Search Results (55)

Rosa hybrida is a globally important ornamental species, but its economic and aesthetic value is often compromised by rose black spot disease (Diplocarpon rosae). Effective monitoring and early detection are essential for disease management. This study investigated physiological and biophysical responses to infection in a resistant cultivar (‘Carefree Wonder’) and a susceptible cultivar (‘Red Cap’) using electrical impedance spectroscopy (EIS), biochemical assays, and ultrastructural analysis. Key EIS parameters (r_i, r_e, τ), reducing sugar and free proline content, chitinase and β-1,3-glucanase activities, and chloroplast ultrastructure were monitored. The results showed that ‘Carefree Wonder’ had a higher initial EIS arc magnitude and osmolyte levels than ‘Red Cap’. Following infection, ‘Red Cap’ displayed earlier and more pronounced increases in EIS arc magnitude, while ‘Carefree Wonder’ responded more gradually. Reducing sugar and proline levels increased in both cultivars, with earlier accumulation in the resistant cultivar. Notably, extracellular resistivity (r_e) exhibited strong positive correlations with reducing sugar (R² = 0.479), free proline (R² = 0.399), chitinase (R² = 0.399), and β-1,3-glucanase activities (R² = 0.401). These findings highlight r_e as the most reliable EIS-derived indicator for early, non-destructive detection of rose black spot resistance. This study supports the potential of EIS for rapid disease diagnostics in rose breeding and cultivation. Full article

Hybrid tea roses (Rosa hybrida) are economically important horticultural crops and highly susceptible to heat stress, which significantly impacts flower quality and yield. As a key member of the heat shock protein (HSP) family, HSP70 protein acts as a molecular chaperone and exhibits diverse abiotic stress response functions in plants. A total of 113 HSP70 transcription factors (TFs) with varying physical and chemical properties were identified in the genome of hybrid tea rose. Phylogenetic analysis showed that the identified TFs could classify into three (I, II, and III) subfamilies, with most members (51 TFs) falling in subfamily II. Wide gene structural variations were observed among the three subfamilies, with group I and II members lacking introns, while group III members only harbored 1~4 exons and introns. Numerous cis-acting elements associated with abiotic stress, hormone response, growth and development responses, as well as light response were detected in the HSP70 gene promoters. In addition, protein interaction networks predicted a wide range of interactions between different hybrid tea rose HSP70 subfamilies. Gene expression analysis revealed that 57 HSP70 genes had strong organ specificity and response to heat stress in the hybrid tea rose plants. Notably, the expression levels of two RhHSP70 genes, RhHSP70-69 and RhHSP70-88, were significantly increased after heat stress, indicating that these two genes might be crucial for plant heat stress response. Subcellular localization of RhHSP70-69 and RhHSP70-88 revealed that their proteins were located in the nucleus. Our results are not only useful for future evaluation of the regulatory roles of RhHSP70 genes in the hybrid tea rose growth and development, but also provides key genes for future molecular breeding of heat tolerant plants. Full article

Objective: This study aimed to elucidate the regulatory mechanism of an auxin amide hydrolase gene (IAA-Leucine Resistant1-like Hydrolase, RhILL1) in the petal pigmentation of rose (Rosa hybrida), providing theoretical insight into the hormonal regulation of flower coloration at the molecular level. Methods: Using petals at Stage 3 (S3) of the cut rose cultivar ‘Pink Floyd’ as experimental material, we cloned the rose auxin amide hydrolase gene RhILL1 and validated its function via virus-induced gene silencing (VIGS). The expression levels of anthocyanin biosynthetic genes, anthocyanin content, and auxin (IAA) levels were analyzed to assess the role of RhILL1 in petal pigmentation. Results: The full-length open reading frame (ORF) of RhILL1 was cloned, spanning 1326 bp and encoding a 441-amino-acid protein harboring two conserved domains, Peptidase_M20 and M20_dimer, characteristic of the ILL1 protein family. Functional characterization was performed using VIGS. Quantitative real-time PCR (qRT-PCR) revealed that RhILL1 expression progressively increased from the Green (G) stage to S3, correlating with intensified petal coloration. Silencing RhILL1 resulted in visibly lighter petals, the reduced expression of anthocyanin biosynthetic genes, and a significant decrease in endogenous indole-3-acetic acid (IAA) levels compared with controls. Moreover, exogenous application of 10 μM naphthaleneacetic acid (NAA) to petals significantly preserved petal pigmentation. Conclusion: These findings suggest that RhILL1 contributes to the development and maintenance of petal coloration in rose, likely by modulating IAA levels, thereby influencing the expression of anthocyanin biosynthesis-related genes. Full article

