Browsing by Subject "radish"

Sphagnum moss could be used as a substitute for Sphagnum peat as a growing medium. It has the same positive physical properties as peat and it is also a more sustainable option. However, there are some indications that Sphagnum moss may have some inhibitory effects on vascular plant seed germination and seedling development. The aim of this study was to find out whether this is true and due to the low pH of different Sphagnum moss species. The tested moss species were Sphagnum fallax, Sphagnum medium, Sphagnum rubellum and Sphagnum spp. The seed germination on Sphagnum moss substrate was tested with lettuce, radish, basil, pine and ryegrass. Also, two additional seed germination experiments were done with lettuce. Seedling growth experiment on Sphagnum substrate was tested with lettuce. The first germination experiments indicated that the dicotyledon species basil, radish and lettuce are sensitive to the allelopathic effect caused by Sphagnum moss. In the case of ryegrass and pine no indication of seed germination inhibition was found. The two additional germination experiments confirmed that Sphagnum moss and white peat substrates and Sphagnum moss and white peat organic matter/water extracts were inhibiting lettuce seed germination. Added lime didn’t conclusively explain the inhibition in germination percentages of Sphagnum moss substrate when compared to control treatment gauze. Only in the case of radish the raised pH had positive effect on the germination percentage. Therefor it was concluded that the low germination percentage is not explained only by the naturally low pH of Sphagnum mosses and Sphagnum mosses’ other characteristics should be investigated in the future. In the seedling growth experiment done with lettuce on Sphagnum medium growing medium there was no indication of allelopathic effect on seed germination or seedling development. The allelopathic compounds were thought to have been lost in this experiment through leaching when the substrates were watered.