PEST MANAGEMENT DECISION GUIDE: GREEN AND YELLOW LIST
Powdery Mildew on Strawberry
Podosphaera macularis f. sp. Fragariae (Podosphaera aphanis) Powdery mildew disease
- Plant resistant varieties such as pajero, douglas from Simlaws and Kenya Seed Company.
- Plant in soils with good drainage
- Space the plants with 3-4 feet between rows to increase aeration within the crop
- Practice crop rotation with non-host crops, such as maize or sorghum, for at least 2 years.
- Prune the affected leafy vegetation and weed regularly to remove host plants within the farm.
- Look for purple reddish blotches on the upper and lower surface of leaves
- Look for young small leaves with white to grey powdery deposits on the undersides, causing leaf roll up
- Look for immature hard and deformed fruits
- Look for infected mature fruits with white powdery deposits
- Take action when 2 to 3 leaves have grey to white powdery growth on one plant
- Uproot and burn infected plants in the field to reduce the spread of disease to healthy plants
- Avoid overhead irrigation to reduce spread of the disease
- Clean your tools thoroughly with Jik solution (3 to 5 ml in 1 litre of water) before using them on clean plants
- Water early in the morning or after sunset, and try to keep the water on the soil, not the leaves
- Spray the plants by using Trianum-P (Trichoderma harzianum) at a rate of 15g in 5L or Trichotech (Trichoderma asperellum) at a rate of 2.5g in 20L of water
- When using a pesticide, always wear protective clothing and follow the instructions on the product label
- Do not use chemicals with the same mode of action year after year as this can lead to resistance
- Always consult the most recent list of registered pesticides (PCPB)
Spray Azoxystrobin 250 g/L, such as Ortiva® 250 SC. Apply 20ml in 20L of water. Apply at 0.5L/ha
WHO Class III (Slightly hazardous). REI: 12hrs. PHI: 5days. Apply twice at 7-14 day interval.
Spray mancozeb 80WP 640g/L, appropriately diluted, and repeat at an interval of 7 to 10 days.
WHO class U. REI 4 hours. PHI 7 days
CREATED/UPDATED: Dec 2018
PRODUCED BY: Plantwise
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