Soybean is an important economic oilseed crop, being rich in protein and plant oil, it is widely cultivated around the world. Soybeans have been shown to establish a symbiotic nitrogen fixation (SNF) with their compatible rhizobia, resulting in the formation of nodules. Previous studies have demonstrated the critical roles of phytohormones, such as abscisic acid and cytokinin, in the process of legume nodulation. The present study investigated the role of GmWRKY17, a homolog of Rosa hybrida (Rh)WRKY13 in regulating plant immunity through cytokinin content and abscisic acid signaling in soybean nodulation. Utilizing real-time PCR and histochemical staining, we demonstrated that GmWRKY17 is predominantly expressed in soybean root nodules. Subsequently, we analyzed the function of GmWRKY17-overexpression, RNA interference (RNAi), and the CRISPR/Cas9 system. Overexpression of GmWRKY17 significantly increases soybean nodule number, while RNAi or CRISPR/Cas9-mediated knockout of GmWRKY17 resulted in a dramatic repression of nodule formation in soybeans. These results highlight that GmWRKY17 functions as a positive regulator involved in soybean nodulation. Furthermore, manipulation of GmWRKY17 expression impacts the expression of genes associated with the nod factor (NF) signaling pathway, thereby influencing soybean nodulation. This study demonstrated that WRKY-type transcription factors are involved in the regulation of legume nodulation, offering new light on the molecular basis of the symbiotic interaction between legumes and rhizobia. Full article

Rose is one of the most popular ornamental plants worldwide. The double-flower trait, referring to flowers with extra petals, has been a key focus in rose breeding history. However, the genetic mechanisms regulating petal number in roses are still not fully understood. Here, we identified the CUP-SHAPED COTYLEDON 3 (RhCUC3) gene in the miniature rose (Rosa hybrida ‘Eclair’). The expression of RhCUC3 was high during the petal and stamen primordium differentiation stages but declined sharply during pistil primordium development. RhCUC3 belongs to the NAM/CUC3 subgroup of NAC transcription factors and is localized in the nucleus. The transcript level of RhCUC3 increased significantly with ABA and GA treatments and was inversely down-regulated with MeJA and 6-BA treatments. Silencing RhCUC3 using virus-induced gene silencing (VIGS) in rose ‘Eclair’ significantly decreased the number of petaloid stamens and normal petals while slightly increasing the number of stamens. Additionally, the expression of RhAG and RhAGL, two MADS-box genes associated with floral organ identity, was significantly higher in TRV-RhCUC3 compared to the TRV control. These findings suggest that RhCUC3 enhances stamen petaloidy and petal number, potentially by modulating the expression of RhAG and RhAGL, providing new insights into the function of NAC transcription factors in plants. Full article

The presence of bioactive compounds in plants with red flowers constitutes a valuable natural resource for the food, pharmaceutical, and medical industries. This paper aims to highlight these characteristics to facilitate the selection of extracts according to market needs. The analyzed parameters can provide valuable insights into the compositional variability of the five red flower plants, as new sources of bioactive compounds and natural antioxidants of plant origin. Five plants with red flowers (Magnolia liliiflora, Chrysanthemum morifolium, Hibiscus sabdariffa, Petunia grandiflora, Rosa hybrida L.) were selected and investigated regarding their polyphenol concentration, total anthocyanins, antioxidant activity, phenolic compounds, and antimicrobial activity. Total polyphenols were found in concentrations ranging from 75.17 ± 0.16 mgGAE/g (C. morifolium) to 107.49 ± 0.19 mgGAE/g (R. hybrida L.), and total anthocyanins between 14.99 ± 0.13 mg Cy-3-Glu/g and 21.66 ± 0.18 mg Cy-3-Glu/g. The antioxidant activity DPPH/IC50 mg/mL for the extract from R. hybrida L. flowers reached a value of 29.35 ± 0.17 mg/g, with ABTS and FRAP achieving maximum values of 49.89 ± 0.24 mmol TE/g and 48.68 ± 0.23 mmol TE/g, respectively. The antibacterial activity was particularly evident against strains commonly encountered in human pathology, Escherichia coli and Staphylococcus aureus, with reduced or no impact on strains of Pseudomonas fluorescens and Proteus mirabilis. The results demonstrated that the extracts from the selected, red-flowered plants contain valuable biologically active compounds in generous quantities, thus recommending their use in the food, pharmaceutical, and medical sectors. Full article

