Mummy Berry 2019 #9

From observations made Monday June 3 in the Annapolis Valley apothecia cups have dried up or are no longer producing spores. Because of this there is no longer any threat of primary monilinia infections, and this will be the last mummy berry post of the 2019 season.

Dried apothecia cup from June 3, 2019

Until next season, for more information on highbush blueberries, monilinia, and aprays please refer to Highbush Blueberry Insect and Disease Management Schedule 2019 and Management of Mummy Berry Disease in Highbush Blueberry.

Mummy Berry 2019 #8

As of this week the majority of apothecia cups have dried up or are otherwise unviable. Because of this the risk of primary monilinia infection has significantly diminished. There is a still a chance that infections could occur at this point, but it is very small and after this Saturday (June 1st) I think the risk will have completely dissipated. At this point it may not be necessary or economically viable to spray. I will put out another blog Monday to confirm the end of primary monilinia infection season.

Dried apothecia cups from May 29, 2019 

Mummy Berry 2019 #7

Since the last mummy berry post there have been three extended infection periods between Tuesday May 14-Wednesday May 15, Friday May 17-Saturday May 18, and Monday May 20-Tuesday May 21. From observations made Tuesday May 21 the majority of  blueberry varieties are past the F2 stage, and some varieties are beginning to approach pre-bloom. Viable apothecia cups are still present with the rain and lack of sun helping them persist, but decline is beginning to occur. If you applied a protective spray before or after the infection period Friday May 10 you should have had control through the week and most of the weekend. If you did not get on another protective spray before the infection period Monday May 20 you can still use a product with back action (Topas, Mission, etc) to achieve control within 72 hours of the infection period. If you have applied two back to back sprays of a group 3 fungicide (Topas, Mission, etc), then a non-group 3 fungicide such as Diplomat 5SC should be used for resistance management before applying an another group 3 fungicide. An ideal time to apply another spray would be Wednesday afternoon when the rains breaks temporarily as it appears there will be two more extended infection periods between Thursday May 23 and Sunday May 26.

As a reminder these recommendation are based off of observations made in the Annapolis Valley and may not be applicable to your region or field. The decision to spray should be based off of observations and weather conditions from your specific site. For more information on highbush blueberry production, mummy berry, and pesticides refer to Management of Mummy Berry Disease in Highbush Blueberry and Highbush Blueberry Management Schedule 2019.   

Mummy Berry 2019 #6

From observations made on Monday May 13, 2019 some blueberry varieties have advanced past the F2 bud stage, and viable apothecia cups are still present. There is potential for an infection period during the rain forecast for Tuesday May 14, 2019 and Wednesday May 15, 2019. If you applied protective sprays for the infection period between Friday May 10 and Saturday May 11, you should still have protection during this next infection period. If you have not applied protection up to this point you can still achieve control by using a product with back-action capability (Topas, Mission, etc)  within 72 hours of the start of the infection period. 

Bud stage from May 13, 2019

Apothecia cups from May 13, 2019

As a reminder these recommendation are based off of observations made at a site in the Annapolis Valley, and may not be applicable to your specific field. The decision to spray should be based off scouting and observation made in your own field. Infection periods only occur when blueberries are at a susceptible bud stage, apothecia cups are present, and weather conditions are suitable. For more information on highbush blueberries, mummy berry disease, and fungicides please refer to Management of Mummy Berry Disease in Highbush Blueberry

Mummy Berry 2019 #5

There is a high likelihood of an infection period during the rain forecast for Friday May 10, 2019 and Saturday May 11, 2019. Rain is also forecast for the majority of next week, and could result in several infection periods. From observations made in the Annapolis Valley some blueberry varieties have reached the majority F2 bud stage, or are more advanced. Mature apothecia cups are also still present, and although some apothecia cups had started to dry up the forecasted wet conditions could slow this process.

Apothecia cups from May 9, 2019

Bud stage from May 9, 2019 

If you applied a protective spray for the infection period Tuesday May 7, 2019, you should still have control until early next week. If you did not apply a protective spray you should still be able to achieve control during the infection period this weekend by applying a spray before the rain on Friday May 10, 2019. If you are unable to get a spray on Friday you can still achieve control by applying a product with back-action capability (Topas, Mission, etc) if applied within 72 hours of the infections period. If you have already applied one of the back action products twice consecutively a non-group 3 fungicide should be used for resistance management. For more information on highbush blueberries, mummy berry disease, and fungicides please refer to Management of Mummy Berry Disease in Highbush Blueberry

As a reminder these recommendation are based off of observations made at a site in the Annapolis Valley, and may not be applicable to your specific field. The decision to spray should be based off scouting and observation made in your own field. Infection periods only occur when blueberries are at a susceptible bud stage, apothecia cups are present, and weather conditions are suitable. I will put out another update this coming Monday May 13, 2019.

