Toxicity of new fungicides for eukaryotic microorganisms isolated from the gut of the food-important vegetable pollinator Bombus terrestris L.

Currently, there is a trend in decreasing of the number of pollinators, which is already a matter of food security. Bumblebees Bombus terrestris L. are economically important pollinators of vegetables and other agricultural crops. Recently, it has been suggested that the synergistic effect of pesticides and diseases that affect pollinators contributes to a sharp decline in the number of pollinators. In this work, we investigated the effect of new biodegradable fungicides on eukaryotic microorganisms Penicillium commune and Rhodotorula mucilaginosa isolated from the gut of Bombus terrestris L. larvae. It was shown that the new fungicides studied can inhibit the growth of both mycelial eukaryotic microorganisms and yeast eukaryotic microorganisms. Among the studied substances, the most effective was fungicide 2. The studied substances are selectively toxic only for eukaryotic microorganisms and do not have a toxic effect on animals, in particular insects, and can be used to treat insect pollinator infections caused by fungal microorganisms. It was noted that the new fungicides are more toxic to yeast than to mycelial fungi.