field. A sample consists of contaminated organs (for example, grapevine leaves showing symptoms of mildew) collected from a specific plot. This sampling must be done randomly and in sufficient numbers to be representative of the pathogen population in that geographical area.
Staphyt has an extensive network of stations and partners with trained technical teams for sample collection (Figure 1). Our clients can benefit from analyses carried out on samples from across Europe, giving them a complete and accurate understanding of the sensitivity of pathogen populations to their active ingredients.
