Effect of compounds used for soaking narcissus bulbs on mycelium coverage of bulbs and substrate

In the experiments, two compounds were used: hydrogen peroxide with silver (H2O2-Ag+) and captan, pyraclostrobin + boscalid and methyl thiophanate + tetraconazole to soak narcissus bulbs before planting for the period of 20 minutes. The bulbs were planted in such a way that 2/3 of the bulb was above the surface of the substrate. All the pots with bulbs were subsequently placed in plastic boxes and transferred to a cooling chamber adjusted precisely for 9 °C and 94–99% air humidity. During the rooting of the bulbs in the cold room after 4, 8, 12 and 15 weeks, and then in the greenhouse after cutting the above-ground parts, the observations of the bulbs and percentage substrate coverage by the fungi most frequently isolated in the previous observations. The research showed that H2O2-Ag+ and fungicides used for soaking significantly limited the fungal development on bulbs and also on the substrate during the rooting period in the cold store and after they were placed in the greenhouse until the flowering.