Does coir inhibit fungus gnat development?
In a laboratory study, we determined how peat and coir affect the development and survival of fungus gnats. Peat, sterilized peat and peat with added yeast (as a food source for the fungus gnats) were compared with coconut coir, sterilized coir and coir with added yeast. Individual Styrofoam cups were filled with this media, and 20 fungus gnat eggs were added to each cup. The number of fungus gnat adults emerging from the different media was recorded after two weeks. The counts were continued for an additional two weeks, at which point almost all the adults had emerged. Very few adult fungus gnats emerged from either peat or coir when a food source was not provided, independent of whether the peat or coir had been sterilized (See Figure 1, page 20). When yeast was added, about 12 (60 percent) of the 20 eggs in each cup developed into adults. The number of adult fungus gnats that had emerged was similar for both peat and coir. The developmental time from egg to adult was also similar fo
