The influence of nitrogen on the germination of Spergula arvensis L. and Arnoseris minima L.
Investigations were conducted to determine the effect of modified nitrogen supply on the seed germination of Spergula arvensis and Arnoseris minima. The effects of nitrogen in aut- or synecological (ecosystem) conditions were analysed. The germination of Spergula arvensis and Arnoseris minima was found to be promoted by N-containing solutions (NH4NO3). The effects were suggested to be N-specific, as was shown when polyethyleneglycol (PEG) was used as a comparison. The germination rate of Spergula arvensis was found to be greater than that of Arnoseris minima. The germination rate of both species was distinctly slower in NH4NO3 solutions than in Aqua dest. Spergula arvensis was found to germinate in light as well as in darkness and had no primary dormancy, and therefore could germinate instantly. Secondary dormancy, which took place within a few weeks, was found to lead to a reduction in the germination rate.