Anti-fungal sprays during rainy times

[RayR]

Originally Posted by KathyDC

Can you elaborate - what products do you use, how? Soil drench, I guess? I'm curious because early blight almost always shows up in my garden, so I'd love any pointers.

This whole thread turned into a fascinating discussion!

Once temps rose to above 90 I switched to alternating mancozeb, daconil and copper -- unfortunately a few plants are showing fungus issues as of last week despite my best efforts at keeping ahead of it, BUT, at this point in the season it's usually much worse and more plants affected. So, I have some tweaks to make on my spraying regime for next year - but I'll call this year a success so far anyway, because it's usually a lot worse by now.

There are benefits that may help with some other plant pathogens and pests also but we'll stick with using mycorrhizal fungi to trigger SAR against Early Blight (Alternaria solani) for now since that has been well researched.

You have to inoculate your seedlings roots early for the mycorrhizal fungi to infect the roots and start to grow out as an extension of the root system . It takes about 2 weeks this part of the mycorrhizal association to occur, the spores will only germinate in the presence of living roots. I inoculate as soon as the seed is planted, you could do it a little later of course, but the sooner the better. When transplanting the seedling in their final home, I will again add mycorrhizal inoculant to my organic pre-plant root dip (for me that is fish hydrolysate/seaweed and BioAg's FulHumix), as the roots grow out the new spores will again be signalled to germinate and make their home in the roots. That's all that needs to done on your part. Just one caveat, don't use any fertilizers with high available water-soluble nitrogen or phosphorous until after the seedling has been in its final home for 3 weeks to a month. High amounts of water-soluble N and P will inhibit mycorrhizal colonization and that's not good. It's more of a concern with synthetic water-soluble fertilizers than most organic fertilizers where the nutrients are converted to plant available water-soluble forms more slowly over time.
You can use any inoculant like MycoGrow Soluble from fungi.com, Great White by plantrevolution.com, or similar. I like to use multiple species high spore count mycorrhizal inoculants like these, plus they have a boat load of beneficial PGPR bacteria and Trichoderma also.

Science Stuff:
BBC - Earth - Plants talk to each other using an internet of fungus

Enhanced tomato disease resistance primed by arbuscular mycorrhizal fungus

Arbuscular mycorrhiza reduces susceptibility of tomato to Alternaria solani

Interplant Communication of Tomato Plants through Underground Common Mycorrhizal Networks

[tryno12]

Is Mycogrow the same as as Mycoblast?

[RayR]

Originally Posted by tryno12

Is Mycogrow the same as as Mycoblast?

Yes, similar Myco Blast has 4 species of endomycorrhizal fungi, 4 species of beneficial bacteria and Trichoderma.
Mycogrow has 9 species of Endomycorrhizal fungi and 9 species of Ectomycorrhizal fungi
Great White has 9 species of Endomycorrhizal fungi, 7 species Ectomycorrhizal fungi , 13 species of beneficial bacteria and 2 species of Trichoderma

Ectomycorrhizal fungi only associate with certain trees, mostly conifers, oaks and hardwoods and form above ground fruiting bodies (mushrooms)

Typically the common workhorse species you'll find in all endomycorrhizal innoculants are Glomus intraradices, G. mosseae, G. aggregatum, G. etunicatum, the first two are the most prolific in nature around the globe. Glomus intraradices has been found everywhere except Antarctica. Glomus mosseae was the species used in the studies of the SAR effect against Early Blight on tomato.

Types of Mycorrhizal Plants

Mycorrhizal Status of Plant Families and Genera

[KathyDC]

Regarding your note about N/P rich fertilizers, I use Texas Tomato Food - soil drench weekly. Would that be problematic with your myco innoculant method?

[tryno12]

Thank you for the info Ray

[RayR]

Originally Posted by KathyDC

Regarding your note about N/P rich fertilizers, I use Texas Tomato Food - soil drench weekly. Would that be problematic with your myco innoculant method?

Texas Tomato Food's liquid NPK is 4.0-2.7-6.5 and at the recommended rate of 1tbls/gallon, in general that shouldn't be a problem but do you use the same rate at the seedling/transplant stage and when do you start feeding? What does Urban Farms recommend? I haven't used TTF but I have used hydroponics grade liquid nutrients and for a seedling 1tbls (15ml)/gallon that would be an excessive amount. I would think cutting the rate to 2ml or 3ml/gallon would be more than sufficient for a young seedling in the vegetative phase and more friendly to successfully kicking off the mycorrhizal association as well as the growth of the other beneficial microbial colonies.
Since TTF is a hybrid synthetic/organic fertilizer and even does contain some mycorrhizal spores, I would assume they have some recommendations for a safe application rate for young seedling in soil.

[tryno12]

hi Ray, I put my Mycoblast in the freezer for a week or 2 last summer, it is going on 2 years old and kept in the cool dark garage. Would you think it will be as effective for next springs seedlings as it was?
Thank You
Pete

[RayR]

Originally Posted by tryno12

hi Ray, I put my Mycoblast in the freezer for a week or 2 last summer, it is going on 2 years old and kept in the cool dark garage. Would you think it will be as effective for next springs seedlings as it was?
Thank You
Pete

Freezing any microbial inoculant is not recommended. Dormant mycorrhizal spores are pretty hardy and can handle a wide variety of environmental conditions, but freezing them is not going to extend their viability. Dr. Mike Amaranthus says "Cold temperature, even freezing, does not affect the viability of mycorrhizal propagules that are most commonly used as inoculum. High temperatures, above 140 degrees F, damage mycorrhizal propagules and should be avoided."
Just keep the powder dry and in a cool place. The standard manufactures shelf life is considered to be 2 years but Dr. Mike says you'll lose about 10% mycorrhizal spore viability per year when stored properly after 2 years. So ya, it'll still be effective enough for seedlings next spring.

[KathyDC]

To be honest I don't remember exactly as it's been some time since I transplanted out, but I don't think I remember any special dilution instructions from them for seedlings vs established plants vs fruiting. They recommend 1Tb/gal in general. I typically mix up 3Tb in a 3gal bucket, and that usually is enough for me to soil drench 5-6 plants, so I don't think it would be too overwhelming. But I'll take a closer look at their instructions.

They're really responsive and happy to answer questions about best applications so that's always possible too.

EDIT: Actually it looks like they recommend using their all-purpose veg fertilizer until fruit set, then switching to TTF:

https://theurbanfarm.com/legrpa.html