This year my strawberries were hit hard with Anthracnose Fruit Rot.
Various extension services say under the right conditions 90 percent of the fruit can be infected within a week or less - confirmed - fungicides are useful as preventatives (Captan and more restricted chemicals) but can’t control an infection. The recommendation is to burn all plants, and start with fresh disease-free plugs. Some recommend waiting 2 years to replant an infected field as the pathogen can survive in the soil.
I’m a lazy home grower with too many strawberries.
[screened berry cage in front, thrip-netted orchard at the other end of the cold frame]
These are grown in Rootmaker pots, and watered from below.
It was a prime year for Anthracnose here on the coastal plain of Virginia - warm, humid, and crowded production since I planted all the descendants. This is the 3rd year with these plants and offspring. All are susceptible varieties Chandler (especially susceptible), Clancy, Galletta, Jewel.
My strawberries had been trouble-free until this year - my only spray was a copper/oil spray in early spring. In hindsight, I should have been spraying every 10 d with Captan.
I don’t relish the idea of burning up the plants and burying the used planting media,
but I’d prefer not to go through this again. I should probably do this the next dry spell so they don’t infect my blueberries.
Any advice from those who know about Anthracnose or have been through this before?
I too have only had gray mold and captan does prevent it. I sprayed for three years, and that was 4 years ago. It has not resurfaced. Probably brought in on plants I bought. Appears not to be around at all.(whew!)
Once you have it, the best bet is to plant only resistant varieties.
I had not experienced anthracnose until maybe 20 years ago in North Carolina.
I’m positive the soil already had the pathogen, despite me clearing pine saplings to create a
garden spot.
i had this issue 5 yrs ago.on a earliglow raised bed. i dug out all the plants and soil into a high mound and built a large hot fire on it. scraped the ashes off, sprinkled some sulfur in there to lower ph and replanted with a resistant variety. it worked and has been producing clean berries ever since. yes it sucks to get rid of your plants but strawberry plugs are pretty cheap or you could get less of them and plant out runners for free from that 1st batch.make sure to sterilize your pots and tools. i used diluted vinegar. good luck!
Oops. Thanks for the notice about the screwed up title.
Grey mold another doosey.
Grey mould of strawberry, a devastating disease caused by the ubiquitous necrotrophic fungal pathogen Botrytis cinereahttps://bsppjournals.onlinelibrary.wiley.com/doi/full/10.1111/mpp.12794
Let’s see if somebody else has more knowledge about this pathogen and strawberries.
I’ve really never seen a bad case in strawberries and have limited experience dealing.
I’d make sure if I accepted free plants from someone that the plants didn’t have diseases.
Then, if I had a strawberry bed that had a bad infection, I’d find some other spot to grow strawberries in the future. (And order new plants from a nursery free of diseases. (But, I realize some have small lots and little room for rotation of plants.)
Sorry I’m unable to recommend a variety that is definitely immune to anthracnose.
In strawberry anthracnose happens as a symbiosis with gram-negative bacteria which get quorum sensing function triggered by Ferric Oxide.
It is an indicator that Iron is not staying chelated.
Or that microbes exist in soil which are unchelating Iron.
Or that poor soil aeration is resulting in mycorrhizae & wild soil yeasts precipitating Copper by producing Ethyl Alcohol from root sugars in the absence of O2.
In such conditions Copper precipitates into Copper Carbonate.
Copper then is not present as an enzyme for making Iron Ligands & for Iron transport enzymes.
Too much Nickel also increases activity of Botrytis Cinerea which resembles anthracnose.
Boron deficiency can also result in anthracnose problems.
Boron is used in the quorum sensing functions of gram-positive bacteria which help keep gram-negative bacteria from transitioning from benign to invasive pathogenic.
Once in pathogenic mode the synergistically facilitate anthracnose compromising cell structure.
Check roots for Ferric Oxide damage.
Test soil & water.
Citric Acid can be used for pH balancing to reduce the chances of Iron unchelating.
Best Boron treatment is Sugar Mover as contains Molybdenum.
Molybdenum is part of FeMo-Cofactor enzyme which fixes Nitrogen.
Be sure that soil is not deficient in Manganese if using sugar mover or pH goes up.
It is needed for nitrogen conversion of Ammonium into Nitrate.
Molybdenum will prevent Urea from building up in leaf perimeters & in fruit.
Anthracnose fungi feeds on Urea!
Molybdenum will facilitate Nitrogen being turned into a protein which strengthens cell walls.
Having Magnesium too high in relationship to Calcium results in thin cell walls with too little Calcium Pectate.
Calcium Pectate is needed for cell wall integrity.
Boron helps stem cells assimilate Calcium.
Calcium can only be assimilated by stem cells.
Chances will only become effective in the meristem stem cells at time of treatment nutrient change.
Not in adult tissue.
Sugar Mover should be used at (1/100) teaspoon per gallon of water sprayed into the crown apical meristem.
Don’t put in the soil or water.
Putting extra Boron in the water will hyperventilate the leaf stomata breathing cells.
When Boron is added to the water it goes from the roots to the stomata first, then back to the nodes.
If air is dry Boron with precipitate at the stomata.
Boron is needed primarily in the stem cells of nodes & crown apex.
Questions?
It’s not Botrytis - I checked after you brought it up.
The strawberries are in pots in gritty, quick-draining, pH controlled media with micronutrients including boron and moly. I don’t use urea.
Good to know that Immunox works for you.
Apparently Sweet Charlie, which is available, unlike Bish is resistant to Anthracnose, but it’s susceptible to Phomopsis and Botrytis - can’t win.
Do you even have Anthracnose in Maine?
Times like this I sure miss the Maine summers.
@zeppley
All plants convert excess Ammonium & Nitrate to Urea.
Mycorrhizae & yeast use Nickel enzymes to convert Ammonium & Nitrate to Urea.
Calcium & Molybdenum synergistically work together to retrieve the Urea!!!
Iron-EDDHA is the best Iron source to prevent pathogenic behaviors from being quorum sensing triggered.
If pH goes to low, Molybdenum precipitates.
I suggest actually testing the solution for all nutrients & keeping pH at higher end of the acceptable range to maximize the water solubility of Molybdenum & Boron.
