Search Results (104)

The efficient production of high-quality bedding plants is essential for greenhouse growers aiming to meet market demands while minimising costs. This study investigated the effects of supplemental lighting (prolonged photoperiod) and retardant treatments on the growth, development, mineral composition, and flowering of vegetatively propagated Petunia × atkinsiana (Surfinia^® ‘Lime’ and ‘Purple’) and Calibrachoa × hybrida (Superbells^® ‘Unique Red’ and ‘Unique Golden Yellow’) cultivars. The plants were subjected to extended lighting for up to 16 h during the rooting phase and treated with or without a growth retardant. The supplemental light significantly accelerated the flowering, improved the shoot branching, and enhanced the mineral nutrient accumulation, particularly of calcium, sulphur, and magnesium. The illuminated plants also exhibited higher chlorophyll content and more favourable dry-mass accumulation. The growth retardants reduced the plant height and concentrations of nitrogen, phosphorus, and potassium but increased the calcium and magnesium contents. The combination of lighting and growth regulation optimised the plant morphology and nutritional status, producing compact, well-branched plants with enhanced visual appeal. Earlier flowering of illuminated plants is valuable from a commercial perspective, allowing earlier selling and improved product marketability. These findings confirm the synergistic benefits of early photoperiod control and chemical growth regulation in enhancing the commercial quality and sustainability of bedding plant production. Full article

Bradysia difformis Frey (Diptera: Sciaridae) is a fungus gnat that poses a significant threat to greenhouse cultures, and is attracted to soils devoid of peat. Fungal strains from the German Collection of Microorganisms and Cell Culture (DSMZ), such as Beauveria bassiana, Metarhizium flavoviride, Mucor hiemalis, and Niesslia tinuis, as well as Serendipita indica, were screened for entomopathogenic activity against B. difformis and their capacity to colonize Petunia hybrida cv. “Mitchell” and Ocimum basilicum plants. The survival rates of Bradysia difformis (three instar larvae) treated with Metarhizium flavoviride were 45.33% at 14 days following inoculation with 1 × 10⁶ spores/mL of each fungal strain, when compared to others. We concluded that the fungal strain M. flavoviride could serve as an entomopathogenic fungus with the highest virulence against B. difformis larvae. Although M. flavoviride did not show a beneficial effect as an endophyte, interestingly, the strain Niesslia tinuis exhibited plant growth benefits in Petunia hybrida cv. “Mitchell” by enhancing its shoot length up to 13.18 ± 0.72 cm, whereas the control treatment had a shoot length up to 10.68 ± 0.39. Enzymatic assays confirmed the ability of M. flavoviride to produce cuticle-degrading enzymes such as chitinase and protease. Together, these findings highlight the potential of EMPF—particularly M. flavoviride—as a sustainable biocontrol tool well-suited for peat-free horticultural systems, offering an eco-friendly alternative to chemical insecticides where fungus gnat pressure is typically high. Full article

The SEPALLATA3 (SEP3)-like MADS-box genes play crucial roles in determining petal identity and development in the petunia and tomato of Solanaceae. Solanum nigrum is a self-pollinating plant in the Solanaceae family, and produces white flowers. However, the mechanisms controlling the transition from green to white petals during flower development remain poorly understood. In this study, we isolated a flower-specific SEP3-like gene, SnMADS37, from S. nigrum, and investigated its potential role in chlorophyll metabolism during petal development. Our results show that quantitative RT-PCR analysis demonstrates that SnMADS37 is exclusively expressed in petals and stamens during early floral bud development. Overexpression of SnMADS37 clearly enhanced the number of petals, promoting the formation of additional petal-like tissues in stamens and extra organs in some fruits. Moreover, fully opened transformed petals exhibited notable chlorophyll accumulation at their tips and veins, whereas silencing of Snmads37 clearly inhibited petal expansion and reduced green pigmentation in early flower buds. Additionally, the transformed green petals exhibited distinct conical epidermal cells in the green regions, similar to wild type (WT) petals. Our results demonstrate that SnMADS37 plays a critical role in regulating petal identity, expansion, and chlorophyll metabolism during petal development. These findings provide new insights into the functional diversification of SEP3-like MADS-box genes in angiosperms. Full article

