What effect do fungicides have on mycorrhiza?

In private gardens, no fungicides, pesticides or other chemical plant protection substances should be used.

For professional applications, we give the following advice:

Pesticides consist of extremely varied chemical agents, which can have negative, neutral, or positive effects on the development of mycorrhizal fungi. If you introduce mycorrhiza products, it is still possible to apply fungicides to combat pathogenic fungi. Harmful fungi differ from symbiotic fungi, and therefore do not experience the same effect from fungicides. Additionally, the majority of fungicides are applied to leaves, and therefore do not come into contact with the mycorrhizal fungi, meaning that they have no effect on the mycorrhiza symbiosis.

So choosing the correct fungicide allows you to apply both products simultaneously, without limiting the function of the mycorrhiza fungi.

We have investigated the effects that different pesticides have on the development of endo- and ectomycorrhizal fungi. If you would like more information on this topic, please feel free to contact us.

You can read about the effects of pesticides on endomycorrhizae in the following publications:

  1. F. FELDMANN, A. DOLEZAL, G. F. BACKHAUS
    Nebenwirkungen von Pflanzenschutzmitteln auf arbuskuläre Mykorrhizapilze als Nichtzielorganismen. Institut für Pflanzenschutz im Gartenbau, Biologische Bundesanstalt für Land- und Forstwirtschaft, Messeweg 11/12, D-38126 Braunschweig.