Practicing biological control using Coniothyrium minitans
1. Presentation
Characterization of the technique
Description of the technique:
Sclerotium of Sclerotinia sclerotiorum colonized by the bacterium Coniothyrium minitans
| Julien Halska | INRA | julien.halska(at)grignon.inra.fr | Dijon (21) |
Introduction into the plot of Coniothyrium minitans, a parasitic fungus of Sclerotinia sclerotiorum during an initial application, then maintenance applications on susceptible crops or on all crops in the rotation. The only commercial product containing this fungus is Contans WG®. According to Terres Inovia, the parasite can be applied in three ways:
- by spraying then incorporation by shallow tillage before sowing.
- after sowing, before heavy rainfall or irrigation (less effective technique).
- by spraying on infected crop residues.
Do not mix this product with chemical fungicides. The use of Contans WG® does not necessarily imply a fungicide break but reduces attacks.
Example of implementation: Spraying Contans WG® at 1.5 kg/ha, then incorporation with a rotary harrow and sowing of oilseed rape. Repeat the operation before sowing all susceptible crops in the rotation.
Implementation period On established crop
The parasitic fungus reduces the inoculum but does not eliminate it. Therefore, it is necessary to maintain the inoculum at a low level by maintenance applications following an initial application.
Spatial scale of implementation Plot
Since contaminations can come from outside the plot, it is also preferable to act on neighboring plots to reduce the inoculum.
Application of the technique to...
All crops: Not generalizable
Coniothyrium minitans is effective only against sclerotinia, so the technique concerns only crops susceptible to this pathogen. However, it is possible to apply it on other crops in the rotation to reduce inoculum.
All soil types: Easily generalizable
All climatic contexts: Easily generalizable
Regulation
POSITIVE influence
Contans WG®, based on Coniothyrium minitans, benefits from such authorization. Marketing Authorization
2. Services provided by the technique
3. Effects on the sustainability of the cropping system
"Environmental" criteria
Effect on air quality: Increasing
phytosanitary emissions: DECREASE
Effect on water quality: Increasing
pesticides: DECREASE
Effect on fossil resource consumption: Variable
fossil energy consumption: VARIABLE
Other: No effect (neutral)
If incorporation was not done during seedbed preparation, an additional sprayer pass is possible. Otherwise, incorporation does not require an additional pass.
Biodiversity : link=|alt=green face size 10
Contans WG® is very slightly toxic to fish and aquatic organisms. The product is free of toxicological and ecotoxicological classification. Replacing chemical treatments with this product is environmentally favorable.
"Agronomic" criteria
Productivity: No effect (neutral)
Yield losses due to sclerotinia vary depending on the species grown; biological control using Coniothyrium minitans helps limit losses to varying degrees.
Soil fertility: No effect (neutral)
Water stress: No effect (neutral)
Functional biodiversity: Increasing
Contans WG® is very slightly toxic to fish and aquatic organisms and is free of toxicological and ecotoxicological classification. Replacing chemical treatments with this product is favorable to the environment, notably to functional biodiversity (soil fungi).
"Economic" criteria
Operational costs: No effect (neutral)
Purchasing and spraying the product represent additional costs. Fungicides may still be necessary, so savings are not realized in the short term but after several years.
Mechanization costs: Variable
If incorporation was not done during seedbed preparation, an additional sprayer pass may be necessary.
Margin: No effect (neutral)
Fungicides may still be necessary, so savings are not realized in the short term but over the rotation.
"Social" criteria
Working time: Variable
If incorporation was not done during seedbed preparation, an additional sprayer pass may be necessary.
Effect on farmer health: Variable
Possible reduction in fungicide sprays, thus reducing risks for the user. Contans WG® is free of toxicological classification and is not subject to maximum residue limits, pre-harvest intervals, or risk phrases.
Observation time: No effect (neutral)
4. Organisms favored or disadvantaged
Favored Bioagressors
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Disadvantaged Bioagressors
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Favored Auxiliaries
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Disadvantaged Auxiliaries
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Favored climatic and physiological accidents
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Disadvantaged climatic and physiological accidents
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5. For further information
- Coniothyrium minitans, a biological control agent serving integrated protection
- -Annette PENAUD, Hervé MICHI
OCL journal, Peer-reviewed article, 2009
- Contans, something new. Recent results on this anti-sclerotinia fungus
- -oël Mathieu, Mathias von Erfa
Phytoma, no. 613, Press article, 2008
6. Keywords
Bioagressor control method: Biological control
Mode of action: Action on initial stock
Type of strategy regarding pesticide use: Substitution