Trehalose is a nonreducing disaccharide critical for cellular integrity and stress adaptation in plants, and its synthesis relies on trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphate phosphatase (TPP). Despite their established roles in abiotic stress responses across model plants, these gene families remain underexplored in ornamental species like Petunia hybrida. Here, TPS and TPP genes in two wild petunia progenitors, P. axillaris and P. inflata, underwent a genome-wide analysis, with 10 TPS and 8–9 TPP genes being identified in each species. According to phylogenetic analysis, petunia TPS proteins cluster into two clades, while TPP proteins were classified into three clades, showing closer evolutionary ties to tomato homologs. Cis-acting elements profiling identified hormone- and stress-responsive regulatory elements (e.g., ABRE, TC-rich repeats). Expression analysis under drought, heat, and salt stress revealed dynamic temporal regulation. For instance, PaTPS4/PaTPS9 were early responders (peak at 6 h) under drought and salt stress, while PaTPS8 exhibited sustained upregulation during salt treatment. Heat stress uniquely suppressed PaTPS1,2 and PaTPP1, contrasting with broad upregulation of other members. Notably, PaTPP3 displayed delayed induction under heat. These findings underscore the functional diversity within TPS/TPP families, with specific members governing stress-specific responses. This study provides a foundational resource for leveraging these genes to enhance stress resilience and ornamental value in petunia. Full article

The biological role of the fluorescence of flowers is a matter of debate. Anthocyanins are a group of compounds that are weakly fluorescent; their fluorescence in flowers has been rarely studied. This study aimed to compare the absorption and fluorescence spectra of anthocyanins extracted from several anthocyanin-containing autumn flowers and examine changes in these spectra during the storage of petals at cold-room and room temperatures and during the storage of dried petals. Petals of red clover Trifolium pratense, pink petunia Petunia × hybrida, Pelargonium horatum, Pelargonium. zonale, Pelargonium. peltatum, red and pink Begonia semperflorens, Buddleja japonica, and purple Chrysanthemum were studied. The results demonstrate that it is possible to distinguish between petals of various flowers based on the absorption spectra of petal extracts and the fluorescence spectra of petal extracts and intact petals. Spectral changes during storage were not always unidirectional and progressive; the most common one was the increase in the intensity of the fluorescence band at 500–560 nm at the excitation wavelength of 460 nm. These results point to the possibility of using fluorescence measurements to identify and estimate the freshness of petal-based material in herbalism, forensic analysis, and the food industry. The measurement of the spectra of whole petals or their fragments by front-face fluorimetry, including common plate readers, may be especially useful due to its simplicity and rapidity. Full article

Many plant groups exhibit complex evolutionary processes, including hybridization, incomplete lineage sorting, and variable evolutionary rates, which make species delimitation challenging. Molecular data have been essential for studying such groups, including Petunia, where local adaptation, allopatric speciation, pollinator interactions, and hybridization shape diversity and population structure. In this study, we produced the first broadly inclusive phylogenetic tree of Petunia using high-throughput DNA sequence data generated by genome complexity reduction-based sequencing (DArT), and incorporating all currently accepted taxa. Additionally, we reviewed previously published phylogenetic and phylogeographic studies on these species to support the taxonomic revision. Phylogenetic analyses based on SNPs were largely congruent, revealing two well-supported clades divided by corolla tube length, consistent with previous studies. These clades likely originated and diversified during the Pleistocene. The phylogenetic trees provided strong support for taxonomic changes, resolving long-standing uncertainties. We recognize P. axillaris, P. parodii, and P. subandina as independent species, elevate P. integrifolia subsp. depauperata to P. dichotoma Sendtn., and resurrect P. guarapuavensis. Additionally, our results highlighted unsolved questions regarding the evolutionary history of the short corolla tube clade, suggesting the need for further investigation into its diversification and genetic structure. Full article

