Effect of varied NPK fertilisation on the yield size, content of essential oil and mineral composition of caraway fruit (Carum carvi L.)

Fertilisation is the main factor stimulating yields of herbaceous plants, including yields of active substances per area unit. The aim of the research was to evaluate the yielding and chemical composition of fruits of cv. Koñczewicki caraway grown in a pure stand and supplied different rates of mineral fertilizer. The results are derived from a controlled, one-factor, micro-plot experi- ment set up with four replications in a split-plot design. The experimental factor consisted of NPK mineral fertilisation introduced into soil at the following rates per hectare: A 0 – without mineral fertilisation, A 1 – 103.9 kg NPK (37.5 kg N+17.6 kg P+4 8.8 kg K), A 2 – 209.8 kg NPK (75 kg N+35.2 kg P+ 99.6 kg K), A 3 – 314.7 kg NPK (112.5 kg N+52.8 kg P+ 149.4 kg K). Mineral fertilisation in the control increased the caraway fruit yield, the yield of essential oil as well as the content of total nitrogen. The rates of 209.8 kg NPK ha –1 and 314.7 kg NPK ha –1 caused a distinct decrease in the content of essential oil in cara- way fruits compared with the unfertilized treatment and with the fertilisation rate of 103.9 kg NPK ha –1 . Mineral fertilisation, in general, significantly decreased the content of total phosphorus, calcium, magnesium and sodium, although it did not differentiate sub- stantially the content of potassium in caraway fruits.