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Use of Solidago rugosa ‘Fireworks’ in ground cultivation in Poland

Miron Lewandowski, Przemysław Bąbelewski ( Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland

Solidago rugosa ‘Fireworks’ is a tall perennial with rigid stems covered with hairs and wrinkled egg-shaped and lanceolate, crimson-edged or sharply toothed leaves. During flowering it is characterized by yellow effective panicles of flowers developing f rom l ate s ummer t oautumn, i.e., in Polish conditions, from September to the first decade of November. Th e ‘Fireworks’ cultivar is distinguished by small, bright yellow flowers gathered in dense, plume-like panicles at the ends of stiff, leafy stems, usually reaching 60 to 90 cm in height. Our aim was to develop a technology for the propagation and production of wrinkled goldenrod in a perennial nursery. The propagation technology was developed from herbaceous shoot cuttings made from May to June. The cuttings were 4–5 cm in size and rooted in a substrate based on high peat and sand mixed to a 1 : 0,5 ratio. The pallets with the cuttings were placed in an unheated plastic tunnel, where a high humidity of 90% was maintained throughout this phase. The tunnel was also shaded from excessive sunlight. The cuttings rooted to 80% in 40 days. Young plants were then transplanted into 2l pots in a green compost-based substrate. Observations were also made phenologically in ground cultivation, distinguishing between the vegetative and generative phases of the plants. We established that the vegetative phase ends in the second decade of July, when individual stems begin to branch into generative shoots on which inflorescences will form. The first flowers appear in the first decade of September and flowering continues until the first decade of November. Cultivation of goldenrod was then carried out in an unheated plastic tunnel, in ground beds. The fl ower ha rvest st arted in th e la st de cade of Au gust an d continued until the end of November.

Keywords: young plants, perennial, propagation


Do recently released cultivars of Ranunculus and Anemone still need vernalization?

Sara Benchaa (, Line Lapointe
Laval University, Department of Biology and the Centre for Forest Research, Quebec, Canada

It is well known that spring bulb species require a vernalization period to flower. For some species, such as Ranunculus asiaticus and Anemone coronaria, vernalization is facultative but does improve and/or hasten flowering. However, these observations are mainly based on cultivars that are no longer very popular. We thus initiated a study to identify the best combination of temperature (5, 7 and 10°C) and duration (15, 30, 45 and 60) of vernalization for different Italian cultivars of Ranunculus ('Elegance') and Anemone ('Mistral'), to optimize the timing of flowering but also total flower yield. A second series of tests with a subset of 3 vernalization treatments was run the second year. Ranunculus cultivars initiated growth during vernalization, and lower temperature did not affect their emergence rate. In contrast, the emergence of both Anemone cultivars was negatively affected by the lower vernalization temperatures. The tested vernalization temperatures did not hasten flowering in either Anemone or Ranunculus cultivars. However, a slight advancement in flowering was observed with the longer vernalization durations, albeit resulting in a reduced number of flowers and flowers of lower quality. As both species can grow under cool temperature, one can wonder if vernalization is really required prior to planting. More thorough studies are needed to improve our understanding of the environmental cues that trigger flowering in Ranunculus and especially in Anemone for which very little scientific information is currently available.

Keywords: cold exposure, flowering, geophytes, marketable flowers, Ranunculaceae, temperature


Impact of Tobacco rattle virus on the vase life of ‘Sarah Bernhardt’ peonies

Gary Chastagner ( Washington State University, WA ,USA

Tobacco rattle virus (TRV) is the most widespread virus of peonies. It can infect both herbaceous (Paeonia lactiflora) and tree (Paeonia suffruticosa) peonies. TRV symptoms most commonly consist of ringspots of alternating green and yellow concentric circles or a yellow- green mottle or mosaic. The impact of TRV on peonies is unclear. Symptoms are not expressed in flowers and observations suggest there is no marked reduction in the vigor of infected plants. To determine TRV’s impact on the postharvest quality and vase life of flowers, a display trial was conducted with ‘Sarah Bernhardt’ flower stems harvested from PCR-tested TRV+ and TRV− plants. Stems were placed in jars containing water and displayed in a lighted display room maintained at 20°C. A total of seven pairs of jars containing either three TRV+ or three TRV− stems were included in this trial. Changes in the condition of the flowers were monitored daily. The diameter of the open flowers was measured on day 5, and the vase life was based on the number of days before flower petals exhibited any symptoms of wilting and/or loss of petals when the flower was gently shaken. Statistically, there was no difference in the flower size or vase life of the flowers from TRV+ and TRV− plants. All the flower buds opened within the first day and the average size of the TRV+ and TRV− flowers was 13.2 cm and 13.0 cm, respectively. The TRV+ and TRV− flowers had an average vase life of 6.8 and 7.0 days, respectively. While no difference in flower quality and vase life was observed in this trial, additional studies are needed to determine if TRV infections have any impact on flowers from other cultivars. Studies are also needed to determine, what if any impact TRV has on the vigor and productivity of peonies.

Keywords: herbaceous peony, Paeonia lactiflora, Paeonia suffruticosa, tree peony


Changes in biomass partitioning based on phenological observation in Lilium hybrids

Hoon Choi (, Nam Hyun Im, Hyo Beom Lee Seoul National University, Seoul, Korea

Phenology is an indicator of life development in biological events through cyclical or seasonal changes. Biomass partitioning is important for characterizing plant developmental processes and an indicator of crop growth status. This study was conducted to determine changes in biomass partitioning across developmental stages in Lilium hybrids. The developmental stages were defined by phenological observation based on the BBCH-scale in two Lilium cultivars. Growing degree days (GDD) in developmental stages were calculated for each cultivar. Fresh and dry weights of bulblets, bulb roots, stem roots, stem, leaves, and floral organs were measured and applied to the phenological scale. Leaf chlorophyll content (SPAD value), the number of leaves, and leaf area were also monitored during the growing period. The total biomass continued to increase until leaf senescence, although it slightly decreased at the shoot emergence stage. Stem roots were developed at the visible flower bud stage. However, the bulb biomass gradually decreased from shoot emergence to full blooming regardless of cultivars and then started to increase from 50% flower opening stage. Leaf numbers and area increased during the leaf development stage and maintained from the visible flower bud stage to leaf senescence, and a similar trend was observed in the stem and leaf biomasses. SPAD value began to decrease at the end of the flowering stage, and this change allowed the identification of the shift in the developmental stage towards senescence. These results demonstrated biomass allocation change in accordance with developmental stages. The findings will be applied to developing a crop growth model in Lilium hybrids.

Keywords: biomass partitioning, developmental stage, GDD, Lilium, phenology


Flower bulbs in Mexico in relation to world production

Amando Espinosa-Flores (, María de los Ángeles Rodríguez Elizalde, Jose Merced Mejía-Muñoz

Chapingo Autonomous University, Mexico Texcoco, Mexico

The international trade of flowers is a very dynamic activity of the world economy, which generates more than 35,000 million dollars, with annual growth rates of 6%. Within this sector, the world production and trade of flower bulbs is also important with more tan 31,000 hectares of which the Netherlands represents 65% (20,150 in 2008 and 21,400 in season 2020/21) of the world production with 10,000 million bulbs that include tulip, lily, hyacinth and daffodil species. Regarding Mexico, 5,168 hectares of bulb flowers are cultivated with a production value of 152 million dollars, Gladiola being the one that represents 87% of its surface, lilium, tulip and dahlia cover only 13%. The states of Mexico and Puebla represent 63.3% of its total surface. While Mexico City, Morelos, Michoacán, Guerrero, Veracruz and Oaxaca cover 36.7%. Mexico depends on bulbs from the Netherlands to obtain quality flowers. 100% of the producers import lilies and tulips. And in gladiola 72.3%. Bulbs are grown in 145 countries, with the Netherlands, Canada, USA, Belgium, Israel, England, New Zealand, Germany and Chile being the main exporters. In Mexico, for 20 years, international participation in the flower and vegetative material markets has reached only 3% and during this period the trade balance of all flower products in some years has shown a deficit. The free trade agreements TLC (1994) and T-MEC (2020) has had little impact on the flower sector, since of the 3,300 producers of bulb flowers, only 3.7% are dedicated to exporting to the United States and Canada. Given this scenario, the production of quality vegetative material, the search for international markets, post-harvest handling and packaging of products must be improved, as Colombia, Chile, the Netherlands, Israel and China have done.