The double-flower trait is highly valued in ornamental plants due to its unique aesthetic appeal, yet its genetic basis varies significantly across different species. While AGAMOUS (AG) and APETALA2 (AP2)-like genes have been demonstrated to play crucial roles in floral organ identity regulation in the model plant Arabidopsis thaliana, the underlying mechanisms governing double-flower formation in many ornamental species remain largely unexplored. In this study, we examined the inheritance pattern of this trait and identified a genetic variant associated with petal number variation. Crosses between the single-flowered cultivar ‘Baccarat White’ (BW) and the semi-double cultivar ‘Duo Lavender’ (DL) produced a 1:1 segregation of single and semi-double flowers in the F1 generation, while self-pollination of DL yielded a 1:2:1 segregation of single, semi-double, and double flowers. These results indicate that the double-flower trait follows a single-gene, semi-dominant inheritance model. Whole-genome sequencing of BW and DL followed by sequence analysis of floral organ identity genes revealed no significant differences in B-class (PhGLO1, PhGLO2, PhDEF, and PhTM6) or C-class (pMADS3 and FBP6) genes between the two cultivars. Notably, a 10 kb insertion upstream of the miR172 target site in the PhBOB gene was detected in DL. PCR genotyping of 192 F1 progenies demonstrated complete co-segregation between this insertion and the double-flower phenotype, suggesting a strong genetic association. Moreover, qRT-PCR analysis showed that PhBOB expression was significantly elevated in DL—exhibiting a 69-fold increase in petals compared to BW—implying that its overexpression disrupts the petal-to-stamen identity transition. Additionally, another AP2 family gene, PhROB3, was upregulated in semi-double flowers, with a 10-fold higher expression in the petals and stamens of DL relative to BW, suggesting its potential role in floral organ differentiation. This study elucidates the molecular regulatory mechanism underlying the double-flower trait in petunia, highlighting the role of PhBOB in floral organ identity specification and providing new insights into the potential function of PhROB3 in double-flower development. Full article

Gastrointestinal parasites have been reported to have negative effects on chickens reared in rural areas in African countries. Hence, smallholder farmers use ethnoveterinary remedies to control these parasites in village chickens. This study used online databases (ScienceDirect, PubMed, and Google Scholar) to search, gather, and review articles published between January 1990 and June 2024 where ethnoveterinary intervention was considered to control gastrointestinal parasites, following PRISMA guidelines. A total of 540 articles were generated, and only 17 articles passed the screening process and were considered for further analysis. The findings of this review indicate that ethnoveterinary remedies are used by smallholder farmers to control gastrointestinal parasites such as Ascaridia galli, Capillaria spp., Choanotaenia infundibulum, Eimeria spp., Heterakis gallinarum, and Raillietina cesticillus in village chickens. Aloe spp., Carica papaya, Musa paradisiaca, and Venonia amygdalina were reported as the most-preferred medicines, and farmers utilized different plant parts ranging from leaves (48.8%), bark and roots (12.2%), tubers (7.3%), and seeds (4.9%). These remedies are administered per os, topically, and dermally. The current review successfully summarized ethnoveterinary intervention used by smallholder farmers to control gastrointestinal parasites in chickens found in African countries. Therefore, there is a need to investigate the efficacy of these identified ethnoveterinary medicines against gastrointestinal parasites in chickens. Full article

Western flower thrips (WFT), Frankliniella occidentalis (Pergande) [Thysanoptera: Thripidae], is a destructive pest of greenhouse ornamentals. Flowering yellow marigolds, Tagetes patula (L.) [Asterales: Asteraceae], have been shown to be attractive to WFT, implicating their suitability as a trap plant. However, functionality may vary in part due to crop variety, the growth stage of the crop in which the marigold trap plant is deployed and whether or not the crop plants have flowers present. The attractiveness of yellow marigolds was tested within several varieties of mature, flowering ornamental bedding plants that were flowering or had their flowers removed: Calibrachoa spp. Petunia spp. Verbena spp., Osteospermum spp., Impatiens haekeri and other marigolds. Trials were conducted in cages under controlled greenhouse conditions for six weeks. The effectiveness of orange vs. yellow marigolds as a trap plant was also assessed. The results showed that WFT were attracted to flowering marigolds and, over time, were present in greater numbers on these than crop plants for all crop species and varieties tested at varying levels of significance. Yellow marigold trap plants were the least effective when deployed within other marigold varieties. In crops with flowers, it took up to five weeks for the number of WFT on trap plants to surpass numbers on crop plants. In contrast, in crop varieties with their flowers removed, trap plants attracted WFT earlier, within one to two weeks, and harbored them in greater numbers over time. Orange, flowering marigolds were a less effective trap plant compared to yellow marigolds. These results confirm that flowering yellow marigolds are attractive to WFT and have potential as a trap plant in greenhouse ornamentals, particularly when crop plants do not have flowers. 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

