Fig. 3
From: Effect of bioeffectors and recycled P-fertiliser products on the growth of spring wheat
Total aboveground biomass of wheat plants in the UCPH experiment from the first harvest (32 days after sowing, black symbols) or the second harvest (54 days after sowing, grey symbols) as a function of the P concentration in the youngest fully developed leaf from one plant measured at 25 days after sowing. Only data from three replicate pots were included for each treatment and only BE0 treatments were included. P treatments are: negative control (P0), TSP, low-grade TSP (SP), sewage sludge (SS), sewage sludge ashes (SSA), fibre fraction of pig manure (FFPM), compost of sewage sludge and garden/park waste (Compost). The data are fitted to three-parameter functions of the form \(y = y_{0} + a \cdot \left[ {1 - e^{{\left( { - b \cdot x} \right)}} } \right]\)