Keywords: countries, technology change, trade agreements


The effect of varying greenhouse conditions for forcing Cymbidium orchids growth in a tropical climate region

Kanokwan Panjama, Soraya Ruamrungsri, Chaiartid Inkham ( Chiang Mai University, Chiang Mai, Thailand

Cymbidium is a popular orchid in the world market. The demand in the Flora Holland auction was approximately 22.8 million stems in 2015 (AIPH, 2016). Thailand imported Cymbidium from China because the production area is too limited to only in highlands at an altitude of 1,000 meters above sea level. Therefore, growing Cymbidium in a controlled environmental greenhouse was the way to solve the problem. This research aimed to study the effect of greenhouse temperatures on controlling the flowering of Cymbidium. Three years, Cymbidium ‘Fuku Musume’ was selected and grown in a 50% shading greenhouse (with avg. light intensity of 260 μmol m−2 s−1, relative humidity (RH) of 70%, and temperature 26–30°C) for 3 months before moving to different greenhouse condition treatments. The experimental design was completely randomized design (CRD) with 3 treatments, 8 replications (pots) i.e., T1) plants were continuously grown in 50% shading greenhouse for 5 months, T2) plants were moved to evaporative greenhouse (with avg. 200 μmol m−2 s−1 light intensity, 85% RH and temperature being 20–25°C for 5 months and T3) plants were moved to glasshouse (with avg. 100 μmol m−2 s−1 light intensity, 80% RH and temperature being 18–20°C). Liquid fertilizer was supplied every week with 500 ml/pot. The number of leaves per plant and leaf length were measured monthly for 5 months. Flowering percentage, flower quality, leaf color intensity, photosynthesis rate, transpiration rate, and stomatal conductance were recorded. The results found that different greenhouse conditions did not affect leaf length. Ho wever, growing Cymbidium in the glasshouse (T3) increased leaf color intensity. The flowering percentage was the highest, about 87% in T3, and flower abortion was found in T1 and T2. Photosynthetic rates of Cymbidium reached a maximum value at 10:00 a.m. Forcing Cymbidium by growing in a 50% shading greenhouse for 3 months before transplanting to a glasshouse could stimulate flowering within 144 days with 2 stems/pot with 12.4 florets/ stem, 64.9 cm of inflorescence length.

Keywords: agricultural management, control flowering, crop improvement, crop management, cymbidium, growth and development, temperature


Longevity of Lachenalia cut flowers
Anna Kapczyńska (, Małgorzata Maślanka, Justyna Mazur

University of Agriculture in Krakow, Krakow, Poland

Lachenalia (Asparagaceae) is a bulbous gephyte endemic to winter-rainfall region of southern Africa. A breeding program resulted in obtaining extremely attractive cultivars with high potential for commercialization on the international market of cut and potted flowers. In this study, Lachenalia cultivars, ‘Ronina’ (yellow flowers) and ‘Rupert’ (lilac-purple flowers), were evaluated for a vase life of inflorescences. Stems were cut from plants forced in a greenhouse and then placed in glass vases filled with distilled water. The first flowers dried on the inflorescence stem after 12 or 10 days in ‘Ronina’ and ‘Rupert’, respectively. The tested genotypes turned out to be very long-lasting. After 24 days of experiment in ‘Ronina’ and 20 days in ‘Rupert’, half of the flowers in the inflorescence were still open and kept the right turgor and color. On the 28th and 24th day in ‘Ronina’ and ‘Rupert’, respectively, more than 20% of flowers in inflorescences were still decorative. Finally, all flowers (or unopened buds) withered on day 30 in ‘Ronina’ and on day 26 in ‘Rupert’. All the buds of ‘Ronina’ cultivar developed into mature flowers but in case of ‘Rupert’, more than 30% of the green buds did not open at all. The obtained results indicate that the tested cultivars are characterized by slow-to-age and long-lasting flowers, which even during aging retain their decorativeness, slightly changing color.

Keywords: African geophyte, Cape hyacinth, ‘Ronina’, ‘Rupert’, vase life


Breeding of Rudbeckia hirta L. using mutation techniques

Szilvia Kisvarga1 (, Katalin Horotán2, Dóra Hamar-Farkas1,

Gabor Boronkay1, Jana Táborská2, László Orlóci1

1Hungarian University of Agriculture and Life Sciences, Budapest, Hungary 2Eszterházy Károly Catholic University, Eger, Hungary

The role of mutation breeding in ornamental plant breeding has increased significantly in recent decades. Within mutation breeding, gamma radiation is a very effective method, as phenotypically different variants can be created relatively easily. And this will be very necessary in the future, as the trade in ornamental plants constantly requires new cultivars, and in addition, due to climate change, cultivars resistant to abiotic stress are becoming more and more important. Rudbeckia hirta L. has long been a very popular species in urban landscaping. Rudbeckia hirta is officially an annual species, but it can be grown as a short-lived perennial in several countries – mainly due to climate change since increasing global warming. The famous Hungarian Rudbeckia hirta cultivars create a very rich gene bank for breeding. The plants created during different doses of gamma radiation can be suitable as the genetic basis of new cultivars. In our measurements, we used different doses of gamma radiation, and we subjected the variants to morphological, histological tests. The aim of our measurements is to breed new cultivars for public areas that can withstand the current climate.

Keywords: annual, climate, cultivar, gamma, novelty, ornamental, perennial


Use of miscanthus-based substrate in nursery production of Rudbeckia fulgida ‘Goldsturm’

Miron Lewandowski (, Przemysław Bąbelewski Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland

Rudbeckia fulgida ‘Goldsturm’ is a medium-height perennial with an erect, straight stem covered with fine hairs. Clasping leaves wrap around the stem, the lower leaves are characterized by a broad ovate shape with a sharp tip and serration, while the upper leaves are lanceolate in shape and are entire-edged, also covered with rough hairs. The outer lingual flowers are yellow, while the inner tubular flowers are dark brown. The bottom of the basket is strongly convex. Flowering in the climatic conditions of Poland takes place in summer and early autumn – from July to mid-October. The plant reaches a height of 40–60 cm. The purpose of the study was to examine the suitability of fresh miscanthus straw in Rudbeckia nursery production used both separately and in substrate mixtures. We considered five types of substrate mixtures – mixtures containing 100% peat, 100% miscanthus straw, a mixture of 50% each of straw and peat, and a mixture of 70% peat and 30% miscanthus and 70% miscanthus and 30% peat were used. Each mixture was treated with three fertilizer mixtures: Basacote (3 g·dm−3, premixed with substrate), Basacote (3 g·dm−3, premixed with substrate) + YaraMila Complex (top dressing, three times during vegetation period at a dose of 1 g·dm−3) and YaraMila Complex (3 g·dm−3, premixed with substrate and top dressing, three times during vegetation period at a dose of 1 g·dm−3). The tests were performed in an outdoor nursery – rooted plant cuttings were transplanted into 3L pots with the appropriate substrate mix and placed on black nursery fabric with sprinkling irrigation. For each fertilizer mixture, plants had greater height and diameter in the substrate that was 100% peat, but greater leaf size and area in the mixture of 50% peat and miscanthus. Both average plant height and inflorescence diameter were lowest for substrates predominatly made of miscanthus straw. The average number of leaves per plant was smallest for substrates based mostly on miscanthus.

Keywords: grow, fertilizer, perennial


Phenotypic and cytogenetic characteristics study of winter hardy woody and herbaceous Hibiscus

Ki-Byung Lim1 (, Deen Mohammad Deepo1, Yun-Jae Ahn1, Yoon-Jung Hwang2

1Kyungpook National University, Daegu, Korea 2Sahmyook University, Seoul, Korea

Modern plant breeding requires knowing phenotypic features and information on cytogenetic traits prior to the breeding program. The purpose of this study was to determine phenotypic and cytogenetic characteristics of winter hardy woody and herbaceous Hibiscus. Four cultivars from woody Hibiscus syriacus and two cultivars from herbaceous Hibiscus moscheutos were used in this experiment. Among the study materials, H. moscheutos ‘Carousel Jolly Heart’ had the largest flower diameter (16.70 cm), with a crimson color, whereas H. syriacus ‘Yaum,’ had the smallest flower size (9.60 cm), with light pink color. The leaves of H. syriacus ‘Yaum’ and ‘Freedom’ were lanceolate and the leaves of H. moscheutos ‘Carousel Jolly Heart’were elliptical. H. syriacus ‘Sukim’, ‘Wasung’ and H. moscheutos ‘Carousel Pink Passion’ had palmate leaves. Chromosomes’ number reported in H. moscheutos was 38 while H. syriacus ‘Sukim’, ‘Freedom’, ‘Wasung’ and‘Yuam’ possessed 84, 84, 82, and 86 chromosomes sequentially. According to fluorescence in situ hybridization (FISH) results, two 5S rDNA loci were detected in all cultivars of H. syriacus and H. moscheutos. While four 18S rDNA loci were detected in H. syriacus, H. moscheutos ‘Carousel Jolly Heart’ and ‘Carousel Pink Passion’. Flow cytometry results showed, 2C-DNA contents of H. syriacus ‘Sukim’, ‘Freedom’, ‘Wasung’ and ‘Yaum’ had 4.18, 4.27, 4.17, 4.08 pg respectively whereas ‘Carousel Jolly Heart’, and ‘Carousel Pink Passion’ had 2.06 pg and 2.05 pg correspondingly. These findings will help with the in-depth cytogenetic investigation of H. syriacus and H. moscheutos, which will assist with plant breeding in this genus.