The potential role of reactive oxygen species (ROS) is studied in the male gametophytes of petunia (Petunia hybrida E. Vilm.) grown in vivo with a focus on its germination, growth support in the progamic stage of fertilization, and the function of the mechanism underlying S-RNase-based self-incompatibility. Exogenous treatment with H₂O₂ influences the in vivo germination and polar growth of pollen tubes (PTs), which manifests as the acceleration or inhibition of these processes depending on its concentration, time interval after pollination, and pollination variant. The H₂O₂ treatment of the stigma somewhat stimulates the PT elongation in the late stages of self-incompatible pollination (4–8 h) versus the strong PT inhibition observed during the first hour of germination. A different pattern is observable in cross-compatible pollination: the H₂O₂ treatment of pistils inhibits PT growth during the overall pollination at all tested concentrations. Treatment of pistils with the NADPH oxidase inhibitor diphenylene iodonium chloride (DPI) strongly inhibited the growth of PTs in both pollination variants. In addition, DCF-DA staining confirms that ROS are formed in pollen, PTs, stigma of nonpollinated pistil, and the pistil itself in all pollination variants. The PT growth during the function of the self-incompatibility mechanism is arrested at high ROS concentrations, which is presumably associated with the SI-induced programmed cell death. Our results demonstrate that ROS are a necessary component of pollen, PTs, exudate, and stigma cells and contribute to successful reproduction. This study provides a deeper insight into the ROS functions during the PT growth in an in vivo system. Full article

Iron (Fe) is an essential micronutrient for plants. Due to the low Fe bioavailability in cultivated soils, Fe deficiency is a widespread agricultural problem. In this study, we present the functional characterization of a petunia (Petunia hybrida) basic-helix-loop-helix transcription factor PhbHLH121 in response to Fe shortage. Real-time PCR revealed that the expression of PhbHLH121 in petunia roots and shoots was downregulated under Fe-limited conditions. CRISPR/Cas9-edited phbhlh121 mutant plants were generated to investigate the functions of PhbHLH121 in petunia. Loss-of-function of PhbHLH121 enhanced petunia tolerance to Fe deficiency. Further investigations revealed that the expression level of several structural genes involved in Fe uptake in petunia, such as IRT1 and FRO2, was higher in phbhlh121 mutants compared to that in wild-type under Fe-limited conditions, and the expression level of several genes involved in Fe storage and Fe transport, such as VTL2, FERs and ZIF1, was lower in phbhlh121 mutants compared to that in wild-type under Fe-deficient conditions. Yeast one-hybrid assays revealed that PhbHLH121 binds to the G-box element in the promoter of genes involved in Fe homeostasis. Yeast two-hybrid assays revealed that PhbHLH121 interacts with petunia bHLH IVc proteins. Taken together, PhbHLH121 plays an important role in the Fe deficiency response in petunia. Full article

