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In vitro propagation is a crucial method for the mass production of high-quality plants, but the impact of microbiological interventions during ex vitro storage remains an underexplored aspect. This study aims to assess the effects of three commercial biostimulants in the form of microbiological preparations—BactoFungiStop, AzotoPower, and Guard—applied over six months through foliar sprays on the post-storage quality of Brunnera macrophylla ‘Silver Heart’, Echinacea purpurea ‘Secret Glow’, Heuchera × hybrida ‘Northern Exposure Red’, Persicaria amplecicaulis ‘JS Caliente’, and Rudbeckia × hybrida ‘Sunbeckia Sophia Yellow’ plants. The monthly application of microbiological preparations adhered to the concentrations recommended by producers. Post-storage evaluations included shoot and root parameters, leaf morphology, and chlorophyll biosynthesis. All microbiological preparations positively influenced shoot elongation in B. macrophylla ‘Silver Heart’. The microbiological treatments stimulated root development in this species, i.e., increased root length, area, volume, and the number of root forks and tips. In E. purpurea ‘Secret Glow’, all three preparations enhanced shoot length, leaf parameters, and root traits, with Guard demonstrating the highest efficacy. As for P. amplecicaulis ‘JS Caliente’, BactoFungiStop negatively affected shoot and leaf parameters but promoted root development. Heuchera × hybrida ‘Northern Exposure Red’ exhibited increased shoot and leaf dimensions with all microbiological treatments, while Rudbeckia × hybrida ‘Sunbeckia Sophia Yellow’ displayed positive responses in shoot-related traits but no impact on root development. None of the microbiological preparations influenced chlorophyll biosynthesis in any of the studied species. The results of our research can be implemented in the large-scale production of ornamental plants.

In vitro tissue culture technique, especially micropropagation, is attracting increasing attention in the production of ornamental plants. This technique will probably dominate the horticultural market in the near future. Light is one of the several factors affecting the success of in vitro plant tissue cultures. It directly affects the widely understood morphogenetic response of the explant, i.e., the ability of the explant to grow or regenerate, produce roots, etc. Lighting conditions provided during the in vitro stage may also greatly affect the plant vigor after transferring to nonsterile conditions. Moreover, the necessity of providing artificial light significantly contributes to the total cost of maintaining tissue cultures (related to energy consumption and the need to cool down the heat generated by lamps). Light quantity (intensity) and quality (spectral composition) are the two main parameters that determine its influence on in vitro cultures. This impact depends on the species and other accompanying factors. The aim of this mini-review is to summarize information on the influence of light on the morphogenetic and biochemical response of explants of some selected ornamental plant species grown under in vitro conditions.

Strawberry and wild strawberry are among the most popular horticultural crops. Due to the development of soilless cultivation systems, the whole-year production of these economically important fruit crops is achievable even in countries with temperate climate. However, the responses of strawberry (Fragaria × ananassa Duch.) and wild strawberry (Fragaria vesca L.) to microclimate conditions in greenhouse gutter cultivation in the autumn–winter season in Poland have not been yet determined. The aim of this study was to analyze the physiological, biochemical, and biometrical responses of two cultivars of strawberry ‘Ostara’ and ‘San Andreas’ and two cultivars of wild strawberry ‘Baron von Solemacher’ and ‘Regina’ grown for 20 weeks, starting from September 17th, in controlled greenhouse conditions on coconut mats in gutters in the autumn–winter season and irradiated with sodium lamps. Strawberry ‘San Andreas’ produced 30% larger leaves and almost three-fold higher fresh and dry weight of biomass than ‘Ostara’. The strawberry plants ‘San Andreas’ had a higher content (20%) of chlorophyll a and 30% of chlorophyll b than ‘Ostara’ plants. Generally, ‘San Andreas’ displayed an overall higher concentration of intercellular CO2 (about 14%) than ‘Ostara’ plants providing higher gas exchange processes. Photosynthetic rate amounted to 13.0 μmol·m−2·s−1 for ‘San Andreas’ that was almost two-fold higher than for ‘Ostara’. ‘San Andreas’ flower and fruit productions were uniform and the six-fold higher individual fruit yield proved the excellent attributes of this cultivar to the greenhouse cultivation. Even though the productivity of the two studied wild strawberry cultivars was similar, ‘Regina’ showed higher values of some parameters than ‘Baron von Solemacher’ (40% larger leaves, 25% higher photosynthetic rate, 10% higher concentration of intercellular CO2). A high nutritional value of fruits is maintained compared to traditional open-air cultivation.

