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Lodi, California

does a systemic fungicide kill mycorrhizae? If the fungicide flows through out the whole plant, including the roots, wouldn't the mycorrhizae be killed?

1/20/2014 5:09:42 PM

Anamosa, IA BPIowegian@aol.com

Phosphite systemic fungicides like Agri Fos aren't supposed to bother mycorrhizae if used according to the label.

1/20/2014 7:30:09 PM

BC, Canada

From what I have been able to read it seems like a complicated question, or answer. Both when used have demonstrable beneficial effects on plant growth, so, It shouldn't be a problem. In other words if it works- go for it. It seems to depend on the fungicide and the species of fungus. There are a number of reports available online to read. I have read a few and I would sum it up as "it ain't a real problem." But I wouldn't mix them together to apply either.
And as always- Please Please follow directions on any pesticide- the directions are there not just for health safety but for efficacy of the product as well. More isn't necessarily better.

1/20/2014 7:45:35 PM

Pa

no one seems to really know the answer to this often asked question. What we need is a phd level biologist to weigh in. From what I have gathered, yes, the nuclear level fungicides, the ones that really work effectively, are harmful to myco. If disease is a problem then they are a necessary evil whose benefits outweigh their detriments. Clearys, medallion, are known to be harmful to myco. On one hand it seems simple, fungicides kill fungus, myco is a fungus.

1/20/2014 8:36:20 PM

Muddy Waters

I think the guys that use anything that kills the good stuff along with the bad stuff.Chemical drenches and such.Then they put it all back in again.So If you think the systemic fungicide kills the mycorrhizae,simply reinoculate the plant after a day or two to be sure.Plus the mycorrhizae should have given you a bigger root system,you wont loose that root system even if you kill a few thousand or millions of the little buggers.Make sense?If not shoot me e-mail

1/20/2014 9:43:34 PM

Central Illinois

Here is an article that may help

http://www.planthealthcare.com/pdf/Myconate/Fungicide%20effects%20on%20Mycorrhizal%20Fungi%20and%20Root%20Colonization%208-2009.pdf

1/21/2014 8:27:30 AM

Georgetown, Ontario

I've posted this chart several times before. Save it in your favorites for future use. Certain products are fine and other aren't. http://www.usemykepro.com/pdf/compatibilite%20pest-mycorrhizae.pdf

1/22/2014 10:00:42 AM

Mill Bay, British Columbia

Great links baitman and PS...thanks.

1/23/2014 12:45:43 PM