16 Jul Agronomy Update – July 16th

Hi everyone,

Sorry that this week’s update is a little bit late…I’m taking in the Potato Sustainability Alliance Symposium in Charlottetown today and tomorrow.

Yesterday, I was able to get out into several fields in East Prince, as we also had the 2^nd Crop Update Meeting of the summer in Kensington in the afternoon.  I’m starting to see a little bit of early blight/brown spot showing up in fields, but incidence is relatively low.  Few other foliar disease symptoms have been observed.

The lack of rainfall in the last 7-10 days is starting to have an impact on the crop.  Soil moisture levels are below wilting point in many fields. Some early planted fields are already starting to lay down a bit in the canopy with senescence of bottom leaves. Many fields planted in late May are flowering but haven’t achieved full canopy due to the lack of moisture. Hopefully some well timed rain in the near future will help most fields “close the rows.”

I’m getting several calls about spraying for early blight and brown spot. Here is a list of chemistries that are labelled for both early blight and brown spot control:

• Luna Tranquility (Group 7 & 9)
• Miravis Duo (Group 3 and 7)
• Cevya (Group 3)
• Quadris Top (Group 3 & 11)
• Veltyma (Group 3 and 11)
• Aprovia Top (Group 3 and 7)

Growers are advised not to spray the same chemistry back-to-back. For example, is spraying Luna Tranquility (Group 7 & 9) first, the next spray should be with products that are Groups 3 or 11 (or both), ideally.  Rotating chemistry and avoiding over-use of chemistry will help us keep effective products longer.

Air Spore Report:

• All sites are now reporting.
• No late blight spores in PEI or NB.  Maine continues to report LB spores but no foliar disease.  No late blight has been reported in ON or QC this season.
• Early blight numbers spike high in East Prince and Kings last Friday and Monday before declining today.  Brown spot numbers have also declined.
• Alternaria often thrives in hot, humid weather. Grey mold spores are very low, reflecting the weather.

Aphid Alert: 

• Full regional details are below.
• After averaging over 5 aphids per sample last week, numbers counted so far from this week are generally lower (2.2 aphids/trap); however, no samples from East Prince have been counted yet, and this has the be highest region in recent weeks.
• The majority of aphids continue to be non-colonizing aphids. No green peach aphids were found last week or so far this week.
• Seed growers should continue to be diligent with oil applications and aphicide applications as needed.

Additional Pest/Disease Notes: 

• European corn borer egg masses are being detected across the province, with many at blackhead stage or emerging.  Incidence is not uniform across the province or within regions.
• Colorado potato beetles are widespread, but damage is variable by field/region. In many fields, CPB are still being controlled by in-furrow neonic chemistry. There are a few reports of fields with higher levels of damage.
• Scattered reports of thrips and leafhoppers. This may be more acute in hot, dry weather. Also some reports of tarnished plant bugs but not at threshold levels.
• Volunteer potatoes are very prevalent this year, especially close to woods/hedgerows. Growers should be paying attention to last year’s potato fields and scouting for volunteers, especially those not chewed down by potato beetles. There is a new factsheet on volunteer management on the Agronomy Site.
• I’m getting very few reports of foliar disease, but that may change as the plants are stressed by lack of moisture.

Weather Station Data:

 The PEI Agri-Watershed Partnership, in collaboration with UPEI and myself, are in the process of getting several of the UPEI weather stations back up and running this growing season.  Some must be repaired after not being serviced for a couple of years, and some work needs to be done to get them all reporting on the PEI Climate App that was designed a few years ago.  In the meantime, individual stations can be accessed on the Agronomy Site under the Weather tab on the header bar. There are also links to the PEI Department of Agriculture stations as well as the COCORAHS network.

Please have patience as we get the UPEI stations back up and running. I hope that we’ll have a better platform to share weather station data by the fall, and then we also hope to build some additional tools for producers using this data.

UPEI Sustainable Ag Conference:

UPEI is hosting a Sustainable Agriculture Conference on August 5^th and 6^th in Charlottetown. More on this event is available at https://atlanticsustainableag.ca/. Registration is now open, with a fee of $125.

2025 AAFC Harrington Stakeholder Day

Date: Wednesday, July 30th (Rain Date Thursday, July 31st)

Time: 10:00am to 3:00pm

Location: Harrington Research Farm, 1200 Brackley Point Road, Harrington, PE C1E 1P9

Please sign up with this link https://www.signupgenius.com/go/60B094EA8AE29A2FB6-57336747-2025 or email charlotte.thompson@agr.gc.ca