The colour of florets and leaves, considerably determining the decorative nature of plants, can depend much on the conditions throughout the period of cultivation. The research analysed the occurrence of anthocyanins and carotenoids in ray florets and chlorophylls in leaves in Chrysanthemum × grandiflorum /Ramat./Kitam., ‘Baton Rouge’ grown in the glasshouse over 2010–2011. The plants were exposed only to short day induced by darkening, applying no supplementary lighting of the plants. From the ray floret tissues carotenoids were extracted using concentrated acetone and anthocyanins with 1% HCl in methanol, whereas to extract chlorophylls a and b from leaf explants, concentrated acetone was used. The samples with extracted pigments were exposed to studies applying the spectrophotometer UV-VIS 1601-PC at the wavelength corresponding to the maximum of the band of a given pigment. For carotenoids the wavelength was λ = 440 nm, for anthocyanins: λ = 530 nm, whereas for chlorophylls: λ = 645 and 663 nm. There was also defined the colour of ray florets and leaves applying the RHSCC Colour Chart [1966]. It was found that the date of plant planting, and thus their flowering, affects the concentration of pigments: anthocyanins and carotenoids in ray florets and chlorophylls in leaves and, as a result, also their colour. The highest concentration of anthocyanins was reported in the plants planted into pots on 1.12., 1.01 and on 1.07., carotenoids in the growing cycles launched on 1.11., 1.12., 1.01, 1.03, 1.07 and 1.08., while chlorophylls a and b – on 1.03.

In many ornamental plant species the light spectrum can, to a varied extent, modify growth and flowering. The literature offers information on the inhibition of growth of seedlings and cuttings of ornamental plants exposed to blue light. In this paper was investigated the effect of light of a varied spectral composition on the growth of scarlet sage (Salvia splendens) seedling. The plants were cultivated in the growth chamber at the 16-hour and 20-hour day. The following kinds of light were used: daylight – similar in its spectral composition to natural light, blue and mixed light – with the same share of daylight and blue light as well as with 75% share of blue light. The intensity of the quantum irradiance in the range PAR was the same for all the experiment combinations and it was 110 μmol · m-2 · s-1. The scarlet sage grown in mixed light with the advantage of blue light was lower than the plants produced in daylight both at the 16-hour and 20-hour day.

Cebule czterech odmian tulipanów pędzono przy sztucznym świetle, pod lampami jarzeniowymi typu TLD emitującymi światło białe, niebieskie, czerwone, żółte i zielone. Natężenie napromienienia kwantowego wynosiło 12,5 i 25 ľmolˇm -2ˇs -1. Długosć dnia odpowiednio 6 i 12 godzin. Istotny wpływ na jakość tulipanów zaobserwowano przy wysokim natężeniu napromienienia kwantowego i długim dniu. Tulipany pędzone przy świetle czerwonym miały najdłuższe pędy, o największej masie i najbardziej okazałych kwiatach. Światło niebieskie wpłynęło na poprawę sztywności łodyg i liści.

Among many challenges in chrysanthemum cross-breeding, the access to viable pollen for hybridization of cultivars distant in location and different in flowering time is required. Low pollen viability along with incompatibility are mainly responsible for low seed set in modern chrysanthemum cultivars. The aim of the study was to test various temperatures and periods of pollen storage of Chrysanthemum × morifolium in order to elaborate the method of chrysanthemum pollen preservation for cross-breeding purposes. In the first experiment, in vitro pollen germination of four cultivars was investigated following storage at 20 °C, 4 °C, −20 °C, and −80 °C, for one, four, and eight weeks. The second experiment focused on in vivo seed set after one week pollen treatment with 20 °C, 4 °C, −20 °C, and −80 °C (three pollen donor cultivars tested). Pollen in vitro germinability, as well as seed set efficiency, was generally low and cultivar dependent. Independent of the period of storage, stored pollen germinability was lower (5.30–6.63%) than fresh pollen (8.15%). Incubation of pollen in −80 °C significantly increased pollen germinability (9.80%), as well as seed set efficiency in comparison to control (19.28% and 10.21%, respectively) provided the cultivars are compatible. Among cultivars, the highest germinability of pollen was found in ‘Brda’ and ‘Donna’ (8.2% and 8.23%, respectively), while ‘Bydgoszczanka’ showed the lowest germinability (2.97%). There were also pollen genotype dependent effects in in vivo seed set efficiency, which was highest in ’Brda’ (17.57%) and much lower in ‘Jutrzenka’ and ‘Polka’ (1.34% and 0.39%, respectively), which contributed to the incompatibility of crossed cultivars rather than pollen viability.