Begonia (Begonia semperflorens Link et Otto) belongs to a group of annual plants that are commonly grown in city parks, mainly due to their wide colour options and adaptability to grow either in full sun or semi-shade. Good quality of begonia transplants for early planting outdoors can sometimes be hard to achieve, due to unfavourable conditions early in the season, such as low temperatures leading to insufficient nutrient uptake and plant growth. The aim of this study was to investigate the use of biostimulants for improving the conditions for raising transplants for early outdoor planting. The experiments were conducted in a non-heated glasshouse and were set up as a split plot design with treated and untreated plants in 2009, 2010 and 2011. In each year, the treatment with biostimulant Radifarm®, in a concentration of 0.25% (Valagro SpA, Italy) was applied weekly for two months, while control plants were treated with water. At the end of experiment, the following parameters were recorded: fresh and dry weights of roots and above-ground plant parts, plant height, numbers of leaves and flowers as well as concentrations of total N, P, K⁺, Ca²⁺, Mg²⁺ and free proline in roots and above-ground parts. Plants treated with biostimulant had significantly higher values for all morphological parameters investigated. At the same time, higher concentrations of K⁺ were recorded in begonia roots, while significantly higher concentrations of total N, K⁺, Ca²⁺ and Mg²⁺ were recorded in above-ground parts of biostimulant-treated plants. Biostimulant application affected proline accumulation positively.

Апстракт The aim of this study was to examine germination energy and seed germination rate of some flower species under influence of different light conditions. Seeds of Zinnia elegans Jacq., Dianthus caryophyllus L. and Callistephus chinensis (L.) Nees that were used in the research were purchased in local store. Experiment was set up in three replicates for each light treatment and each flower species. Petri dishes with seeds were placed in growth chamber under artificial white and blue light under 12hL/12hD photoperiod. Results showed no significant difference in germination energy and total germination of investigated flower species in respect of light. Zinnia seedlings were significantly longer on white light, while Dianthus seedlings were longer on blue light. Both, length and fresh weight of Callistephus seedlings were greater on white light. The absence of significant differences between measured parameters under examined light regimes suggests that germination of Zinnia, Dianthus and Callistephus is not photosensitive.

Annuals are plants that germinate, mature, bloom, set seed and die in one growing season. They are sometimes referred to as bedding plants because they provide colour and fill in garden beds. This research was conducted in the laboratory of the Department for Plant Production at the Agricultural Faculty in Osijek. The aim of this study was to determine the effect of two different temperatures (18 and 24°C) and sowing depth (2 and 3 cm) on germination of annual flower species. For the purpose of this study, two types of annual flower seeds were used, seeds of floral species Dahlia and Zinnia. Seeds were sown in trays at two different depths (2 and 3 cm) and kept in a chamber under controlled conditions at two different temperatures (18 and 24ºC). After three weeks of controlled conditions, the stems and root of young plants were measured. Root length of both flower species was significantly influenced by sowing depth and temperature (p = 0.01). Dahlia stem length was affected by sowing depth and temperature (p=0.05) while the length of Zinnia stems was not influenced by either temperature or planting depth.