Keywords: 5S rDNA, 18S rDNA, cytogenetics, fluorescence in situ hybridization, phenotype


Effect of aeration and volume of medium on biomass growth and shoot propagation in bioreactor cultures of Heuchera, Hosta and Echinacea

Małgorzata Malik1, Krystyna Norwa2, Piotr Norwa2, Jelena Akik2, Dorota Majos2, Eleonora Gabryszewska2, Monika Cioć1 (, Bożena Pawłowska1

1University of Agriculture in Krakow, Krakow, Poland 2Norwa Plants Tissue Culture Laboratory, Piaseczno, Poland

Production efficiency in bioreactors depends primarily on the method and degree of aeration of the culture immersed in the medium, conditioned by the construction of the vessel, the way the system works, and the production technology. A bioreactor SetisTM was selected for the experiment, which makes it possible not only to set the frequency of culture immersion with the medium but also the frequency of aeration of the culture and the volume of the medium. The aim of the experiment was to establish the effect of aeration (20 sec/120 min or 60 sec/120 min) and volume of medium (1200 or 1800 mL in a six-liter culture vessel, with a culture density of 10 explants per 200 mL of medium) on the growth of six Heuchera, Hosta, and Echinacea genotypes. For each genotype, predetermined optimal compositions of propagation media as well as frequencies of immersion were used. After four weeks, the indexes of shoot multiplication and biomass growth were determined. Both indexes were genotype-dependent. The multiplication of shoots can be intensified by increasing the volume of the medium in the case of both Heuchera cultivars and one of the Echinacea cultivars. The growth of Heuchera biomass is affected by the volume of the medium and aeration. Increasing the media volume and extending the aeration time (up to 60 sec) is conducive to Heuchera biomass growth. Extending the aeration time resulted in a decrease in the number of shoots obtained in one of the Hosta cultivars. Depending on the levels of the aeration time and volume of medium, the shoot multiplication and biomass growth indexes were, respectively, were as follows: 4.9–16.4 and 5.6–19.2 in Heuchera, 2.4–5.2 and 17.9–39.9 in Echinacea, 3.2–5.8 and 4.5–10.6 in Hosta.

The research was financed by the National Centre for Research and Development (NCBR) under the ‘Konkurs 3/1.1.1/2020 – Szybka ścieżka dla Mazowsza’ (POIR.01.01.01-00- 0178/20).

Keywords: in vitro, perennials, Setis, temporary immersion system


Effect of fluridone on the growth and some physiological features in leaves and roots of uncooled Muscari armeniacum bulbs

Agnieszka Marasek-Ciołakowska1 (, Marian Saniewski1, Justyna Góraj-Koniarska1, Joanna Mitrus2, Marcin Horbowicz3

1The National Institute of Horticultural Research, Skierniewice, Poland 2Siedlce University, Siedlce, Poland
3University of Warmia and Mazury in Olsztyn, Olsztyn, Poland

The herbicide fluridone (1-methyl-3-phenyl-5-[3-trifluoromethyl(phenyl)]-4(1H)- pyridinone) disrupts the carotenoid biosynthetic pathway in plants. Fluridone inhibits the activity of phytoene desaturase, the enzyme responsible for converting phytoene to phytofluene, and indirectly inhibits the biosynthesis of plant hormones such as abscisic acid (ABA) and strigolactones. Fluridone also affects many physiological and biochemical processes related to plant growth and development. For our experiments with fluridone, uncooled Muscari armeniacum bulbs with fully differentiated primary roots were used. Continuous soaking of bulbs with fluridone at concentrations of 5 and 10 mg/l significantly inhibited root growth and caused the appearance of lateral roots. Besides, in the leaves of growing and treated with fluridone M. armeniacum plants, chlorophyll was degraded and red color appeared on them. Histological analysis showed that in Muscari leaves, anthocyanins are found only in the parenchyma, but not in the epidermis. Chlorophyll, carotenoids and anthocyanin analyses were carried out in the leaves of treated and untreated M. armeniacum plants. The results presented will be discussed with the results of available studies on the physiological and biochemical effects of fluridone on other plant species. It is worth mentioning that fluridone is considered as a new anti-inflammatory drug.

Keywords: anthocyanins, carotenoids, chlorophyll, fluridone, Muscari armeniacum


Effect of biostimulant Kelpak SL on growth, flowering and tuber yield of Dahlia

Barbara Marcinek ( University of Life Sciences in Lublin, Lublin, Poland

Dahlias (Dahlia hybrida) are a valuable group of seasonal plants for growing in home gardens, landscaped areas, and as cut flowers. The advantages of the plants include a huge selection of cultivars, with varied size and shape of inflorescences, rich colors, and low cost of cultivation. The main problem is a low durability of cut flowers and large differences in yield of cultivated varieties. Two cultivars were used in the study: ‘Franz Kafka’ and ‘White Aster’ from the pompon group. Dahlias were grown from cuttings, obtained from mother carpels. The seedlings were planted in the open ground on June the 1st. Spraying with Kelpak SL biostimulant based on seaweed (Ecklonia maxima) at concentrations of 0.5%, 1.0% and 1.5% was carried out twice: 30 and 60 days after planting. During the growing season, plant height was measured twice, 3 weeks after the application of sprays. Inflorescence shoots were cut successively from August 23 till the end of September. In the case of both varieties cut shoots had several flowers, single inflorescences were not cut due to too short peduncles. The length and weight of inflorescence shoots, as well as peduncle length and flower diameter were analyzed. The yield of inflorescence shoots and the number of flowers were determined. The root carpels were dug out on October the 30th, and the weight of root tubers, number and length of tuberous roots were determined. Plant height after applying Kelpak SL as a spray at a concentration of 1.0–1.5% was higher than in control plants by 18–20% in ‘Franz Kafka’ and by 15–35% in ‘White Aster’. Kelpak SL stimulated flowering of dahlias. The cultivar ‘Franz Kafka’ had 26% more inflorescence shoots and 51% more flowers were obtained. In ‘White Aster’ dahlias, the increases were, respectively: 20% and 34%. Kelpak SL applied at a concentration of 1.5% had a beneficial effect on shoot length and weight. There was no effect of the applied treatments on inflorescence diameter and inflorescence peduncle length. The biostimulant applied by foliar spray at a concentration of 1.5% favorably affected the weight of root stalks in the cultivar ‘Franz Kafka’. The cultivar ‘White Aster’ treated with the biostimulant at a concentration of 0.5–1.5% formed longer root tubers, but no differences in the number and weight of root carpels were noted. The preparation had a beneficial effect on flower filling, shoot stiffness and leaf greening.

Keywords: foliar spray, quality of cut flowers, seedlings, yield of cut flowers, yield of root tubers


Effect of gibberellic acid on growth, flowering and tuber yield of Dahlia

Barbara Marcinek (, Marzena Parzymies University of Life Sciences in Lublin, Lublin, Poland

Dahlias (Dahlia hybrida) are popular cut flowers in summer and autumn. Their beautiful, colorful flowers are used for wedding and occasional bouquets and for interior decorations. Due to the low vase life of the flowers, they are not exported and their production is mainly local. The advantages of growing dahlias are low costs, low requirements of plants and a wide selection of varieties. The problem in cultivation is the large variation in the yield of cultivars, as well as the quality of the inflorescence stems. For cut flower cultivation, root tuber consisting of several tuberous roots are mainly used. In the present study, the possibility of growing dahlias for cut flower from stem cuttings was analyzed. Two cultivars from pompon flowers group: ‘Franz Kafka’ and ‘White Aster’, were used for experiments. The cuttings were rooted in March in the greenhouse and planted in the ground on June the 1st. Gibberellic acid GA3 and GA4+7 (Gibb Plus 11SL formulation 75% GA4 and 25% GA7) were used for spraying at concentrations of 50, 100 and 150 mg·dm−3. Sprays were made twice: 30 and 60 days after planting. During the growing season, plant height was measured twice, 3 weeks after the sprays were applied. The inflorescence shoots were cut successively from August 23 to the end of September. In both varieties, the cut shoots had several flowers each (twig cultivars). The length and weight of inflorescence shoots, as well as the length of the peduncle and the diameter of the flowers were measured. The yield of inflorescence shoots and the number of flowers were determined. Tuber carpels were dug out on October the 30th, the weight of root tubers, the number and length of tuberous roots were determined. GA3 and GA4+7 applied at a concentration of 100–150 mg·dm−3 significantly increased plant height after a single spray application. After the second application, on already proliferated dahlias, gibberellic acid showed a strong stimulating effect even at a low concentration of 50 mg·dm−3. The response of cultivars to gibberellic acid varied. In the case of cultivar ‘Franz Kafka’, GA3 at 100– 150 mg·dm−3 and GA4+7 at 150 mg·dm−3 increased the number of inflorescence shoots by 13– 20% and 39%, respectively, and the number of inflorescences per plant on average by 10–21%. The cultivar ‘White Aster’ produced the most shoots and flowers (60 to 100% more) after application of GA3 and GA4+7 at a concentration of 150 mg·dm−3. Both cultivars treated with gibberellic acid produced shoots with lower fresh weight and smaller flower diameter. GA3 had a stronger negative effect on these traits. Inflorescence shoots were characterized by lower stiffness compared to control plants. There was no effect of gibberellic acid on the yield of tubers and their biometric traits.

