Welcome to this weeks installment of the Vegetable Crop Report! As June comes to a close, we have seen a major increase in rain over the past week. Many counties have come much closer to their Ten Year Average, while others have overcome it!
Brassica Crops – Harvest continues for broccoli, cabbage, cauliflower and kale. Higher amounts of rainfall the past week will mean that conditions are more favourable for Alternaria. Reference the Ontario Crop Protection Hub to determine what products are registered for Alternaria depending on the specific Brassica crop that you are growing. Early detection and management of Alternaria will reduce potential inoculum later in the season. Alternaria resistance has been documented in other regions outside of Ontario and it is important to rotate FRAC groups after every Alternaria application. Dig stunted plants and observe roots for cabbage maggot larvae or pupae (Figure 1). Continue to scout for diamondback moth and imported cabbageworm eggs and larvae.
Garlic – Many areas have finished scaping and many fields are showing leaf tips starting to senesce. Tip dieback is likely due to stress which could be from late spring frosts, infrequent soil moisture, or root dieback caused by a pest or pathogen. Most fields with tip dieback were fairly dry in May despite the amount of precipitation we had in most areas in April. Continue to scout for leek moth damage. The frass and chewed pieces of leaf can look like sawdust on the leaves of garlic. The number of leek moth adults found in traps have increased over the past week and the second major flight will be over the next 3 weeks depending on the area. Dig up plants showing yellowing of the leaves from the bottom upwards and inspect the bulb and basal plate. Yellowing of the lower leaves is generally associated with stem and bulb nematode but it could also be Botrytis neck rot (Figures 2-3).
Peppers – Growers should be aware that in univoltine areas that peak flight of European corn borer (ECB) has begun. In overlap and bivoltine areas, peak flight of the first generation of ECB is also ongoing. Growers can use scouting and pheromone traps to help determine the presence of ECB in their crop, as there a very few pepper fruits currently on plants.
Tomatoes – Transplants are looking great and early plantings are starting to set fruit. With the recent storms, there is always a risk of disease coming in from the south and growers should be scouting for early symptoms of bacterial diseases. Grower should also be on the look out for symptoms of soil borne disease like fusarium, as the soils are moist. If you see unusual plant symptoms, like wilting, yellowing leaves, etc. and are concerns about fusarium, please reach out to Amanda Tracey at email@example.com.
Pest Degree Day Forecasting
|County||Carrot Rust Fly||Onion Maggot||Carrot Weevil||Aster Leafhopper||Tarnished Plant Bug||Cabbage Maggot||Seedcorn Maggot||European Corn Borer|
|THRESHOLD||329-395, 1399-1711||210-700, 1025-1515||138-156, 455+||128+||40+||314-398, 847-960, 1446-1604||200-350, 600-750, 1000-1150||See legend below|
*- Bivoltine region for ECB. First Peak Catch: 300-350 DD, Second Peak Catch 1050-1100 DD
**- Overlap region for ECB. First Peak Catch: 300-350 DD Second Peak Catch 650-700 DD, Third Peak Catch 1050-1100 DD
***-Univoltine region for ECB. Peak Catch 650-700 DD
Use these thresholds as a guide, always confirm insect activity with actual field scouting and trap counts.
Select a region below for the latest weather, crop and pest degree day information: