Fertiliser response of triticale in a long-term experiment in Nyirlugos

The paper reports the results achieved in the 32(nd)-36(th) years of a long -term small-plot fertilisation and liming experiment set up on acidic sandy brown forest soil in the Nyirseg region. Characteristics of the experiment al soil: PH(KCl) 4.5, humus 0.5%, CEC 5-10 mgeq/100 g in the ploughed layer . The topsoil was poor in all five macronutrients (N, P, K, Ca, Mg) and the groundwater depth was 2-3 m. On average 100 kg N, 120 kg P2O5 and K2O, 500 kg CaCO3 and 210 kg/ha MgCO3 was applied annually in the form of 28% calci um ammonium nitrate, 18% superphosphate, 60% potassium chloride, 95% powder ed limestone and 18% powdered dolomite. In autumn 1997 four years' supply o f PKCaMg fertilisers was applied. The following conclusions could be drawn: 1. As the result of regular N fertilisation the PH(KCl) value in the topsoi l dropped to 3.5, while it rose to 5.8 after the addition of Ca+Mg. The P a nd K supplies of the soil became satisfactory after P and K fertilisation. 2. The grain yield rose from 0.9 t/ha in the control to 2.5, 5.3 and 7.9 t/ ha, respectively after fertilisation with N, NPK and NPKCaMg in 1998, when the rainfall distribution was exceptionally favourable. In the earlier dry years, however, the fertiliser effects were much lower or non-existent. 3. If a grain yield of 6-8 t/ha is to be achieved 600-800 spikes/m(2) are r equired. If the rainfall supplies are ideal and satisfactory soil pH and nu trient supplies are provided, the fertility of this poor sand may be outsta nding and a satisfactory plant stand can be developed. 4. After dry years or alter over-fertilisation with N substantial N after-e ffects can be expected even on this soil. The thin clay layers occurring at a depth of 60-80 cm retard the leaching of N, thus making it available for the following crop. Approximately half the N taken up in 1998 on plots giv ing high yields may have originated from the soil N reserves and the rainfa ll, while the other half was covered by the fertiliser N applied in that ye ar. 5. The incorporation of N preceded dry matter accumulation, so the tritical e had already taken up the larger part of the N by the end of the shooting stage. A small degree of further accumulation was observed in the NPKCaMg t reatments, while in the control plots the N reserves dropped to half when t he leaves withered. Between the end of shooting and maturity no real dry ma tter accumulation took place except on very fertile soil.