The ARF gene family plays a vital role in regulating multiple aspects of plant growth and development. However, detailed research on the role of the ARF family in regulating flower development in petunia and other plants remains limited. This study investigates the distinct roles of PhARF5 and PhARF19a in Petunia hybrida flower development. Phylogenetic analysis identified 29 PhARFs, which were grouped into four clades. VIGS-mediated silencing of PhARF5 and PhARF19a led to notable phenotypic changes, highlighting their non-redundant functions. PhARF5 silencing resulted in reduced petal number and limb abnormalities, while PhARF19a silencing disrupted corolla tube formation and orientation. Both genes showed high expression in the roots, leaves, and corollas, with nuclear localization. The transcriptomic analysis revealed significant overlaps in DEGs between PhARF5 and PhARF19a silencing, indicating shared pathways in hormone metabolism, signal transduction, and stress responses. Phytohormone analysis confirmed their broad impact on phytohormone biosynthesis, suggesting involvement in complex feedback mechanisms. Silencing PhARF5 and PhARF19a led to differential transcription of numerous genes related to hormone signaling pathways beyond auxin signaling, indicating their direct or indirect crosstalk with other phytohormones. However, significant differences in the regulation of these signaling pathways were observed between PhARF5 and PhARF19a. These findings reveal the roles of ARF genes in regulating petunia flower development, as well as the phylogenetic distribution of the PhARFs involved in this process. This study provides a valuable reference for molecular breeding aimed at improving floral traits in the petunia genus and related species. Full article

Petunia stands as the top-selling bedding plant in the U.S., and improved lighting control in greenhouses holds the potential to reduce crop production time and optimize crop quality. This study investigated the impact of four distinct daily light integral (DLI) conditions with and without supplemental far-red (FR) radiation on the growth of petunia liners and subsequent development of finish plants. Two experiments were conducted in spring (9 April to 18 June 2021) and winter (28 October 2021 to 6 January 2022). Petunia cuttings were rooted in a common environment and then transferred to four greenhouse sections with different DLI treatments: 6, 9, 12, and 15 mol·m⁻²·d⁻¹ for four weeks. Within each DLI condition, half of the plants were exposed to 28 μmol·m⁻²·s⁻¹ supplemental FR radiation for 16 h daily (equivalent to 1.61 mol·m⁻²·d⁻¹ light integral). The number of flower buds and open flowers were tracked daily. Representative liners were destructively harvested and evaluated after four weeks of lighting treatments. The remaining plants were transplanted and moved to a common DLI condition of 15 mol·m⁻²·d⁻¹ for an additional three weeks before being destructively harvested and evaluated as finish plants. The primary finding reveals the promoting effect of DLI on flowering, branching, morphology, and biomass accumulation of petunia liners, with many effects persisting into the finish stage. A threshold DLI of 9 mol·m⁻²·d⁻¹ was identified, as lower DLI (6 mol·m⁻²·d⁻¹) resulted in extensive stem elongation, rendering the plants unmarketable. Higher DLI levels were found to be optimal in terms of flowering and morphology. Supplemental FR accelerated flowering by up to three days in the summer experiment and up to 12 days in the winter experiment. However, FR had limited impact on the number of flower buds and open flowers, branching, and shoot and root weight of the finish plants. Interactions between DLI and FR were observed on some parameters, whereby FR effects were more pronounced under lower DLI. Overall, both higher DLI and supplemental FR exhibited beneficial effects, but DLI had a more pronounced effect. Thus, DLI during petunia liner production appears more important than adding FR. This study well simulated the commercial propagation and production of petunia plants, providing practical insights for decision-making regarding lighting strategies. Full article

Osmanthus fragrans, a native to China, is renowned as a highly popular gardening plant. However, this plant faces significant challenges from drought stress, which can adversely affect its flowering. In this study, we found that the plasma membrane-localized gene OfPIP2 exhibited a substantial upregulation during the flowering stages and in response to drought stress. GUS staining has illustrated that the OfPIP2 promoter can drive GUS activity under drought conditions. The overexpression of OfPIP2 was found to enhance petal size by modulating epidermal cell dimensions in Petunia and tobacco. Moreover, this overexpression also bolstered drought tolerance, as evidenced by a reduction in stomatal aperture in both species. Furthermore, yeast one-hybrid (Y1H) and dual-luciferase (Dual-LUC) assays have indicated that the transcription factor OfMYB28 directly binds to the OfPIP2 promoter, thereby regulating its expression. Together, we speculated that a module of OfMYB28-OfPIP2 was not only involved in the enhancement of petal size but also conferred the improvement of drought tolerance in O. fragrans. These results contribute valuable insights into the molecular function of the OfPIP2 gene and lay a foundation for molecular breeding strategies in O. fragrans. Full article