Rosa hybrida is one the most commonly cultivated ornamental plant of economic importance and faces major challenges under heat stress. Melatonin has been widely shown to regulate plant stress response; however, the exact mechanism involved in heat stress in R. hybrida has yet to be determined. Here, we observed that R. hybrida in vitro plantlets supplemented with melatonin in the culture medium exhibited higher chlorophyll content, relative ion leakage, and fresh weight after 12 d of high-temperature treatment; the optimal concentration was established at 5 mg/L. Using molecular and biochemical techniques, we explored the roles of a melatonin synthase gene RhCOMT1, which expression was influenced by heat stress and melatonin. RhCOMT1 was located in the nuclear-cytoplasmic under ambient conditions, while heat stress translocated the distribution of RhCOMT1 to chloroplasts. Overexpression of RhCOMT1 in rose petal enhanced thermotolerance, and silencing of RhCOMT1 reduced thermotolerance via affect H₂O₂ content and relative ion leakage. These findings collectively emphasize the pivotal role of melatonin in enhancing thermotolerance to R. hybrida by alleviation of oxidative stress, through modulation of RhCOMT1 expression and location. Full article

Roses are one of the most important flowers applied to landscape, cut flowers, fragrance and food industries widely. As an effective method for plant reproduction, the regeneration via somatic embryos is the most promising method for breed improvement and genetic transformation of woody plants. However, lower somatic embryogenesis (SE) induction rates and genotypic constraints impede progress in genetic transformation in rose. This study describes a plant regeneration system for the famous red cut flower cultivar Rosa hybrida ‘Carola’. The stems without petioles cultured on Murashige and Skoog (MS) medium supplemented with 1.0 mg·L⁻¹ 6-benzylaminopurine (6-BA), 0.05 mg·L⁻¹ a-naphthalene acetic acid (NAA) and 30 g·L⁻¹ sucrose showed the maximum proliferation coefficient of shoots with 3.41 for the micropropagation system. We evaluated the effects of different plant growth regulators (PGRs) on the induction, proliferation and conversion of somatic embryos. The induction rate of calli reached 100% on MS medium supplemented with 2.0 g·L⁻¹ NAA and 30 g·L⁻¹ glucose. The highest induction rate of somatic embryos achieved a frequency of 13.33% on MS medium supplemented with 2.0 mg·L⁻¹ zeatin (ZT), 0.1 mg·L⁻¹ NAA and 30 g·L⁻¹ glucose. The most suitable carbohydrate with 60 g·L⁻¹ glucose resulted in a proliferation rate of somatic embryos (4.02) on MS medium containing 1.5 mg·L⁻¹ ZT, 0.2 mg·L⁻¹ NAA and 0.1 mg·L⁻¹ gibberellic acid (GA₃). The highest somatic embryos germination rate (43.33%) was obtained from the MS medium supplemented with 1.0 mg·L⁻¹ 6-BA, 0.01 mg·L⁻¹ IBA and 30 g·L⁻¹ glucose. Finally, the germinated somatic embryos successfully rooted on 1/2 MS medium containing 1.0 mg·L⁻¹ NAA, 30 g·L⁻¹ sucrose, and the vigorous plantlets were obtained after hardening-off culture. This study provided a stable and efficient protocol for plant regeneration via somatic embryos in R. hybrida ‘Carola’, which will be beneficial to the further theoretical study and genetic improvement in roses. Full article

