Uptake of nitrogen, phosphorus, and potassium by mat rush and effects of nitrogen and potassium fertilizers on plant yield and quality in paddy field soil

Uptake of nitrogen (N), phosphorus (P), and potassium (K) by Mat Rush (Juncus effusus L. var. Decipiens Bchen) (cv. Gangshan 3) and the effects of N and K fertilizers on yield and quality of paddy field-grown Mat Rush were studied. The results showed that plant tissue N and K concentrations gradually declined with plant growth, ranging from the maximum of 3.32% and 3.48% to the minimum of 1.66% and 1.79%, respectively. Plant tissue P concentration declined slightly during early growth, then increased in effective-stem tillering stage. Highest P concentration was 0.36%. Maximum accumulations of N, P, and K in foliage were N 293.9 kg ha(-1), P2O5 59.7 kg ha(-1), and K2O 374.5 kg ha(-1), respectively. In comparison with the control, N fertilizer significantly increased stems per hill (SPH), average stem length (ASL), long stem percentage (LSP), and stem chlorophyll content (SCC), beneficial to stem quality improvement, leading to significantly increased yield, and meanwhile caused higher stem flowering rate (SFR) which would deteriorate the stem quality. There was no significant difference in stem yield and quality between N-1 (450 kg ha(-1)) and NZ (900 kg ha(-1)). Potassium fertilizer significantly improved all quality parameters and yield, except for SFR. Rates of 450 kg ha-1 of N fertilizer and equal amounts of K fertilizer applied to paddy fields appear optimum to obtain high yield and quality in Mat Rush production.