Summary:

The influence of sprinkler irrigation and four nitrogen fertilization doses on the height of true millet cv. ‘Gierczyckie’ was determined in a field experiment carried out in the years 2005–2006 on a very light soil at Kruszyn Krajeński near Bydgoszcz. The experiments were run as a two-factorial trial in a split-plot system with three replications. The first row factor – irrigation, was used in the two fol-lowing treatments: without irrigation (control), sprinkler irrigation according to tensiometer indications (-0,03 MPa). The second row factor – differentiated nitro-gen fertilization, was used in the four following variants (doses): 0, 40, 80 and 120 kg N•ha^-1. Investigations included estimation of infestation degree: roots with complex of pathogens, stem base with Fusarium spp., Oculimacula spp. and Rhizoctonia spp. On leaves was observed the occurrence of: powdery mildew, Phyllosticta leaf blight, and other necrotic spots. Irrigation caused the significant increase of Fusarium foot rot as well as the decrease of sharp eyespot. Health status of non-irrigated true millet was de-pendent mostly on rainfall. Lower intensity of Fusarium foot rot was noted in the year characterized by lower rainfall amounts during the vegetation period of true millet, but in case of sharp eyespot – in the year with higher rainfall. The higher nitrogen dose, the significant increase of infestation of true millet roots was oc-curred. Increased nitrogen fertilization under irrigation caused the significant in-crease of infestation of stem base with Fusarium spp. The highest intensity of ne-crotic spots on leaves was observed on plants without nitrogen fertilization, and the lowest one – on plots fertilized with dose 40 kg N•ha^-1. Diseases, which were observed on true millet, did not influence distinctly on grain yield. Only necrotic plots, in case of higher intensity on leaves, caused yield decreases.