Drought stress is an important factor that reduces plant biomass production and quality. The APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) gene family is widely involved in biological processes such as plant growth, development, and stress response. However, the characteristics of the AP2/ERF gene family in hybrid tea rose (Rosa × hybrida) and their potential functions in responding to drought stress are still unclear. In the current study, 127 AP2/ERF genes were identified in hybrid tea rose. Phylogenetic analysis showed that the corresponding 127 AP2/ERF transcription factors belonged to five subfamilies. There was a large number of cis-acting elements in the AP2/ERF gene promoters related to regulation of stress response, growth and development. By examining the RNA sequencing data in the PlantExp database, the RhAP2/ERF genes exhibiting tissue-specific and stress-responsive expression in rose were identified. Furthermore, three candidate RhAP2/ERF genes (RhDREB36, RhERF59, and RhDREB44) that might participate in drought response were determined via qRT-PCR analysis in rose cultivars under drought treatment. Subcellular localization analysis revealed that RhDREB44 was located in the nucleus. These results provide a foundation for exploring the regulatory functions of RhAP2/ERF genes in the growth and development of roses, as well as for selecting key genes for future molecular breeding. Full article

Although they have been extensively studied in many species of the genus Rosa L., garden roses’ hips have largely been overlooked. To investigate their potential use in the food industry, this study evaluated five cultivars from ‘Aurora’ collection: ‘Purple Aurora’, ‘Berry Bush Aurora’, ‘Aromatic Aurora’, ‘Butterfly Aurora’, and ‘Rugose White Aurora’. Morphological characterization, along with the assessment of the phenolic profile, vitamin C levels, and biological activities—including antioxidant and neuroprotective effects—was conducted. The fruit mass reached 5.15 g, while the mesocarp mass ranged from 3 to 4 g, resulting in a mesocarp-to-fruit ratio of over 75%. The total phenolic content ranged from 37.1 to 63.9 mg GAE/g de, while total flavonoids were present in amounts from 0.85 to 2.14 mg QE/g de. Rosehip extracts from four out of five cultivars exhibited a very high vitamin C content, reaching 2384 µg/g fw. Quinic acid and 31 phenolic compounds were found in the rosehip extract of at least one cultivar. Results indicated ‘Aurora’ rosehips have potent antioxidant properties and a moderate inhibitory effect on acetylcholinesterase, highlighting their potential as a source of functional food. Additional research is needed to fully leverage these benefits and establish garden rosehips as a viable alternative to synthetic antioxidants. Full article

Specialized botanical gardens such as a rose garden, or rosarium, play a significant role due to their multifunctional nature surpassing simple gene bank assembly. Thus, this study conducted a detailed analysis of a rose garden through field and desk research, SWOT analysis, and ecosystem services assessment, aiming to determine the major strengths and opportunities, as well as weaknesses and threats that can promote or constrain the establishment of the first national rosarium in Serbia. After the analysis, the need for complete green area reconstruction arose to achieve both attractiveness and usefulness. Featuring old varieties, wild species, and companies’ own specific rose collections, the proposed garden has the potential to contribute major ecosystem services reflected in environmental, societal, and economic purposes. Owing to the uniqueness of the breeding program and collections created in the past decade, specific thematic parts—open field or greenhouse classroom, ‘roses under the glass bell’, abundant river flow, pollinators’ shelter, taste garden, and scent garden—are envisaged in the future exemplary rosarium that would not be only a classroom but a showroom for interested nurseries, small-scale functional food producers, flower shops, or amateur gardeners that would become aware of new cultivars and expand their marketing and utilization. Full article

Vase life directly affects the ornamental value of cut flowers, and extending vase life has been a research focus in the floriculture industry. The antioxidant and antimicrobial properties of Nano-Se provide a new direction to extend the life of cut-flower vase life. In order to explore the postharvest quality of Nano-Se on cut-flower roses, this study treated cut-flower roses with different concentrations of Nano-Se (200, 400, and 600 mM) using a commercially available preservative solution as a base solution. The results showed that appropriate concentrations of Nano-Se significantly increased the vase life of cut-flower roses and helped to maintain high petal moisture content. Nano-Se at concentrations of 200, 400, and 600 mM extended the vase life of cut roses by 4.3, 5.7, and 3.7 d, respectively. As the vase period extended, the Nano-Se treatment group effectively delayed the decline in antioxidant enzyme activities such as peroxidase (POD) and catalase (CAT), maintained the soluble sugar (SS) and soluble protein (SP) contents in the cut roses, and inhibited the production of malondialdehyde (MDA) and hydrogen peroxide (H₂O₂), reducing their accumulation. A correlation analysis of the physiological indexes of cut roses showed that vase life was positively correlated with POD and CAT activities, SS and SP contents, and total phenolic acid content and negatively correlated with MDA and H₂O₂ contents. This study provides a solid theoretical basis for the diversification of preservatives and the development of new preservatives for fresh-cut roses, which is expected to provide significant economic benefits. Full article

