Seamaiden
Living dead girl
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More people should know this and more people should be talking about this instead of debating it. It's a fact. Read the label, do even the most cursory research on it and I guarantee that you will learn what is known--single-mode action 'cides can easily force pathogens to become resistant. Therefore, it is highly important that people who regularly battle PM know and understand that they MUST incorporate other methods of control, especially those that use physical barriers and multi-site modes of action against the fungi.
Don't believe me? Read it for yourself.
Maybe I should put up a poll to find out how many people don't know this, yet are using this product rather freely (read: carelessly). Naw, maybe the responses I get will be enough.
Before someone pops in and says that the label doesn't say it will make resistant powdery mildew, please, let me put your mind at ease here--PM is fungi, and there are many species of the PM fungi. Therefore, the label needs to be more broad in its discussion.
But wait, there's more evidence that speaks to the real truth of the matter.
http://vegetablemdonline.ppath.cornell.edu/NewsArticles/Cuc_Cntct_Fcides.htm
Don't believe me? Read it for yourself.
That's a single-site mode of action. But wait, there's more, and it's not that hard to find.Eagle 20 Label said:Eagle 20EW is a systemic fungicide whose active ingredient, myclobutanil, inhibits the synthesis of ergosterol, an important component of fungus cell walls. Myclobutanil, a demethylation inhibitor (DMI), hinders sterol synthesis, which restricts
cell wall development in targeted pathogens.
Eagle 20 Label said:General Use Precautions
Fungicide Resistance Management
Eagle 20EW belongs to the sterol demethylation inhibitor (DMI) class of fungicides and is classified as a Group 3 Fungicide by EPA. Since certain fungi can develop resistance to this class of products, the use of Eagle 20EW should be part of a resistance management strategy that includes alternation and/or tank mixing with fungicides of different modes of action. Consult your local or state agricultural authorities for resistance management strategies that are appropriate for your disease management program.
Maybe I should put up a poll to find out how many people don't know this, yet are using this product rather freely (read: carelessly). Naw, maybe the responses I get will be enough.
Before someone pops in and says that the label doesn't say it will make resistant powdery mildew, please, let me put your mind at ease here--PM is fungi, and there are many species of the PM fungi. Therefore, the label needs to be more broad in its discussion.
But wait, there's more evidence that speaks to the real truth of the matter.
http://vegetablemdonline.ppath.cornell.edu/NewsArticles/Cuc_Cntct_Fcides.htm
Just tell me more evidence is needed, I'll find it.Margaret Tuttle McGrathAssociate Professor
Department of Plant Pathology
Long Island Horticultural Research and Extension Center
Cornell University
Protectant (contact) fungicides are an important component of the fungicide program recommended for managing powdery mildew in cucurbits.
They play a critical role in delaying development of resistance to systemic fungicides.
The fungus causing cucurbit powdery mildew has an established track record worldwide of being able to develop resistance to systemic fungicides.
Most systemic fungicides are at risk for resistance development because they have single-site mode of action. Thus modification of one gene in the pathogen may be enough to enable the pathogen to resist the action of the fungicide.