Keywords: dahlia, cut flowers, gibberellin, flower quality, foliar spaying, yield of cut flowers, yield of root tubers


Micropropagation, acclimatization and in vitro mutation breeding of ornamental perennial Veronica hybrid

Natalia Miler1 (, Aleksander Michalik2, Janusz Winiecki3, Natalia Wiśniewska3, Anna Zielińska1, Sara Michas1, Karolina Wajer1, Mariola Streich1

1Bydgoszcz University of Science and Technology, Bydgoszcz, Poland 2Vitroflora Producer Group LTD , Trzesacz, Poland
3Nicolas Copernicus University in Torun, Torun, Poland

Perennial hybrids obtained from Veronica spicata and V. longifolia cross-breeding have been recently gaining the interest of gardeners and landscapers for their exceptional ornamental candle-shaped inflorescences, long flowering period and a palette of flower colors: from dark violet, purple and pink hues to white. The aim of the experiment was to elaborate the protocol for micropropagation and mutation breeding of Veronica hybrids.Three genotypes were selected for experiments, namely A,B and C, differing in colour. As starting explants third to fifth nodal segments of stems were excised from outdoor pot cultivated mother plants. The e fficient disinfection (70% of sterile explants) was conducted with 1% sodium hypochloride with a drop of thymus oil for 10 min. For further multiplication stage the genotype A was chosen, since the other formed flowers in vitro at establishment stage. Clonal multiplication was conducted with single-node explants cultured on MS based medium supplemented with 0–0.3 mg/L of kinetin. The highest propagation rate was observed on medium with the highest kinetin concentration. Leaves and internodes segments were tested in terms of adventitious shoots formation for breeding purposes. Internodes formed more shoots than leaves, for both types of explants the best results were obtained on medium supplemented with 0.6 mg/L BAP and 2 mg/L IAA. Rooting of shoot tips with five fully developed leaves was performed on half- strength MS medium supplemented with 2.0 mg/L IAA. Root primordia of 1 mm length appeared after 11 days. The highest quality of acclimatized microshoots was observed with the application of BaktoTarcza (BioLider, Poland) microbial additive to substarte.For breeding experiments, leaves and internodes in vitro were irradiated with high-energy photons followed by adventitious regeneration in vitro. The irradiation was performed with VitalBeam 2.7 (Palo Alto, USA) at beam energy of 600 MV, total delivered doses were 5, 10 and 15 Gy, the dose rate was 4.95 Gy/min. The regeneration efficiency was affected by the dose delivered and explant type: the lowest number of adventitious shoots were formed on leaves irradiated with 15 Gy.

Keywords: micropropagation, mutation breeding, Veronica spicata, Veronica longifolia


Bioactive compounds analysis in inflorescences of Polish winterhardy hybrids of chrysanthemum: the preliminary evaluation of possible herbal applications

Natalia Miler1 (, Anita Woźny1, Maciej Balcerek2, Wiktoria Łączna1

1Bydgoszcz University of Science and Technology, Bydgoszcz, Poland 2Nicolas Copernicus University in Torun, Torun, Poland

Chrysanthemum are not only the topmost ornamental plants worldwide but they also play an important role in Asian traditional medicine as well as cuisine. In Europe chrysanthemums are mainly greenhouse produced for ornamental purposes, both as pot and cut flowers, the small share of production is dedicated for landscape application. Herbal uses of chrysanthemums are hardly known in European countries, therefore cultivars showing the potential for herbal application that can be field cultivated in Europe are missing. The aim of our study was to take an attempt of evaluation of Polish winterhardy chrysanthemum hybrids in terms of bioactive compounds content. Nine genotypes were selected from the group of winterhardy Gardy hybrids (Ch. morifolium × Ch. rubellum) aimed at the flowering earliness. The white, full type chrysanthemum purchased from commercial grower as traditional Chinese tea cultivar served as reference plant. The inflorescences at full flowering were collected in September and they were submitted to bioflavonoids and carotenoids estimation with spectrophotometric method following the extraction. Three genotypes, namely CD4, CD26 i CD31, showed significantly higher bioflavonoids content than reference cultivar. Since these genotypes present also valuable appearance, hardiness and earliness of flowering, they can be valuable components of herbal gardens with double application: ornamental and edible.These preliminary studies will be continued in terms of more detailed specification of bioactive compounds content in Polish hardy chrysanthemums and they potential uses in herbal medicine.

Keywords: bioflavonoids content, Chrysanthemum rubellum × Ch. morifolium


Controlling plant height in three oxalis (Oxalis spp.) using plant growth regulators

Chad Miller ( Colorado State University, CO, USA

The shamrock plant (O. regnellii), purple shamrock (O. triangularis) and iron cross shamrock (O. deppeii) are specialty potted floriculture bulb crops, grown for their clover-like leaves and flowers and are commonly produced around the St. Patrick’s Day holiday. Applications of plant growth regulators (PGRs) (anti-gibberellins) can be applied to many different greenhouse grown potted plants during production to assist in controlling plant height in order to achieve quality, marketable plants. The objective of this research was to quantify the efficacy of different commercial PGRs on plant growth and development in pre- plant rhizome soaks and substrate drenches of different oxalis species. In experiment one, O. regnellii, O. triangularis, and O. deppei rhizomes were soaked before planting in different PGR solutions of water (control), flurprimidol (50, 100, and 200 ppm), paclobutrazol (50, 100, and 200 ppm), uniconazole (5, 10, and 20 ppm), or ethephon (100, 250, and 500 ppm). In a second experiment, O. regnellii and O. deppei plants were treated with media drenches of the same PGRs; water (control), flurprimidol (0.25, 0.50, and 1.0 mg a.i.), paclobutrazol (0.125, 0.250, and 0.375 mg), uniconazole (0.025, 0.05, and 0.1 mg), or ethephon (100, 250, and 500 ppm). Our results showed all concentrations of paclobutrazol, flurprimidol, and uniconazole pre-plant rhizome soak treatments, for all three species, significantly reduced plant heights, between 54% and 98% compared to control plant heights. Ethephon pre-plant treatments reduced plant heights for O. regnellii, while they increased O. deppeii plant heights up to 33%. Similar results were found in media drenches; compared to control plants, plant heights were reduced between 24% and 77% for paclobutrazol, flurprimidol, and uniconazole treatments in both species. Ethephon 100 and 250 ppm treatments increased plant heights, while 500 ppm treatments reduced plant heights.

Keywords: floriculture, greenhouse production, horticulture, media drench, potted plants, rhizome


Performance of Achimenes in landscape trials
Chad Miller1 (, Abby Pace2, Charia Hishaw3, Tara Conroy1,

Kimberly Williams4, Cheryl Boyer4, David Staats1

1Colorado State University, Fort Collins, CO, USA 2Oklahoma State University, Manhattan, KS, USA 3Langston University, Langston, OK, USA4Kansas State University, Manhattan, KS, USA

Achimenes are a member of the Gesneriaceae and a geophytic herbaceous plant, arising from scaly rhizomes. The genus has typically been produced for use as a potted flowering plant and used in mixed containers and hanging baskets. Plants bloom continuously throughout the summer in a wide spectrum of colors; reds, yellows, pinks, blues, violets, and whites, in single and double forms. However, limited cultural information exists on landscape use of Achimenes. The objective of this study was to assess plant performance of several Achimenes cultivars in different landscape microclimates at two different geographic locations in public garden spaces at Kansas State University [(KSU) Manhattan, KS USA] and Colorado State University [(CSU) Fort Collins, CO USA]. Plants were evaluated in two landscape situations: in the ground and in large planters. Plants were evaluated in sun and part-shade to shade conditions. Growth parameters measured included plant height and width, ratings (scale of 0 to 6) for water spotting, sunscald, and overall plant quality were recorded weekly for 6 weeks. At KSU, ‘Purple Prince’ achimenes were planted into the landscape on 21 Jun and data collection ended on 2 Aug 2023. At CSU, several cultivars were planted in the landscape on 12 Jul and data collected ended on 24 Aug 2023. ‘Pink Clouds’ was trialed in both containers and in the ground soil. ‘Purple Prince’ performed better in the soilless substrate of containers compared to the soil. Similarly, ‘Pink Clouds’ performed slightly better in soilless substrate plantings. Plant quality for ‘Purple Prince’ deteriorated rapidly in high light intensity environments, and sun scald ratings were ~two ratings units worse in sun compared to shade each week. Water spotting from cold irrigation water, which causes irreversible foliar damage, limits overhead irrigation in the landscape. ‘Pink Clouds’ was more resistant to foliage damage.

Keywords: floriculture, gesneriad, horticulture, hot water plant, monkey-faced pansy, nut orchid


Effects of exogenous plant growth regulators on rhizome coloration in red rhizome lotus

Rin Miura1 (, Keita Tomiyoshi1, Maiko Kurisaki1, Sae Fuji- mori1, Ikuo Miyajima1, Jun-Ichiro Masuda2, Yuki Mizunoe1, Sho Hirata1, Yukio Ozaki1

1Kyushu University, Fukuoka, Japan 2University of Miyazaki, Miyazaki, Japan

Lotus (Nelumbo nucifera Gaertn.) is an aquatic plant cultivated for edible as well as ornamental uses in Japan since ancient times. Of these, ‘Tomohiro’ is a remarkable cultivar because of its reddish rhizome coloration. The flower color of the cultivar is deep-red, darker than other red flower cultivars, so that it is expected to have high commercial potential. Rhizomes of the cultivar are not colored in the early stages of growth, and rhizome coloration develops as growth progresses. In common white rhizome lotus, it was reported that rhizome growth can be controlled by plant growth regulators. Rhizome elongation was promoted by the treatment with gibberellin, and rhizome hypertrophy was observed under the treatments with the gibberellin biosynthesis inhibitors and abscisic acid (ABA). However, the effects of plant growth regulators on rhizome growth and flower coloration in red rhizome lotus have been unknown. In this study, the effects of ABA and ethephon treatments on rhizome growth and coloration in red rhizome lotus ‘Tomohiro’ were investigated. There was no flowering in ‘Tomohiro’ in each treatment because of the limited cultivation area and genetic backgroung, so that effects of exogenous plant growth regulators on flowering was not elucidated. The results showed that 25 mg·L−1 ABA treatment enhanced red coloration of rhizome in both epidermal and internal parts, especially, at the distal internodes, whereas 10 mg·L−1 ethephon treatment delayed coloration in both parts of the rhizome. The results indicate that 25 mg·L−1 ABA treatment is effective for promoting red coloration in red rhizome lotus.