Ornamental plant breeding enables the selection of cultivars with desired features from numerous genotypes; however, this process is time-consuming and resource-demanding. Aiming to establish a pre-selection protocol that can facilitate the selection of dwarf rose varieties, the connection between anatomical and histological characteristics and the vegetative growth of rose cultivars was examined. To assess the adaptive potential of the studied cultivars, intra-annual cambial dynamics were explored relative to the observed meteorological fluctuations during the growing season. The investigation included six garden rose cultivars from the ‘Reka’ and ‘Pixie’ collections, bred under semi-arid open-field conditions in Serbia. Plant height ranged from 20 to 68 cm, with differing growth habits and types. Vegetative growth was significantly correlated with the xylem/phloem ratio, the proportion of total vessel area relative to cross-sectional and xylem areas, vessel-related features, and porosity (correlation coefficients up to 0.78). Regeneration via cambial activity and the formation of false rings were observed in five of the six cultivars studied, with meteorological analysis suggesting that precipitation and temperature triggered cambial reactivation. This approach effectively targets key parameters in the selection of dwarf and climate-resilient rose cultivars, facilitating the development of reliable pre-selection criteria. Full article

Propagation of cuttings is the primary method of rose multiplication. Aux/IAA, early response genes to auxin, play an important role in regulating the process of adventitious root formation in plants. However, systematic research on the identification of RhAux/IAA genes and their role in adventitious root formation in roses is lacking. In this study, 34 RhAux/IAA genes were identified by screening the rose genome, distributed on seven chromosomes, and classified into three clades based on the evolutionary tree. An analysis of the cis-acting elements in the promoters of RhAux/IAA genes revealed the presence of numerous elements related to plant hormones, the light signal response, the growth and development of plants, and abiotic stress. RNA-seq analysis identified a key RhIAA25 gene that may play an important role in the generation of adventitious roots in roses. Subcellular localization, yeast self-activation, and tissue-specific expression experiments indicated that RhIAA25 encoded a nuclear protein, had no yeast self-activated activity, and was highly expressed in the stem. The overexpression of RhIAA25 promoted the elongation of the primary root in Arabidopsis but inhibited adventitious root formation. This study systematically identified and analyzed the RhAux/IAA gene family and identified a key gene, RhIAA25, that regulates adventitious root generation in roses. This study offers a valuable genetic resource for investigating the regulatory mechanism of adventitious root formation in roses. Full article

Roses are increasingly being grown in soilless systems to increase productivity and reduce the challenges associated with soil-based cultivation. This study investigates the effects of using cocopeat and volcanic tuff substrates, the particle size of tuff, and substrate depth on the growth and flower quality of roses (Rosa hybrida L. cv. top secret) grown under greenhouse conditions. The treatments were cocopeat, tuff, cocopeat–tuff mixture, and tuff of particle size of 2 to 4 mm, 0 to 4 mm, and 0 to 8 mm at depths of 20 cm and 40 cm. The results showed that cocopeat had the highest water-holding capacity and photosynthetic rate. Tuff substrates had higher chlorophyll content throughout the growing season. Although flower numbers per plant in cocopeat and tuff from 0 to 8 mm at a depth of 20 cm were statistically similar, tuff from 0 to 8 mm had longer flowering stems and larger post-harvest flower diameters than cocopeat. An increase in the tuff depth from 20 to 40 cm decreased the flower number and main stem diameter. In conclusion, while cocopeat promotes rapid initial growth, volcanic tuff substrates, particularly tuff from 0 to 8 mm at a depth of 20 cm, provide long-term benefits for flower quality and plant health. Full article