Systemic fungicide

[tam91]

The nice men who are letting me garden on their property are farmers, so I'm sure they are probably licensed to purchase any desired agricultural products. I was wondering, if it would be a good idea to take advantage of that (if they are willing) to get some systemic fungicide for my tomato plants.

Would those work better than daconil/etc?
Is they easier to use (i.e. don't have to reapply after rain)
Can anyone recommened a product?
Any reason not to do this? (other than me being careful and not drinking it etc.)

[carolyn137]

Originally Posted by tam91

The nice men who are letting me garden on their property are farmers, so I'm sure they are probably licensed to purchase any desired agricultural products. I was wondering, if it would be a good idea to take advantage of that (if they are willing) to get some systemic fungicide for my tomato plants.

Would those work better than daconil/etc?
Is they easier to use (i.e. don't have to reapply after rain)
Can anyone recommened a product?
Any reason not to do this? (other than me being careful and not drinking it etc.)

I wouldn't use ANY systemic on ANY edible crops and my good farmer friend Charlie didn't either and he had such a license as you mentioned.

I'm not sure how a systemic would help prevent the common fungal foliage diseases since the prevention rests with preventing fungal spores from being able to attach to the specific attachment sites on the leaf surface.

And Daconil does that.

[tam91]

OK, I must be mistaken. I thought I had read that commercial farmers used something systemic that worked better, but it was not available to individuals. I'll have to see if I can find where I saw that, or maybe I imagined it

[kath]

tam, you weren't by any chance thinking about Oxidate, were you? It's a product that was discussed a while ago and it's not available in sizes that are practical for home gardeners, so the cost is high unless you can split it with someone. It's available through Johnny's Selected Seeds if you want to have a look at the product but it's not a systemic and it is available for individuals to purchase if you want a huge container.

[RayR]

Any systemic that would require a license is probably pretty dangerous toxic stuff.

On the safer side of systemics:

Mono-and di-potassium salts of phosphorous acid (Excel LG a.k.a. Plant Doctor, Agri-Fos) is pretty effective from my experience against Oomycete pathogens. Downy Mildew on Squash and Sunflower are the only Oomycete pathogens that I've had and seen it work on. No Late Blight yet this year so I can't evaluate it on that. Don't really want to either. It doesn't have a direct mode of action against true fungal pathogens but it may induce systemic resistance in the plant. I'm using it in con★★★★★★★★ with biocontrols on Tomato. I haven't had any serious outbreaks of Early Blight or Septoria so maybe it is contributing, can't say for sure how much.

Azoxystrobin is a broad spectrum systemic fungicde used in farming. Ami uses it since it is available in smaller quantities in Europe for gardeners. Pretty expensive here unless you have others to share it with. There are concerns that overuse is causing pathogens to develop resistance.

[kurt]

http://www.globalchangeblog.com/2010...apse-disorder/ I get to talk to alot of beekeepers and finally some headway in the cause of CCD.In my neiborhhood we have made a effort not to use ANY chemicals until the cause is identified.

[greentiger87]

It really depends on what problems you normally have to deal with. Personally, I wouldn't use a systemic other than a resistance elicitor/inducer or phosphite/phosphorous acid fungicide.

Strobilurin fungicides, like azoxystrobin, are pretty effective against early blight.

The fungicides effective against late blight are not significantly better than preventative spraying with chlorothalonil or mancozeb.

Also consider Milsana (Reynoutria sachalinensis = Giant Knotweed extract) and Actigard (Acibenzolar-S-methyl) as resistance elicitors.

[barkeater]

The only systemic fungicide I knew commercial tomato farmers to use (80's-90's) was called Ridomil. It was primarily to prevent the fruit rots from soil pathogens from the tomatoes sitting on the ground, as most tomatoes were grown and left to sprawl on bare ground in New Jersey back then. I was one of a few that grew on plastic back then.

[tam91]

Thanks everyone. I thought I was remembering something, but apparently I was wrong. Not the first time (or the last I bet!).

[amideutch]

Strobilurin fungicides, like azoxystrobin, are pretty effective against early blight.

Add Anthracnose, Mold, Buckeye Rot, Septoria Leaf Spot, Target Spot and Late Blight to the list.
It is a systemic as well as a curative fungicide which can be applied as a drench as well as a foliar. Strobilurin's are derived from mushrooms. Ami

[tam91]

Interesting, I may have to look into that one.

[greentiger87]

In the US, everyone is freaking out about strobilurin resistance though. Because of the mechanism of action, strobilurins are really prone to the formation of resistance. That's why it's so highly regulated.. it's actually pretty benign as far as human safety goes. It is pretty toxic to marine life, but it gets biodegraded quickly in the soil.

The resistance problem has been huge disaster in the wheat industry, considered a major failure of policy and enforcement.

http://www.ces.ncsu.edu/fletcher/programs/plantpath/

Take a look at those spray guides to see exactly what farmers are recommended to use today. It's kind of mindboggling really...

[amideutch]

In the US, everyone is freaking out about strobilurin resistance though.

Even hear in Germany the labels are quite explicit as to their frequency of use. I alternate my applications of Azoxystrobin with EXEL LG and Actinovate. A lot of folks start seeing Late Blight in the latter part of the growing season in con★★★★★★★★ with the rains. So for me my applications of EXEL and Actinovate will normally cover the early season diseases. Then later on I bring out the big gun and alternate it's application with EXEL/Actinovate. So normally my applications of Azoxystrobin are 4-6 applications per season. Ami