Vesna Židovec

MORPHOLOGICAL AND CHEMICAL PROPERTIES OF SELECTED SWEET VIOLET POPULATIONS

Sweet violet (Viola odorata L.) blooms in continental climate conditions in early spring (March-April) with delicate flowers of attractive scent because of which it is frequently gathered from its natural habitats. Differences among the populations were established according to their morphological properties of twelve populations from Križevci area. Stated information indicates that the populations gathered from meadow – habitat are shorter and have a smaller diameter than the populations gathered from the habitat in forest, whereas the population from the orchards has the highest number of leaves and flowers. Correlation analysis shows strong (P<0.01) positive connection of the root mass, leaves mass, number of leaves with the total mass of the plants, as well as connection of the plant mass with the number of flowers. Chemical analysis established agrochemical soil properties and nutrient concentrations in plants. Correlations between the examined properties of violets and soil properties indicate that the potassium concentration in the roots is in strong (P <0.01) correlation with potassium in the soil, whereas phosphorus concentration in flower is in a considerably strong (P<0.05) positive correlation with the phosphorus in the soil.

Seed quality evaluation of flower species used in dried floral arrangements

The demand for seeds of flower species used in dried floral arrangements has increased in recent years in Croatia, especially among small growers. High quality seed and plant material are extremely important for commercial floriculture. Vigour, germination potential, seed purity, and package content adjusted to package certificate in relation to the individual species, are essential features of flower production. The aim of the present study was to examine seed quality of the flower species traditionally used in dried floral arrangements, available in the Croatian market in 2011. The quality was assessed by standard ISTA seed testing methods. Nineteen samples of seeds were studied in relation to vigour and germination potential, health condition, emergence rate in containers, time of flowering, length of flowering period, authenticity of certified species, plant height, inflorescence colour, length, height and width, and the optimal drying stage for inflorescence and fruit. The study was conducted with two samples of Amaranthus caudatus, Nigella damascene and Celosia argentea var. cristata, four samples of Helichrysum bracteatum and Limonium sinuatum, one sample of Celosia argentea var. plumosa, Ammobium alatum and Gomphrena globosa, and two samples certified as dry flowers of mixed species. The poorest quality feature of all tested seeds was germination, ranging between 0 and 94%. The most frequent fungus present was Alternaria alternate. All species were correctly certified, except of one sample of Celosia argentea var. cristata and Celosia argentea var. plumose. The study suggests that the Croatian flower market should be supplied with seeds of a higher quality.

Influence of the photoperiod, daminozide application and fertilization on New England aster

The species Aster novae-angliae L., New England aster, is a short day perennial, flowering from the end of August to the end of October. It is branched out and reaches a height to 1.2 m. New England aster is grown in gardens and for cutting production. It has a flowering pot plant potential, but many of its cultivars are too tall to be grown in pots. Regulation of the day length may affect its flowering period while the application of growth retardants may regulate the shoot length and branching, as well as induce flowering in this Aster species. Growth regulators are applied in floriculture to reduce the vegetative growth of plants and to improve their aesthetic value by inducing shorter internodes (Gibson and Whipker, 2003 ; Marosz and Matysiak, 2005 ; Pinto et al. 2005 ; Pobudkiewicz and Treder, 2006). Balanced nutrition is an important tool in cultivation of agricultural plants as well as for flowering pot plants and it has to be adjusted to the plant requirements during particular development stages for which only orientational values are available for the majority of ornamental plants (Macz et al. 2001 ; Kant et al. 2005 ; Berzsenyi and Dang, 2006 ; Sharma and Sharma, 2006 ; ). The objectives of this work are to define the possibility of growing Aster novae-angliae L., ‘ September Ruby’ , as a flowering pot plant in the late summer period, determine the effect of day length and the cultivar’ s response to one time application of growth retardant, as well as topdressing with liquid mineral fertilizer on its growth and flowering.