2.1. Laboratory analyses
At the end of each vegetation period 5 randomly chosen plants from
each plot were dug and measured and their raw material was dried at
50 °C in a drying chamber. For analysis of active substances
phenylpropanoid content (expressed as the sum of rosin, rosavin and
rosarin) HPLC method using Prostar apparatus (Varian) with DAD detector
equipped with 5 μm C18 250 mm×4.6 mm column (Phenomenex)
according to previously described procedures (Węglarz et al., 2008) was
used.