Keywords: abscisic acid, anthocyanin, gibberellin biosynthesis inhibitor, Nelumbo nucifera


Dynamic climate changes determine the new directions in ornamental perennials introduction in Poland

Marta Joanna Monder (, Andrzej Pacholczak
Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland

The consequence of rapid climatic changes in last dozens of years are rising average air temperature and prolonged the growing season. The dormancy period, plant phenology, the life cycle of animals are undergoing significant changes and leading to the necessity of changing the existing preferences in the selection of ornamental plants for cultivation. The extreme weather events, e.g., record-breaking heat waves, drenching rains, severe floods, years-long droughts, extreme wildfires, are becoming a “new norm” and intensifying a risk of plant production. Simultaneously, the climate change encourage plant invasions and spreading of invasive species regards to the geographic areas and various communities. The problems concern also ornamental plants, which determine the well-being of human especially in the anthropogenic environment of urbanized areas. The properly new ornamentals should be considered to the Green and Blue City ideas implementation in urbanized areas with a high degree of anthropopression and to the gardens with extensive methods of cultivation. The perennials create a favorable conditions for trees, pollinators and little animals life. In this work, we propose the rarely or unknown in cultivation species for north-east Europe, which currently occupy the areas with high biodiversity value, including biodiversity hotspots: (i) Mediterranean coasts and islands; (ii) Turkey, Iran; (iii) Caucasus; (iv) Altai; (v) Middle Asian mountains. The some of them are endemic and their cultivation may contribute to protect them. Exploration, especially of areas identified as biodiversity hotspots, can yield valuable taxa of ornamentals. There are, e.g. Anchusa sp., Anemone sp., Anthericum liliago, Asphodeline lutea, Catananche caerulea, Corydalis caucasica, Crepis rubra, Digitalis lanata, Echium sp., Galega officinalis, Onosma sp., Vincetoxicum arundinaria. However, their possibility of cultivation and impact on biodiversity should be assessed before they will be introduced to the production, bearing in mind that horticulture is an important source of invasive alien species.

Keywords: biodiversity, coastal flora, endemic plants, invasive species, mountain flora, water fluctuations


Hotspot geophytes may support biodiversity in green areas in Poland under changing climate conditions

Marta Joanna Monder (, Andrzej Pacholczak Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland

The droughts, heat waves and floods are considered to be the most destructive natural hazards connected with the climate changes in temperate zone. The changes in bud dormancy, plant phenology and simultaneously the life cycle of pollinators and herbivores are predicted. In the consequence, the numerous native species will no longer be able to develop in their current habitats and similarly the cultivated ornamental plants will not perform their function, due to lack of tolerance to new environmental conditions. Moreover, the currently tendences to the widening and rewilding the areas in cities and gardens could be difficult to realize in the anthropogenic environment, where the specific adaptation is needed. In conclusion, the geophytes presenting low level of invasiveness should be considered because of their ecological value for widening biodiversity of communities due to mostly early-spring or autumn flowering. The specific developmental mechanisms and whole-plant morphological diversity of geophytes present a growth model enabling adaptation to more seasonal climates and changing water and nutrients resources. Moreover, the higher tolerance to the salinity could be predicted in coastal taxa. The steppe and mountainous areas of middle Eurasian biodiversity hotspots present a particular wealth of geophytes, (i) Mediterranean Basin; (ii) Caucasus, (iii) Irano-Anatolian, (iv) Mountains of Central Asia. Numerous species coming from those regions are cultivated as known ornamentals, however their tremendous potential could be widely used in changing climatic conditions. Simultaneously, their cultivation and dissemination may contribute to the protection of threatened taxa. The following may be noticed as particularly noteworthy, Allium sp., Asphodelus aestivus, Bellevalia forniculata, Colchicum sp., Corydalis caucasica, Crocus sp., Cyclamen sp., Drimia maritima, Eremurus sp., Erythronium caucasicum, E. dens-canis, Fritillaria sp., Iris sp., Hyacinthus litwinowii, Lilium ciliatum, Merendera sobolifera, Muscari sp., Narcissus sp., Nectaroscordium siculum, Pancratium maritimum, Romulea tempskyana, Scilla autumnalis, Sternbergia lutea, Tulipa sp., Ungernia sewerzowi.

Keywords: autumn flowering, bulb, corm, green areas, ornamentals, temperate climate, underground storage organ


The effect of treatment of ornamental bulb plants on the settlement of bulbs and the substrate by fungi during the period of rooting and on the growth and development of plants

Jacek Nowak1 (, Adam Wojdyła1, Leszek Orlikowski1, Jan Bocianowski2, Jacek Wiśniewski3, Emilia Waszkiewicz4

1The National Institute of Horticultural Research, Skierniewice, Poland 2Poznan University of Life Sciences, Poznan, Poland
3Gospodarstwo Ogrodnicze Jacek Wiśniewski Spółka Jawna, Rzeczycka, Poland 4Emi Agro Emilia Waszkiewicz, Otwock, Poland

The studies evaluated the effect of Bisteran (50% of silver-stabilized hydrogen peroxide) and the fungicides Biszop 80 WG (80% of captan), Signum 33 WG (67 g of piraclostrobin + 267 g of boscalid in 1 kg) and Yamato 303 SE (233 g of thiophanat methyl + 70 g of tetraconazole per l), used for dressing hyacinth and narcissus in the form of 30-minute soaking of bulbs to limit the development of fungi on bulbs and the substrate during the period of rooting in a cold store and their impact on plant growth and development. The research showed that silver-stabilized hydrogen peroxide (H2O2-Ag+) at a concentration of 2% to 10% and fungicides used to treat bulbs on limiting the development of fungi on bulbs and the substrate during the rooting period. W hen the hyacinth and narcissus were in full bloom, biometric measurements were made of the above-ground parts of the plants, showing the growth and quality of the plants, and the content of chlorophyll, flavonoids and the nitrogen balance index index (NBI index) were determined using the Dualex 4 meter. For most of the tested traits, it was found that silver-stabilized hydrogen peroxide (H2O2-Ag+) at a concentration of 2% to 10% and the tested fungicides significantly increased their parameters compared to control plants. However, depending on the tested plant species, the positive effect on the tested traits varied, therefore such studies must be carried out individually for a given plant species. It should be emphasized that none of the tested agents used to treat hyacinth and narcissus bulbs was phytotoxic. The obtained results may be useful for the practical application of hydrogen peroxide with silver as a completely safe agent for humans, animals and the environment in the form of dressing hyacinth and narcissus bulbs before rooting in a cold room.

The research was conducted as part of a research project co-financed by the European Union under the ‘Cooperation’ measure of the Rural Development Program 2014–2020 “Implementation of an improved product, innovative technology and production organization methods in the production of bulbous ornamental plants using high-pressure fogging of refrigerated rooms with silver-stabilized hydrogen peroxide”.

Keywords: bulb rooting, fungicides, fungi on bulb surface and substrate, hydrogen peroxide stabilized with silver, Hyacinthus, inhibition, Narcissus, plant growth and development


In vitro effect of some compounds on fungi developing on bulbs during their rooting

Jacek Nowak1 (, Adam Wojdyła1, Leszek Orlikowski1,
Jan Bocianowski2, Magdalena Ptaszek1, Anna Jarecka-Boncela1, Agnieszka Włodarek1, Anna Lisek1, Jacek Wiśniewski3, Emilia Waszkiewicz4

1The National Institute of Horticultural Research, Skierniewice, Poland 2Poznan University of Life Sciences, Poznan, Poland
3Gospodarstwo Ogrodnicze Jacek Wiśniewski Spółka Jawna, Rzeczycka, Poland 4Emi Agro Emilia Waszkiewicz, Otwock, Poland

The i n v itro e ffectiveness of Bi steran (5 0% of hy drogen pe roxide st abilized wi th si lver) an d the fungicides Biszop 80 WG (80% of captan), Signum 33 WG (67 g of piraclostrobin + 267 g of boscalid in 1 kg) and Yamato 303 SE (233 g of thiophanat methyl + 70 g of tetraconazole per l) added to potato–dextrose agar (PDA), on the in vitro growth of Neopestalotiopsis foedans, Penicillium olsonii, Rhizopus stolonifera and Trichoderma asperellum, isolated from peat and bulbs of hyacinthus, narcissus and tulip during their rooting was evaluated. The p roduct a pplied at concentrations ranging from 0.05% to 0.2%, inhibited the growth of N. foedans from 78.1% to 87%, and P. olsonii from 55.3% to 79% but did not influence t he c ulture d evelopment of R. stolonifera and T. asperellum or only slightly stimulated the growth. Bishop 80 WP at a concentration of 0.19% almost completely inhibited the growth of N. foedans, P. olsonii and R. stolonifera, while T. asperellum at 75%. Signum 33 WG at concentration of 0.15% almost completely inhibited the growth of N. foedans and P. olsonii, T. asperellum in 92%, while R. stolonifera in about 21%. Application of Yamato 303 at a concentration of 0.15% resulted in growth inhibition for the tested fungus N. foedans 93%, P. olsonii 44%, R. stolonifera 7% and T. asperellum 99%, respectively.

