Tavelure du pommier:direct combat using decision support systems
There are field hygiene measures and tolerant varieties against scab of apple (Venturia inaequalis). To prevent resistance from being overcome, direct control with plant protection products remains the most effective measure in organic production.
Solution
Based on the biology of the pathogen and local weather forecasts, decision support systems, for example RIMpro or Simscab, allow farmers to assess the risk of infection by apple scab and to choose the optimal timing to take direct protection measures for the crops.
Advantages
Decision support systems such as RIMpro provide forecasts on infection events and help farmers make decisions for more effective treatments and better control of scab.
Practical recommendation
| Stage | Bud break (BBCH 53 (C)) to balloon stage (BBCH 59 (E2)) File:Apple scab- direct control using decision support systems 3.jpg |
Balloon stage (BBCH 59 (E2)) to end of flowering (BBCH 69 (H))[1] File:Apple scab- direct control using decision support systems 2.jpg |
End of flowering (BBCH 69 (H)) to stage T (BBCH 74)[1] File:Apple scab- direct control using decision support systems 1.jpg |
Stage T (BBCH 74) until harvest |
|---|---|---|---|---|
| Preventive treatment | Copper[1] (300 to 150 g pure copper/ha[2][3])
and/or |
wettable sulfur[2] (6-8 kg/ha[3]) (+sulfur clay[4] (8 kg/ha[3]))
or sulfur lime (10-16 l/ha[3]) |
wettable sulfur[2] (2-4 kg/ha[3])
(+ sulfur clay[4] (8 kg/ha)) or sulfur lime (8-12 l/ha) |
wettable sulfur (2-4 kg/ha) (+ sulfur clay (8 kg/ha))
or wettable sulfur (2-4 kg/ha) + copper (100-150 g) |
| Stop treatment | sulfur lime[5] (10-16 l/ha[3])
or potassium bicarbonate (4-5 kg/ha[3]) |
sulfur lime (8-12 l/ha[3])
or potassium bicarbonate (4-5 kg/ha[3]) | ||
An adhesive and/or wetting agent can be added to improve efficacy.
- ↑ 1.0 1.1 1.2 Copper: Reduce the amount as flowering approaches, and do not use copper from flowering to stage T (risk of russeting).
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Sulfur: Use if T >12 °C (no effect below this temperature as sulfur acts during evaporation). The higher the temperature, the lower the dosage should be.
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 Dosage for 10,000 m3 foliage volume or 2 meters canopy height. Check specifications and country authorization.
- France : Pesticide index.
- Germany, Switzerland, Austria : FiBL input list.
- Italy : Italian input list.
- ↑ 4.0 4.1 Sulfur clay: Add sulfur clay for additional effect against apple leaf fall disease (Marssonina coronaria); sulfur clay is currently authorized in Italy and Switzerland.
- ↑ Sulfur lime: Caution, during flowering phase, sulfur lime has a thinning effect at high dosage.
Applicability box
- Topics: Crop production, horticulture.
- Application time: March/April until harvest.
- Time required: Check the RIM-pro forecast model regularly when rain events are forecast.
- Equipment: Smartphone or computer with internet access. Weather station near the orchard and user access to the RIMpro platform.
- Preventive treatment before the infection period: freshly germinated ascospores are very sensitive to contact fungicides, so a preventive treatment can be applied before spore release (Fig. 1, A).
- Stop treatment on wet foliage: the amount of germinating ascospores over time is indicated by the white area behind the yellow bar (Fig. 1, 7). During this time, a stop treatment will kill the spores (Fig. 1, B).
External links
- FiBL input list for organic farming
- Visit the organic farming knowledge platform for more practical recommendations.
- Forecast model for apple scab RIMpro
- Article in Bioactualités magazine on the apple apple scab forecast model RIMpro
- Other apple apple scab forecast models: Fruitweb, Farm Software, Simscab, Metos
- Technical sheet on plant protection for organic pome fruit production in the FiBL shop
Sources
La version initiale de cet article a été rédigée par Clémence Boutry, Mathias Ludwig et Hans-Jakob Schärer.
Original source: BioFruitNet 2022 - https://organic-farmknowledge.org/tool/44111
