New aspects to the control of fungus gnats (Bradysia pauper) in the biological production of potted herbs in Germany.

摘要

During the biological production of potted herbs in greenhouses, the larvae of fungus gnats can develop to such high populations in the substrate, that the growth of the herbs is significantly reduced by their feeding. Particularly the addition of quickly decomposing organic amendments prior to potting, can cause a dramatic increase of the fungus gnat larvae populations in the substrate. If such freshly mixed substrates are stored for about 5 months prior to potting, the risk of fungus gnat population development is drastically reduced. To further optimize the effect of reduction of fungus gnat development, the filling of the pots with separate substrate layers is recommended. The bottom layer of the pots is filled with well composted bio-substrate. The next layer is composed of some organic additive, functioning as organic fertilizer. The top substrate layer is composed of the same substrate, as is used for the bottom layer of the pot.