The research was conducted as part of a research project co-financed by the Eu ropean Union under the ‘Cooperation’ measure of the Rural Development Program 2014–2020 “Implementation of an improved product, innovative technology and production organization methods in the production of bulbous ornamental plants using high-pressure fogging of refrigerated rooms with silver-stabilized hydrogen peroxide”.

Keywords: fungi, fungicides, Hyacinthus, hydrogen peroxide stabilized with silver, Narcissus, tulip


Nutrient deficiencies affect growth and development of Curcuma ‘Golden Reign’

Soraya Ruamrungsri, Chaiartid Inkham, Kanokwan Panjama ( Chiang Mai University, Chiang Mai, Thailand

Curcuma ‘Golden Reign’ is a beautiful gigantic tropical flower. It can be utilized in various ways such as landscaping plants, potted plant and cut flower. However, there are limited data about nutrient deficiency symptoms in ornamental curcuma. Therefore, the purpose of this experiment was to study effect of nutrient deficiencies on growth and development of curcuma plant. The curcuma rhizomes were grown in a hydroponics system. The experimental design was completely randomized design (CRD) for 3 replications per treatment and, 2 plants per replication with 14 treatments, T1: plants were supplied with complete solution as control treatment (Hoagland’s solution), and T2-T14, plants were supplied with deficiency solutions of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), boron (B), manganese (Mn), zinc (Zn), copper (Cu), molybdenum (Mo) and deionized water, respectively. The results showed that at 18 weeks after planting, potassium deficiency treatment showed plant height lower than the control treatment. Moreover, the old leaves were burned, chlorophyll content in old leaves and young leaves were 26.50 and 31.20 SPAD unit, respectively. Magnesium deficiency treatment resulted in yellow color of old leaves and interveinal chlorosis. The shortest flower length was obtained from the boron deficiency treatment.

Keywords: fertilizer, flowering, ornamental curcuma, potted plant


Parks and gardens as a contributor to older people’s perceived well-being and health

Bożena Pawłowska (, Anna Herod, Bożena Szewczyk-Taranek University of Agriculture in Krakow, Krakow, Poland

Seniors are a group with specific requirements that also apply to the use of green spaces. The aim of the study was to analyse the relationship between the well-being and health of seniors and the perception and ways of using parks and gardens. Original non-standardised questionnaire was applied in the research, with: (1) self-developed questions regarding green areas, (2) questions about well-being, health and life satisfaction, and (3) the WHO-5 test. The survey was conducted in Poland, among people 61–98 years old. Analyses included descriptive statistics; frequency distributions; T-tests; ANOVA. Results indicated that, almost 90% of seniors declare that spending time outdoors is important or very important and those who describe their health as good or very good, 69% consider being outdoors as very important. In the group of respondents who describe their health as bad, only 50% recognise spending time outdoors as very important. People over eighty spend more than 7 hours a week in the garden, while younger seniors only from 1 to 3 hours a week. More than half of seniors (58%) prefer spending time in the garden, and only 22% favour the park. Seniors who feel very happy compared to seniors declaring non happy, often claim that a day spent in the garden contributes to a better quality of sleep and consider gardening as a form of physical activity. Unhappy seniors more likely declare that when they feel depressed, spending time in the garden lifts their spirits. Over 70% of seniors testify that pleasant memories are related to the garden from their childhood. The most remembered garden plants are: peonies (28% of respondents) and roses (26%), tomatoes (41%), and apples (38%). Research demonstrated that gardens and parks are an important contributor to older people’s health and well-being.

Keywords: elderly citizen, green care, nature experiences, quality of life


LED light affects the biochemical composition of Lilium candidum adventitious bulbs formed in vitro on a cytokinin medium

Bożena Pawłowska (, Piotr Pałka, Barbara Prokopiuk University of Agriculture in Krakow, Krakow, Poland

Lilium candidum (Madonna lily) is a bulbous geophyte that occurs naturally in the Mediterranean. It is characterized by early flowering in the season and pure white flowers with a strong pleasant fragrance. Bulb and flower extracts have been used in folk medicine, and scientific research has confirmed the presence of compounds with health-promoting properties. All this meant that the plants were obtained from natural sites and in some countries of origin the species is protected. We have evaluated biochemical composition of adventitious bulbs, contents of photosynthetic pigments (chlorophyll a + b and total carotenoids), soluble phenolics and soluble sugars in bulblets grown under different light conditions in vitro. Cultures were carried out under eight different LED lights, with fluorescent lamp and darkness used as a control. Murashige and Skoog medium has been enriched with 5 μM 6-benzylaminopurine (BA) and 0.5 μM 1-naphthaleneacetic acid (NAA). Bulbs formed under the mixture (7:3) of red and blue LED light (RB) were characterized by the highest content of all tested pigments. Lower but still high values were characteristic of bulblets from the white LED light (WLED) and RB light enriched with a UV diode (RBUV). This relationship was especially visible for chlorophyll a and b. WLED and RBUV, however, inhibited the synthesis of soluble phenolics, which was stimulated by blue LED light (B). In the case of soluble sugars, the light of the fluorescent lamp (FL) and WLED gave similar high values. Intermediate values were obtained under blue LED light. LED light can therefore be used to modify the biochemical composition of L. candidum bulblets in in vitro cultures. Blue or white LED light seem particularly valuable for this purpose.

Keywords: photosynthetic pigments, soluble phenolics, soluble sugars


Single-node cuttings constitute a highly efficient Pennisetum ‘Vertigo®’ propagation material

Bożena Pawłowska (, Barbara Prokopiuk, Anna Kapczyńska University of Agriculture in Krakow, Krakow, Poland

Pennisetum ‘Vertigo®’ (Poaceae) is a newly released tender perennial hybrid most often recomended for container display. Because of pollen-and seed-sterility it is a vegetatively propagated ornamental grass with unique characteristics (burgundy-leaved, to 1.5 m tall). In present study the effect of four types of shoot single-node cuttings (with 1st, 2nd, 3rd, and 4th node, respectively, counting from the base of the grass crown) and two rooting media (peat and perlite) on the rooting proces were assessed. After a month it was found that, depending on the combination, the cuttings were 48–98% rooted, producing 1.4–2.6 roots per cutting, each 7.3–11.6 cm long. One shoot was formed on the rooted cutting, with 3.1–4.4 leaves on it, and the entire above-ground part of the rooted plant was 10.5–32.8 cm, depending on the combination. Results showed that, sterilePennisetum ‘Vertigo®’ can be successfully propagated from shoot cuttings, but the rooting process depended on the type of cutting, with the benefit of those made from the nodes proximal to the grass crown.

Keywords: grass nodes, ornamentals, Poaceae, rooting media, vegetative propagation


The senescence of perianth and corona in cut daffodil ‘Dutch Master’ flowers

Julita Rabiza-Świder (, Ewa Skutnik, Kamil Lutostański Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland

Daffodils are one of the most known bulbous plants, most popularly chosen just after tulips and lilies. The most common, and also the most popular for cut flowers, are the Trumpet daffodil cultivars. The aim of the study was to evaluate the changes in cut daffodil ‘Dutch Master’ flowers and to find the response that the perianth senescence different way than corona in cut daffodil flowers and if the senescence of daffodil cut flowers is correlated with programmed cell death symptoms. Flower senescence is a highly organized process comprising structural, biochemical and molecular changes, which is the last stage of flower development, finally leading to death of an organ or organism. In order to evaluate the changes occurring during the senescence of daffodil ‘Dutch Master’ cut flowers, the content of total and reducing sugars, free proline, malondialdehyde, hydrogen peroxide, catalase activity and the degree of degradation of cell nuclei were determined. The effect of a preservatives based on nanosilver (0.1 or 1.0 mg·dm−3) and 10% sucrose on postharvest flower quality and the value of selected senescence parameters was also investigated. It was shown that during the senescence of cut daffodil flowers there is a decrease in the content of total and reducing sugars, a decrease in malondialdehyde content, an increase in free proline, hydrogen peroxide and an increase in catalase activity. One of the symptoms of flower senescence was the degradation of cell nuclei. Typical senescence processes occurred faster in the perianth than in the corona. The use of a preservative containing nanosilver with 10% sucrose does not affect the rate of flower bud opening, but extends the vase life of daffodil flowers by 2–4 days. This preservative also increases the reducing sugars content, decreases the free proline and hydrogen peroxide content and affects the decrease of the catalase activity.

Keywords: free proline, malondialdehyde, nanosilver, oxidative stress, postharvest life, preservatives, total and reducing sugars


Organic and conventional agriculture in tulip flower greenhouse production

María de los Ángeles Rodríguez Elizalde (, José Alberto Ortiz Texón, Mateo Vargas Hernández, Amando Espinosa-Flores, Claudio Arturo Pérez Mercado

Universidad Autónoma Chapingo, Texcoco, México

This study evaluated the development of tulip flowers in pots using different substrates in two production systems: organic and conventional under greenhouse conditions. The organic production system consisted of inoculating beneficial microorganisms (arbuscular mycorrhizal fungi, Trichoderma spp., and Azotobacter spp.) and using organic fertilization. The conventional system used commercial fertilizers and agrochemicals. The experimental design was completely randomized, with ten treatments and five replications, considering each pot as an experimental unit. The substrates included mixtures of tezontle (TZ), leaf mold (LM), peat moss (PM), and vermicompost (VC). All substrates included 20% TZ, and either LM and PM alone (80%) or a combination of two substrates (40% LM and 40% PM, 40% LM and 40% VC, or 40% PM and 40% VC). The tulip flowers were grown in the five substrate combinations using either organic or conventional (chemical) fertilization. Yield and plant quality (plant height, stem diameter, bud diameter, and open corolla diameter) were evaluated. The results of the contrast analysis showed that the organic agriculture system was superior to the conventional system since the tulips showed significantly larger stem and flower diameters. The best substrate for producing this species was the mixture of 80% LM + 20% TZ. Our study shows that tulip flower production in greenhouse conditions is feasible under the organic agriculture model.