Mummy Berry 2019 #4

There is potential for another infection period due to the rain forecast for Tuesday night (May 7th). From observations made Monday May 6th some varieties of blueberries plants have reached majority F2 bud stage, and apothecia cup are still present but beginning to dry up. If you applied a spray for mummy berry before the rain on Saturday, you should still have protection for this infection period depending on the product used. If you have not applied protection for mummy berry up to this point, during the day Tuesday May 7th would be an ideal time. If you are not able to get a spray on Tuesday before the rain, protection can still be achieved by using a product with back action (Topaz, Mission, etc) if applied within 72 hours of the start of the infection period. For more information on blueberries, mummy berry disease, and fungicides refer to Management of Mummy Berry Disease in Highbush Blueberry.

As a reminder the decision to spray should be based off of observations from your own field, as development and conditions can vary widely depending location and other factors. Infection period can only occur when  blueberry plants are at a susceptible bud stage, mature apothecia cups are present, and condition are conducive for disease to develop. These recommendations are based off of a location in the Annapolis Valley and may not be applicable to other sites and regions.
   

Mummy Berry 2019 #3

From the rain forecast for this Saturday May 4th, 2019 it appears that we will have another monilinia infection period. From Observations made Thursday May 2nd in the Annapolis Valley, blueberries are still at or approaching the F2 bud stage. With the increasing temperatures over the weekend and next week, the percentage of susceptible F2 buds will quickly increase. Apothecia cups are also still present and sporulating. If you applied a spray for the previous infection period you may still have protection depending on when the application was made and the product used. If you have not applied a spray already, this Friday May 3rd would be an ideal time before the rain begins. I will put out a blog post early next week confirming whether or not there was an infection period.

As reminder the decision to spray should be based on scouting and observation made in your own field as development and weather can vary considerably between fields. For an infection period to occur blueberries have to be at a susceptible bud stage, apothecia cups have to be present, and weather conditions need to be suitable. For more information on blueberries, monilinia, or pesticides please refer to the Management of Mummy Berry Disease in Highbush Blueberry

 

Mummy Berry 2019 #2

For the primary infection of monilinia to occur you need three things:

1.       Inoculum present: history of monilinia blight.
2.        A susceptible host: vegetative buds have 5mm of green tissue exposed and bud           scales have separated (F2 stage) in the flower buds.
3.        Ideal environmental conditions: wet periods with relatively warm temperatures.

With that in mind it appears that we had our first infection period this past Saturday April 27, 2019.

Observations made Saturday April 27, 2019 from a blueberry field in the Annapolis Valley showed that mature apothecia cups are present (requirement #1), and buds are at the F2 stage (requirement #2). From weather data collected in the Annapolis Valley on Saturday April 27, 2019 there were 15 hours of leaf wetness, and an average temperatures of 7 degrees Celsius (requirement #3). Since all three requirements for infection were met, there was most like an infection period on Saturday April 27, 2019. 

Bud stage from April 29, 2019

Apothecia cup from April 29, 2019

If you did not apply a protective spray before the infection period, you can still achieve control of infections that have already occurred by application of a fungicide with back-action capability (Topas, Mission, etc) within 72 hours of the beginning of the event. For more information on sprays and monilinia please refer to Management of Mummy Berry Disease in Highbush Blueberry.

As a reminder though these recommendations are based off of conditions observed in the Annapolis Valley, Nova Scotia and may not be applicable to your location. Infection periods only occur when bud development has reached the F2 stage, monilinia spore cups are present, and temperature and moisture levels are ideal. The decision to spray should be based on these conditions being observed in your particular field. 

Mummy Berry 2019 #1

From scouting performed Thursday April 25th, some blueberry varieties in the Annapolis Valley are approaching the F2 bud stage (bud scales are seperating in flower bud), and apothecia cups have began to develop but they are still immature (not releasing spores). So far there has not been a monilinia infection period, but if development continues at this rate there is potential for an infection period during the rain forecast for this Saturday. I will send out a blog post early next week to to confirm whether or not there was an infection period.

Apothecia cup from April 25,2019

Bud stage from April 25, 2019 

As a reminder though these observation are from the Annapolis Valley, Nova Scotia and may not be representative of your location. Infection periods only occur when bud development has reached the F2 stage, monilinia spore cups are present, and temperature and moisture levels are ideal. Scouting for monilinia cups, and monitoring plant development and conditions in your specific field is crucial to determining when infection periods occur. For more information on this disease, checkout Management of Mummy Berry Disease in Highbush Blueberry.