Hello, everyone
Here is the second blight reminder for the year. Please
prepare accordingly for fungicide application for blight management this week,
and ensure you check with your processors on chemical requirements.
-
If you have fields in Cape Breton, Antigonish,
Pictou, and Guysborough, the crop stage (40% F2) is still early for Monilinia
Blight infection this week (May 4-10). I encourage you to utilize this week to
complete the sprout fields’ pre-emergence herbicide application.
-
If you have fields in Southshore counties
and Hants, your crop fields are in the susceptible period. Please monitor the
weather forecast and spray as needed.
-
In Cumberland, Colchester, and the
Musquodoboit Valley, some late fields, highland fields, or fields with late-development microclimates are still below 40% F2. Those fields will not have
the infection risk this week, but things can change quickly, so please monitor
your fields closely.
- *** Some fields in the above areas will enter potential infection periods this week. Therefore, I highly recommend producers in those areas check their crop field stage and apply fungicides as needed before the next wet and warm weather system impacts the province. The forecast is calling for a wet week after Tuesday. Those areas include Advocate, Parrsboro/Kirkhill, Halfway River/Newville, Oxford, Debert, Truro, and Dean.
The wet and warm weather of the last few days created
a suitable environment for mummy berries to germinate and produce cups with
ascospores. When there is a suitable infection environment (wetness and air
temperature, Figure 1), ascospores will infect open leaves and flower buds. The
following 2-3 weeks are critical for Monilinia Blight management in most production
regions.
Figure
1. Severity Rating of Monilinia Blight Infection Periods (Dr. Paul Hilderbrand,
AAFC)
A note about sprout fields: Plant emergence in
the central and northern regions is still early. After this point, it is
recommended that you find some calm days to spray the sprout fields.
Lastly, please check the latest wild blueberry weather
station GDD and crop stage (F2 %) updates below.
Wild Blueberry Weather Station GDD and Crop F2 stage updates
We selected the following 19 weather stations to
report their seasonal GDD accumulations. Please compare the cumulative GDD from
your weather station with local GDD recommendations on wild blueberry crop
stages: https://www.novascotiawildblueberryblog.com/p/phenology-tracker.html.
Figure 2. Selected Wild Blueberry Weather Stations and GDD Updates (April 1- May 4)
Table 1. Wild Blueberry Weather Stations and GDD
Updates (April 1- May 4)
The table below shows some available F2% information from
different regions.
Table 2. Percentage of Wild Blueberry Floral Bud F2
stage (Figure 3)
light green (0-20% F2), dark green (20-30% F2), yellow
(30-40% F2) and red (40-100% F2)
Wild blueberry production regions, NS |
The average percentage of fruit buds at F2 |
|
|
South West Nova Scotia |
|
West Caledonia |
>40% F2- May 4 |
East Kemptville |
>40% F2- May 4 |
|
|
Hants County |
|
Upper Rawdon |
|
|
|
Cumberland County |
|
Oxford |
= >40% F2- May 4 |
Springhill |
30% F2- April 30 |
Mapleton |
15% F2- April 30 |
Halfway River |
35% F2- April 30 |
Kirkhill |
30% F2- April 30 |
|
|
Colchester County |
|
Londonderry- Baseline Rd. |
20% F2- April 29 |
Westchester Mt. |
12% F2- April 29 |
Debert (WBPANS office) |
25% F2- April 29 |
East Mines |
20% F2- April 29 |
Murray Siding |
30% F2- April
28 |
Camden |
25% F2- April 28 |
Portapique |
25% F2- April 30 |
Montrose |
20% F2- April 30 |
|
|
Halifax Regional Municipality |
|
Musquodoboit Valley |
= < 40% F2- May 4 |
|
|
Guysborough County |
15-20%
F2- May 4 |
|
|
Pictou and Antigonish County |
|
New France |
20%
F2- May 2 |
Blue Mt. |
20%
F2- May 1 |
Millbrook and Lorne |
25% F2- May 1 |
|
|
Cape Breton |
<
20% F2- May 4 |
Figure 3. Wild Blueberry Floral Buds in F1 and F2 stages.