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In the years 1993 to 1995 the effect of postfloral application of cytokinin N-6-m (hydroxybenzyl) adenosine and two nitrogen doses (40 kg/ha and 70 kg/ha in the form of calcium nitrate applied before anthesis) as exerted on the formation of yield-forming components, height of economic yield and spring wheat quality was studied in spring wheat, cv. Sandra. Six treatments were evaluated: control, control + cytokinin, 40 kg N, 40 kg N + cytokinin, 70 kg N and 70 kg N + cytokinin (Tab. II). Besides length of stem, number of tillers and dry matter, leaf area index LAI as well as tillering potential OP during the growing season were evaluated. In postfloral period, roughly six weeks after application of cytokinin, spectrophotometrical methods were used to determine activity of glutamate kinase in upper two flag leaves. Grain quality after harvest was assessed from wet gluten content (fixed on the Glutomatic device) and from the value of falling number (fixed on the device Falling Number manufactured by the Swedish company Perten). Nitrogen and cytokinin fertilization had a positive effect on the yield and quality of grain, particularly in the years 1994 and 1995. Both years differ by weather conditions (Fig. 1). Data on yield components are summed up in Tabs III to V. Out of yield-forming components (Tabs VI and VII) the number of grains per spike was the most affected, while TKW at least. Nitrogen fertilization and cytokinin application limited the reduction of tillers and reduced potential spike productivity (numbers of established spikelets and florets in spikes to actual number of grains per spike). The effect of cytokinin on glutamate kinase enzyme activity, on the value of falling number and wet gluten content (Figs 2 to 5) is evident. Treatments of 40 kg N + cytokinin and 40 kg N were manifested most. An analysis of production-ecological and yield components in different years indicates that the effect of treatment was manifested significantly particularly in less favourable years when cytokinin aided to plants to overcome the stress, e.g. in 1994 stress from drought (Tab. IV). In this weather unfavourable year the effect of treatment was most marked for the whole evaluated period. In 1993 higher dose of nitrogen decreased grain yield (Tab. III). Length of stems, number of tillers and leaf area index (which were different in wetter and warm year of 1995 and in more arid year of 1994) differed significantly along with integral characteristics, leaf area index LAI and tillering potential. In treatments 40 kg N + cytokinin increased activity of glutamate kinase (Tab. VIII) was recorded. Results presented in Figs 2 to 5 indicate some relations between glutamate kinase activity, falling number and gluten content. In addition, they also indicate significant effects of a year (weather conditions), in concrete terms - formation of progression of yield-forming components in time, and quality of production as well. Ecophysiological manifestations of growth are in congruency with literature.