The Effect of Fertilization on the Structure of the Aboveground Biomass of Several Cultivars of Jerusalem Artichoke (Helianthus tuberosus L.)

JA (Jerusalem artichoke) cultivars react differently to mineral fertilization. Hence, the aim of this study was to assess the effect of mineral fertilization on the yield and yield structure of this species in terms of its aboveground biomass. The research was based on a field experiment carried out in 2016-2018 in Central and Eastern Poland using the randomized subblock method, in a split-split-plot-dependent system. The factors of the first-order experiment were the cultivars of Jerusalem artichoke (JA) ('Albik', 'Rubik' and 'Violet de Renes'), while the second-order factors were differentiated mineral fertilizers (N0P0K0 as a control object and P-43, K-124, N-100, P43K124, N(50)P(43)K(124)m N100P43K124, and N150P43K124) converted to their elemental forms compared with the full dose of manure. The third-order factors were nitrogen forms, including ammonium nitrate and amide. The aboveground biomass yield and its structure were determined. The tested cultivars did not differ significantly in yield, but had different yield structures. The use of mineral fertilization brought measurable effects in the form of an increase in the yield of aboveground biomass. The 'Albik' cultivar responded best to mineral fertilization, with the highest yield of aboveground biomass being obtained after applying 150 kg N ha(-1) in the form of ammonium nitrate against the background of constant phosphorus-potassium fertilization. The 'Rubik' cultivar responded most favorably to the addition of 50 kg N ha(-1) in the amide form against the background of phosphorus-potassium fertilization, while the 'Violet de Renes' cultivar produced the highest yield of aboveground biomass after the application of 100 kg N ha(-1) in the amide form, including PK fertilization. It was found that it was advantageous to use a combination of nitrogen and phosphorus-potassium fertilization.