Dr hab. inż. prof. UTP Stanisław Rolbiecki

Dr inż. Roman Rolbiecki

Mgr inż. Piotr Czop

Effect of drip irrigation and nitrogen fertilization on yields of onion cv. 'Kutn-owska' on the sandy soil in the region of Bydgoszcz

The aim of the study was to determine the effect of drip irrigation and ni-trogen fertilization on yields of ‘Kutnowska' onion grown on the very light soil in the region characterized by rainfall deficits during the vegetation period. Field experiments were carried out in 2003-2004 at Kruszyn Krajeński near Bydgoszcz on a soil belonging to the VI class (degraded black earth belonging to the very poor and poor rye complex). Field water capacity in the layer 0-50 cm amounted 57,5 mm, and the effective useful retention was 29,3 mm. Field trial was established and conducted in three replications as two-factorial experiment in split-plot design. Irrigation was the first order factor used in the two variants: without irrigation (control) and drip irrigation at - 30 kPa. The second order factor was nitrogen fertilization: N0 - 0 kg N ha-1(control), N1 -70 kg N ha-1, N2 - 140 kg N ha-1, N3 - 210 kg N ha-1. Drip irrigation was the basic yield-creating factor, securing the cultivation of onion on the loose sandy soil. Marketable yield obtained from ir-rigated plots - average for years and nitrogen doses - amounted 33,2 t•ha-1. Un-der conditions of optimum moisture secured by irrigation, the ...