Pest/Disease Update – Aug 1

Quick pest/disease update for the end of the week:

 

July Weather Report:

 

Table 1: Rainfall amounts for the month of July (current year 2025 vs historical records 1981-2010)

Rainfall (mm)
Location July 2025 Historical
1981-2010
Difference
O’Leary 98.0 96.0 2.0
Summerside 40.7 82.1 -41.4
Charlottetown 44.8 79.9 -35.1
Souris 63.0 86.6 -23.6

 

Table 2: Cumulative rainfall totals for 2025 growing season compared with historical cumulative rainfall

Rainfall (mm)
Location May 2025 June 2025 July 2025 2025

Cumulative

Historical Cumulative Difference
O’Leary 89.4 70.0 98.0 266.4 283.7 -17.3
Summerside 89.3 49.8 40.7 179.8 272.1 -92.3
Charlottetown 99.1 102.1 44.8 246 269.7 -23.7
Souris 84.4 97.6 63.0 245 280.6 -35.6

 

Only West Prince had average rainfall in July, with East Prince and Charlottetown being about 50% of normal.  So far this growing season, Summerside has only had 66% of normal rainfall, while other locations are at 85-90% of normal rainfall.

Growing degree days (GDD) were about 10% above normal in July across the province, and are about 10-15% above normal for the season so far.

 

Aphid Alert:

  • Total aphids down slightly this week (3.1 per sample vs 4.1 last week)
  • Majority of aphids continue to be “other aphids”, but we did trap one Green Peach Aphid this week
  • Tarnished plant bug numbers are increasing, though not at threshold levels in most fields.
  • East Prince continues to have the highest amount of aphids.

 

Region Week Ending Number of Samples Green Peach Aphid Potato Aphid Buckthorn Aphid Bird Cherry-Oat Aphid Other Aphid Tarnished Plant Bug Total Aphids Ave. Aphids per Sample
WEST PRINCE 02-Aug-25 28 1 9 5 1 53 6 69 2.46
EAST PRINCE 02-Aug-25 28 0 3 9 7 129 21 148 5.29
CENTRAL QUEENS 02-Aug-25 22 0 1 3 2 33 4 39 1.77
SE QUEENS/KINGS 02-Aug-25 2 0 0 0 1 4 0 5 2.50
EAST KINGS 02-Aug-25 14 0 6 2 0 23 3 31 2.21
  Total 94 1 19 19 11 242 34 292 3.11

 

Air Spore:

 

July 30th, 2025
Early Blight Brown Spot Grey Mold  
West Prince 0 11 4  
East Prince 27 42 5  
Queens 0 3 2  
Kings 8 0 1  

 

  • No late blight spores detected in PEI or NB so far this week. The weather does not look favourable to late blight development for the next week.
  • Early blight and brown spot spore counts are starting to increase in East Prince, where it has been driest.
  • Bortrytis spores remain low and risk of infection remains low.

 

Additional Notes:

 

  • There is a demo of a 360 Rain irrigation system taking place next Tuesday and Wednesday (Aug 5/6) in Emerald. If interested in checking this out, please contact 46Ag at (902) 874-0348 or emily@46ag.ca.
  • The next Crop Update meeting will be held Aug 12th at AIC in Kensington at 2:30 pm. Zoom details will be circulated ahead of the meeting.