Keywords: arbuscular mycorrhizal fungi, Azotobacter, Trichoderma, Tulipa spp.


Light emitting diode for off-season flowering of Curcuma alismatifolia Gagnep

Soraya Ruamrungsri (, Chiartid Inkham, Kanokwan Panjama Chiang Mai University, Chiang Mai, Thailand

Curcuma alismatifolia Gagnep is one of the popular tropical flowers in the world market. Seasonal flowering in Thailand is in rainy season during July-August and plant goes to dormancy during December to February then start to sprout again in May. Off-season flower forcing could be done to serve market demand for all year round. Since Curcuma alismatifolia is facultative long day plant therefore this research was aimed to use different type of artificial light supplement for flower quality improvement. Rhizomes were stored in 15°C cold room for 6 months then they were grown in plastic bags using soil, rice husk charcoal, sand, rice hull and coconut dust with the ratio of 1:1:1:1:1 as growing media under plastic greenhouse (24°C, 65% RH and 1,000 μmol m−2 s−1). The experimental design was completely randomized design with 6 treatments i.e. treatment 1) no supplement lighting, treatments 2–3) plants were supplied with different artificial lighting using 13 and 18 W of light emitting diode (LED), treatment 4–5 using 15, 24 W of compact fluorescent lamps (CFL) and treatment 6) using 400 W of high pressure sodium (HPS) lamp. Supplement lighting was applied at 20.00–22.00 o’clock every day until plant dormancy. Irrigation was done every day and 15 N-15 P2O5-15 K2O fertilizer with 2 g/pot was supplied every 2 weeks. The results showed using LED lighting could promote the flower quality in term of flower stalk length and inflorescence height than control treatment. However, plants supplied with 400 W HPS gave the highest of plant height, flower stalk length, inflorescence height than the other artificial light sources and control treatment. Rhizome quality also was promoted by using artificial lighting supplement compared to control treatment.

Keywords: energy saving, flower quality, forcing, LED, supplement lighting


The effect of postharvest treatments with commercial preservatives on keeping qualities of cut peony flowers

Ewa Skutnik (, Julita Rabiza-Świder, Sutrisno
Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland

Special treatments and various preparations are used during all phases of the market chain to sustain life of cut flowers and to maintain their good quality. Recently, cut peonies have gained worldwide popularity so the development of appropriate postharvest treatments is in order. In this experiment two types of flower preservatives produced by Chrysal International and Floralife were tested on several peony cultivars: the so called „trade” preparations used to sustain flower life during the turnover (Chrysal Professional 2, Floralife 200) and the so called „flower food” preparations used to prolong the flower vase life (Chrysal Clear, Floralife 300). The first were applied for 72 hours after harvest, i.e. the period simulating the turnover phase; after that flower food preparations were used. The treatment effects were compared with those of the standard preservative composed of 2% sucrose plus 200 mg L1 8-hydroxyquinoline (8-HQC), and distilled water was used as the control. The cultivars tested were: ‘Charles Binder’, ‘Gayborder June’, ‘Jamachina’, ‘Laura Dessert’, ‘Marguerite Gaudichau’, ‘Othello’ and ‘Vogue’, all of which responded poorly to the treatments and in all cases responses were cultivar-specific. The vase life was prolonged in only 9 out of 49 treatments, with ‘Charles Binder’ and ‘Jamachina’ showing no positive reaction to any of the holding solutions while 4 out of 7 treatments increased the vase life of ‘Gayborder June’. The rate of bud opening was different among cultivars and flower diameters increased in ca 50% of cases – in 24 out of 49 treatments. As the responses to treatments were so cultivar-specific, any recommendations for specific preparations must be preceded by tests with individual cultivars.

Keywords: flower diameter, flower food, re-hydrating, vase life


The possibility of using new plant growth regulators in micropropagation of Polish tulip (Tulipa L.) cultivar ‘Heart of Warsaw’

Dariusz Sochacki1 (, Przemysław Marciniak1, Aleksandra Goszcz1, Maria Ciesielska1, Janina Zaród1, Sutrisno1, Monika Drąg2, Agnieszka Żukowska2

1Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland 2The Royal Castle in Warsaw – Museum, Warsaw, Poland

High demand for tulip bulbs and accelerated introduction of new cultivars to the market prompt further work on improving the method of in vitro propagation of this genus. The object of the research was the new Polish cultivar ‘Heart of Warsaw’ (= ‘Serce Warszawy’, in Polish), baptized at the Royal Castle in Warsaw in 2019 at the opening of the Lower Gardens, the reconstruction of which was the culmination of the post-war rebuilding of the Castle. Meta-topolin(mT) – new aromatic cytokinin in micro-propagation of tulip and karrikin (KAR1) – completely new plant growth regulator (PGR) – were checked and compared with other PGRs at different stages of in vitro propagation on Murashige and Skoog (MS) medium using procedure of cyclic shoot multiplication. The results obtained from the regeneration and multiplication of the ‘Heart of Warsaw’ tulip show that it has been possible to replace so far used thidiazuron (TDZ) and 2-isopentyladenine (2iP) by mT at concentration of 5 mg L−1. However, the results with supplementation of the MS medium with mT were mostly not better, but also not different from those obtained on media with TDZ and 2iP. The expected positive effect of KAR1 on the shoot proliferation of the ‘Heart of Warsaw’ tulip has not confirmed so far, indicating the need for further research. In conclusion, the method of cyclic tulip shoot multiplication using mT can be used to accelerate the propagation of the new tulip cultivar under study.

Keywords: in vitro, karrikin, KAR1, meta-Topolin, mT, PGRs, Royal Castle in Warsaw


Evaluation of ploidy level and genome size of Hippeastrum

Dariusz Sochacki1 (, Przemysław Marciniak1, Agnieszka

Marasek-Ciołakowska2, Małgorzata Podwyszyńska2, Monika Marat2, Małgorzata Zajączkowska1

1Warsaw University of Life Sciences, Section of Ornamental Plants, Warsaw, Poland 2The National Institute of Horticultural Research, Skierniewice, Poland

Hippeastrum Herb. belongs to the family Amaryllidaceae. The genus includes about 80 taxa found in South American countries. In commercial cultivation, the most frequently cultivated varieties are those belonging to H. hybridum, which have been obtained by crossing several wild species (H. vitatum, H. leopoldii, H. reginae, H. aulicum, H. pardinum). The goal of most breeding programs in the world is to improve flower attractiveness and plant resistance to Phoma narcissi. Information on the registration of new cultivars in 2018–2022, published by the Dutch Royal General Bulb Growers’ Association (KAVB), shows that as many as 158 new cultivars have been registered. The largest number of registered cultivars belongs to the Galaxy group (65 cultivars). In 1993, Hippeastrum ×chmielii, a hybrid characterised by strong growth, a high vegetative reproduction rate and no apparent dormancy period, was bred at the Warsaw University of Life Sciences – SGGW, Poland. However, the flowers of this hybrid are relatively small and there islittle variation in colour, oscillating between red and orange. Therefore, twoofitsbreedingclones(Nos.6and18)wereusedforfurthercreative breeding. The aim of the present study was to evaluate the ploidy level and genome size of selected individuals derived from crosses between H. ×chmielii (clones 6 and 18) and selected cultivars of H. hybridum (‘Gervase’, ‘Rio Negro’ and ‘Royal Velvet’). The ploidy levels and genome size of the parental forms and 15 selected breeding clones derived from the crossings were evaluated by flow cytometry and based on chromosome number using Feulgen and DAPI staining methods. The results obtained indicate that a large part of the population studied (14 genotypes) are tetraploid forms (2n = 4x = 44), and the size of their genomes ranges from 57.44 to 61.61 pg of 2C DNA. Four triploid genotypes (2n = 3x=33) were also detected in the population, whose 2C DNA content was 43.68–47.08 pg. The cultivar ‘Rio Negro’ has a diploid somatic chromosome number of 2n = 2x = 22 andgenome size of 32.63 pg 2C DNA. The cultivar ‘Gervase’ proved to be a mixoploid with tetraploid (60.29 pg) and aneuploid (47.94 pg) genomes based on flow cytometry analysis.

