1st Monilinia Update for Nova Scotia 2018

Tuesday, April 24, 2018

It is has been a very strange winter and spring, with variable snow cover and warmer than normal temperatures through January and February. March and April have been quite cool, but in most areas the ground has been free of frost for some time.

Plant development is going to be very variable this year depending on snow cover, so it is very important to take a look at your fields to see how the fields are developing.

That being said we are starting to see buds swelling and some F2 buds are appearing.

I have a report from south west Nova Scotia - we are seeing buds swelling but very few floral buds at the F2 stage were noted.

I looked at an early field in the Debert area today, I noted that 5% of the Fruit buds were at the F2 stage.

If you have early fields and haven`t had snow cover for sometime, monitoring should begin this week.

Remember, it does not make sense to treat for Monilinia before 40% of the floral buds have reached the F2 stage.  After that point you only need to treat if there is an infection period. Infection periods are a combination of wetness duration and temperature.  The warmer the temperature, the shorter the wet period needs to be to cause an infection period.

Note:  All growers should check with their processors or buyers to see what products are allowable for their markets.  Propiconazole based products (Topas, Tilt, Jade, Bumper, Pivot etc.) have been a standard treatment for quite a long time.  There are some issues with continued mrls in Europe with this active ingredient, so some processors want to avoid using it this year as it could affect sales to Europe. Again check with your processor!!

There are other products available for use check, the update pest management guide http://www.perennia.ca/wp-content/uploads/2015/08/Wild-Blueberry-Pest-Guide-2018.pdf

Most of these products do need to be applied before an infection occurs.  Proline may have some post infection control but growers should be very cautious of pushing this back-action too far. As we move into May and there is a significant infection period forecasted and fruit bud development is well advanced, a pre-infection application might be well advised.

The second update will be late in the afternoon on Friday, April 27th.