Summary:

The aim of the study was to determine of the influence of drip irrigation and sprinkler irrigation on the quantity and quality of yield of selected medium early potato cultivars. Field experiments were conducted on the soil classified to IVb valuation class and good rye complex in 2001-2003 at Kosobudy (Community of Brusy), Pomerania Voivodeship. Effective useful retention in the soil layer of con-trolled moisture (0-40 cm) amounted 29,5 mm.The experiments were carried out with two-factorial split-plot design, with four replications. The first-row factor was irrigation: O - control plots (without irrigation), K - drip-irrigated plots, D sprinkler-irrigated plots. The second-row factor: medium early potato cultivars: Barycz, Mors, Triada. The dose of cattle manure (35 t∙ha-1) was applied in autumn (before winter plowing). Fertilization with P and K amounted: 80 kg P2O5∙ha-1 and 140 kg K2O∙ha-1, respectively. Ni-trogen fertilization was used with dose 90 kg N∙ ha-1. Irrigation was conducted according to soil water potential measured by tensiometers (-0,03 MPa). The use of irrigation significantly increased the marketable tuber yield.There were no significant differences between potato yields obtained from sprinkler-irrigated plots and those from drip-irrigated plots. From among cultivars tested, Triada gave significantly higher marketable tuber yields than the other two cultivars. Cultivars were characterized by different response to irrigation. The highest increases in yields due to irrigation gave Mors, and the lowest - Barycz. The irrigation systems did not differentiate significantly the content of DM, vitamin C, reducing sugars and starch in potato tubers. Irrigation decreased the total sugar content in tubers of potato.