Keywords: breeding clones, DAPI, Feulgen, flow cytometry, Hippeastrum ×chmielii


Ecological aspects of Tulip virus X in the Netherlands

Ineke Stijger1 (, Martin Verbeek1, Iris Stulemeijer2, Frank Kreuk3

1Wageningen University and Research, Wageningen, Netherlands 2BKD, Lisse, Netherlands
3Vertify, Zwaagdijk, Netherlands

Tulip virus X (TVX) is a member of the genus Potexvirus and can cause symptoms in tulips consisting of fine streaks on leaves and fl ow ers. Being apo te xvirus, TV X sp reads through contact between plants and the usage of tools. Also, transmission by several mite species during storage of the bulbs is common. However, there have been reports of a soil-related transmission, but there was no evidence of any vector involved in such transmission. In relation to the growing fields, it is remarkable that TVX has a broad host range and can be found in various weeds. Recent studies revealed the presence of TVX in tulips, weeds, soil and in water of ditches around the tulip fields. T VX i n s oil w as i nfectious o n i ndicator p lants for months after inoculation of the soil. Currently, the biological significance of TVX in weeds and the detection of the virus in water is under investigation.

Keywords: Potexvirus, soil, tulips, TVX, weeds


Conservation of plant genetic resources in Lithuania

Gitana Stukeniene (, Audrius Skridaila Vilnius University Botanical Garden, Vilnius, Lithuania

The study and conservation of plant genetic resources (PGRs) in Lithuania has a long tradition. Since 1994, efforts on PGRs have been concentrated within the National Programme on Plant Genetic Resources. This Programme encompasses the conservation and research of the genetic resources of agricultural and horticultural crops, medicinal and ornamental plants, and forest trees. For the implementation of this Programme, the collaboration of eight scientific institutions started, including Vilnius University Botanical Garden and Vytautas Magnus University Kaunas Botanical Garden. In 2001, the Seimas (Parliament) of the Republic of Lithuania adopted the Law on National Genetic Resources of Plants, which regulates the accumulation, preservation, and use of National PGR and stipulates how to provide for the sustainable use of these resources, protect them from devastation, extinction and compete with destruction as well as to save the biological diversity. According to the provisions of this law, PGR, which have ecological, selective, and economic value for the Republic of Lithuania, are selected and included in the central database of the National PGRs. It might be plant cultivars, plant populations or their parts, single plants or their groups, or re-productional parts of plants (seeds, pollen, embryos, meristematic tissues, buds, sprouts, etc.). The Plant Gene Bank (currently – State Forest Service) with coordination centers of different plant groups (agricultural plants, forest trees, fruits and vegetables, ornamental plants, and medicinal plants) has been established. At the end of 2022, there were 5914 accessions on the National List of PGR in Lithuania. In 2022, the State Forest Service signed an agreement with the Nordic Center for Genetic Resources NordGen. According to this agreement, NordGen will store the seeds of 123 accessions of Lithuanian PGR in the Svalbard Global Seed Vault.

Keywords: biological diversity, database, ornamental crops, PGRs, preservation


Interspecific hybridization between Cyclamen hederifolium Aiton and C. purpurascens

Takejiro Takamura (, Shin Mukai, Masaki Kubota, Takako Narumi-Kawasaki

Kagawa University, Kagawa, Japan

In recent years, horticultural cyclamen (Cyclamen persicum) cultivars have been used as garden plants as well as indoor potted plants in Japan. There are, however, few suitable cyclamen cultivars for growing in a garden in Japan, yet almost all cyclamen cultivars have been bred as indoor potted flowers. Nearly all the horticultural cyclamen cultivars have been bred through intraspecific cross-breeding in C. persicum, whereas some wild species in the genus Cyclamen have useful characteristics. C. hederifolium is one of the most vigorous and hardy species in the genus Cyclamen. Although almost all Cyclamen species, including C. hederifolium, have a dormant period in their life cycle in Japan, C. purpurascens doesn’t have this trait. Therefore, interspecific crosses between C. hederifolium and C. purpurascens were performed. After the interspecific crosses, ovule cultures with and without chromosome doubling were also examined. The interspecific hybrids were obtained by the ovule culture, and some plantlets were expected to be amphidiploids. There was, however, no amphidiploid among the flowering hybrids. The hybrids were sterile, and showed an intermediate life cycle between those of C. hederifolium and C. purpurascens.

Keywords: hybrid, interspecific crosses, ovule culture


Effect of foliar fertilization on bulblet formation from leaf cuttings of Lachenalia

Jadwiga Treder1 (, Patrycja Kowalicka1, Anna Jakubczyk1, Anna Kapczyńska2

1The National Institute of Horticultural Research, Skierniewice, Poland 2University of Agriculture in Krakow, Krakow, Poland

Lachenalia species come from South Africa and have recently become more and more popular as attractive pot plants. Vegetative propagation methods of Lachenalia mostly include: seeds, side bulbs formed out of a mother bulb, bulbils (aerial bulblets) and bulblets production on leaf cuttings. In commercial reproduction, the method of leaf cuttings is more often used than in-vitro propagation. The aim of the study was to determine the effect of additional foliar fertilization using Agroleaf P fertilizer (12:52:5 +TE) during mother plants cultivation of two Lachenalia cultivars: ‘Ronina’ and ‘Rupert’. It is assumed that increased P levels stimulate rooting in many species. Bulbs were planted in autumn into peat substrate and cultivated in pots at controlled climate chambers. Two months after planting the bulbs, when leaves reached 15–20 cm in length and 2.0–3.5 cm in width, the plants were sprayed three times at weekly intervals with 0.2% Agroleaf P. Control plants were sprayed with water. Just before flowering (mid of December) randomly selected leaves reached 20 cm in length and 2.03 cm in width from both treatments were cut off at the plant base plants. Leaves cuttings were rooted in plastic boxes using and mixture of vermiculite and sand (10:1 v:v). Bulbils production on each cutting were evaluated five months after planting. Application of P foliar fertilizer during mother plant cultivation stimulated the number of bulbils formation in both cultivars. However, the bulbils fresh mass was not influenced by leaf spraying.

Keywords: Cape hyacinth, geophyte, ‘Ronina’, ‘Rupert’


Effect of elicitors on Fusarium development in tulip bulbs

Sjoerd van Vilsteren (, Kirsten Leiss, Johanna Bac-Molenaar

Wageningen University and Research, Bleiswijk, Netherlands

Tulip growers are affected by the fungus Fusarium oxysporum f. sp. tulipae (FOT), which can cause rot and significantly reduce yields. FOT could develop thereby causing yield loss in open field conditions with a soil temperature above 12°C, but also during the storage after harvest. Currently there is little experience with the use of elicitors in postharvest conditions. This study tested the effect of elicitors on FOT development in tulip bulbs, cultivars ‘Leen van de Mark’ and ‘Miranda’ in two subsequent years 2022 and 2023. In 2022, we tested several doses of the plant hormones, jasmonic acid and salicylic acid. In 2023, we tested the plant hormones and in addition acibenzolar-S-methyl, and Bacillus amyloliquefaciens. Within a week after harvest, tulip bulbs were dipped in elicitor/bacterium solutions, and dipping in water was used as control. One week after treatment, the bulbs were damaged to increase the chance of infection with FOT. Two types of damage treatment were applied: by either scratching with a knife or rubbing on a stone. Immediately after damaging, the bulbs were exposed to FOT by dipping in a solution with FOT spores (mixture of different strains) and disease symptoms were assessed in the following months on a two-weekly basis. In both years, salicylic acid treatment led to a decrease in the number of infected bulbs resulting in almost half of the infection rate compared to control with water. In 2023, acibenzolar-S-methyl and Bacillus amyloliquefaciens showed the same trend, lower bulb infection rate after application. In 2023, bulbs treated with jasmonic acid showed higher infection rate than water control, suggesting antagonistic roles of the two plant hormones jasmonic acid and salicylic acid. These findings will help to come to a tulip cultivation and storage system that is future-proof, meaning not dependent on high-risk pesticides and with low emissions to the environment.

Keywords: bulbs, elicitors, fungi, Fusarium oxysporum f. sp. tulipae, storage, Tulipa


Wood fibre as a component of sustainable substrates for pot plant production of Helenium hybridum

Agnieszka Zawadzińska1 (, Piotr Salachna1, Rafał Piechocki1, Jacek Nowak2, Anna Pietrak1

1West Pomeranian University of Technology, Szczecin, Poland
2The National Institute of Horticultural Research, Skierniewice, Poland

For perennial container growers a major challenge in the next few years will be the necessity to use sustainable substrates with limited peat content and, in the future peat-free substrates. In this context, substrate producers have recently turned their attention to wood fibre (WF) as a renewable organic material that can partly replace high peat (SP). In this experiment, four substrate mixtures containing in different proportions wood fibre, high peat, and local raw materials: green compost (GC), fen peat (FP) and brown coal (BC) were tested. For trial, young plants of Helenium hybridum ‘Fuego’ were potted in the following mixtures: (T1) SP 100% used as control; (T2) WF 20%, SP 30%, GC 20%, FP 20%, BC 10%; (T3) WF 30%, SP 20%, GC 20%, FP 20%, BC 10%; (T4) WF 40%, SP 20%, GC 20%, FP 10%, BC 10%. The height and width of plants grown in mixtures containing 20–40% of wood fibre (T2, T3 and T4) and the diameter of their flower heads did not differ strongly from plants grown in peat control (T1). The highest fresh and dry plant biomass, leaf greening index and number of flower heads had the plants grown in a mixture with 20% of wood fibre (T2). There was significant reduction in the fresh and dry weight plant biomass in the medium containing 40% of wood fibre (T4) versus those grown in peat. Generally, Helenium plants can be grown in a substrate containing up to 30% of wood fibre mixture without loss of biomass and plant quality.

Keywords: growing media, perennials, sneezeweed, SPAD


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