The paper presents the results of the study on seed morphology of eight following Allium species: A. pyrenaicum Costa & Vayr., A. rotundum L., A. sphaerocephalon L., A. vineale L., A. moly L., A. karataviense Regel, A. fistulosum L. and A. nutans L. The study confirmed the substantial diversity in testa characters, especially curvature and relief of anticlinal walls as well as microsculpture of outer periclinal walls. The occurrence of raised anticlinal walls - an unusually rare feature in Allium seeds, previously observed only in a few species, was found in A. karataviense. It was also found that the testa type in A. pyrenaicum did not match the typical character combination, described before for subg. Allium sect. Allium

The aim of the study was to verify the similarity of 13 species and 5 cultivars of ornamental alliums and classify them into groups based on morphological and isozyme variation. The work embraced: Allium aflatunense, A. caeruleum, A. christophii, A. giganteum, A. karataviense, A. moly, A. nigrum, A. pyrenaicum, A. rosenbachianum, A. schubertii, A. siculum (syn. Nectaroscordum siculum), A. sphaerocephalon, A. strictum, A. stipitatum 'Album', A. 'Ivory Queen', A. 'Lucy Ball', A. 'Mont Blanc', and A. 'Purple Sensation'. Scape length, inflorescence diameter, and flowering period were recorded. Isozyme marker polymorphism was assessed by starch gel electrophoresis. Eight polymorphic isozyme systems (AAT, GPI, PGM, ALAT, ACP, DIAP, ALDO, PGD) were selected from 16 analysed in the taxa. Besides the differences between the taxa, the isozymes revealed intraspecific polymorphism in 5 systems. A total of 37 markers were obtained and used for dendrogram construction. The most similar taxa were A. karataviense with A. 'Ivory Queen', and A. karataviense with A. christophii (similarity level 0.78). A high similarity of 11 taxa belonging to one group (A. aflatunense, A. christophii, A. giganteum, A. karataviense, A. nigrum, A. schubertii, A. 'Ivory Queen', A. 'Lucy Ball', A. stipitatum 'Album', A. 'Mont Blanc', A. 'Purple Sensation') suggested that this group could be identified with the subgenus Melanocrommyum.

The study focused on the determination of phenolic acids, flavonoids and organic acids in five tulip cultivars ‘Barcelona’, ‘Columbus’, ‘Strong Gold’, ‘Super Parrot’ and ‘Tropicana’. The cultivars grown in field and in a greenhouse were exposed after cutting to different times of storage (0, 3 and 6 days). The phenolic profile contained 4-hydroxybenzoic, 2,5-dihydroxybenzoic, gallic, vanillic, syringic, salicylic, protocatechuic, trans-cinnamic, p-coumaric, caffeic, ferulic, chlorogenic and sinapic acids, as well as quercetin, rutin, luteonin, catechin and vitexin. The mean phenolic acid content was in the following order: ‘Columbus’ and ‘Tropicana’ > ’Barcelona’ > ’Strong Gold’ > ’Super Parrot’, while the levels of flavonoids were as follows: ‘Strong Gold’ > ’Barcelona’ > ’Tropicana’ > ’Columbus’ > ’Super Parrot’. The highest content of phenolic acids was confirmed for Columbus and Tropicana, while the lowest was for Super Parrot. However total phenolic content was very similar, observed between the place of cultivation, time of storage and cultivars. Malonic, succinic, acetic and citric acids were the major organic acid components in tulip petals. More organic acids (except malonic) were accumulated in tulip petals from fields than those from the greenhouse, while changes during storage were strictly correlated with cultivars.

Three hyacinth cultivars were forced under fluorescent lamps which emitted white, blue, green, yellow and red light. The plants started flowering in the first decade of February. The forcing period for two cultivars, ‘Anna Marie’ and ‘Blue Star’, was shortest under lamps emitting red light. The cultivar ‘White Pearl’ flowered equally early under lamps emitting red, white and blue light. The impact of light colour (wavelength) on the leaf greenness index (SPAD) was demonstrated. The photosynthetic activity of leaves was dependent on the cultivar. It was related both to the net rate of photosynthesis and the photosynthetic efficiency. Specific leaf area (SLA) also depended on the cultivar. The level of SLA was related to the rate of photosynthesis and its efficiency. SLA was highest in all cultivars under green and yellow colour light. The chlorophyll content in the fresh and dry weight of leaves was highest under yellow light lamps.

Hyacinths are used in flowerbed in cities. Plants are exposed to difficult urban conditions prevailing in winter, including notably to soil salinity resulting mainly from the use of sodium chloride. The aim of the study was analysed the response of Hyacinthus orientalis ‘Delft Blue’ to increased concentrations of sodium chloride in the soil. Pots with bulbs were each treated with 100 cm3 of NaCl aqueous solution at a concentration of either 10 g .dm-3 (dose level 1) or 20 g. dm-3 (dose level 2). Pots were irrigated with the NaCl aqueous solution in September or in January of the following year. After keeping the bulbs at a cool temperature for 12 weeks, the plants were grown in a greenhouse where they were assessed in terms of growth parameters and free proline content. The obtained results showed that the growth and the ornamental qualities of Hyacinthus orientalis ‘Delft Blue’ after treatment with sodium chloride were sufficient for recommending this plant for growing in flower beds exposed to salinity of 6.1-8.6 g dm-3. The leaf greenness index and proline content (in the second season) were greater and the length of forcing period was longer (in the second season), when the sodium chloride was applied to the soil on the day of planting bulbs.