Petunia Hybrida Research Articles

THE ARABIDOPSIS NHX1 GENE: OVEREXPRESSION AND ITS IMPACT ON SALT TOLERANCE IN TRANSGENIC PLANTS

Abiotic stresses, such as salinity, negatively impact crop growth, development and overall production. The discovery and operational confirmation of new genes will provide the framework for successful genetic engineering techniques to increase crop plants' resistance to salinity stress. The most effective method for maintaining ionic balance in plants under stress due to saltiness is provided by the membrane and vacuolar Na+/H+ counter transporter. The function of AtNHX1, the initially identified vacuolar antiporter from more advanced crops, was extensively researched. In this article, we will review the possible function of the Arabidopsis NHX1 gene that is responsible for salt tolerance and its transformation into Wheat, Barley, Poplar, Fescue, Petunia hybrid, Alfalfa & Soybean. Reason to engineer higher plants' genomes using Arabidopsis NHX1 genes to provide food sustainably in salinity-affected locations.

PhSPEAR1 Participates in Regulating the Branch Development of Petunia

Petunia hybrida is an economically important ornamental plant species. Branching in ornamental plants is closely associated with their ornamental traits, and branching is a significant agronomic trait in petunia, which shapes plant architecture and production cost. Although there are few studies regarding the involvement of the SPEAR genes in lateral branch development, they are known to regulate the development of plant organs. The PhSPEAR1 gene in petunia, an ortholog of Arabidopsis SPEAR1, was isolated for study. According to the results of real-time quantitative PCR (qRT-PCR), PhSPEAR1 was primarily expressed in the roots. The nucleus-specific fluorescence signal indicated that PhSPEAR1 was localized in the nucleus. An increase in PhSPEAR1 expression was induced by cytokinin or decapitation. Overexpression of PhSPEAR1 increased lateral branches in Arabidopsis. Based on our findings, PhSPEAR1 participates significantly in the regulation of branch number in petunia.

Myo-inositol oxygenase CgMIOX3 alleviates S-RNase-induced inhibition of incompatible pollen tubes in pummelo.

Pummelo (Citrus grandis L. Osbeck) exhibits S-RNase-based self-incompatibility (SI), during which S-RNase cytotoxicity inhibits pollen tubes in an S-haplotype specific manner. The entry of S-RNase into self-pollen tubes triggers a series of reactions. However, these reactions are still poorly understood in pummelo. In the present study, we used S-RNases as baits to screen a pummelo pollen cDNA library and characterized a myo-inositol oxygenase (CgMIOX3) that physically interacts with S-RNases. CgMIOX3 is highly expressed in pummelo pollen tubes and its down-regulation leads to a reduction in pollen tube growth. Upon entering pollen tubes, S-RNases increase the expression of CgMIOX3 and enhance its activity by directly binding to it in an S-haplotype-independent manner. CgMIOX3 improves pollen tube growth under oxidative stress through ascorbic acid accumulation and increases the length of self-pollen tubes. Furthermore, over-expression of CgMIOX3 increases the relative length of self-pollen tubes growing in the style of petunia (Petunia hybrida). This study provides intriguing insights into the pumelo SI system, revealing a regulatory mechanism mediated by CgMIOX3 that plays an important role in the resistance of pollen tubes to S-RNase cytotoxicity.

PhERF71 regulates petunia flower senescence by modulating ethylene biosynthesis

Ethylene, an endogenous hormone, commonly promotes flower senescence, but the molecular regulatory mechanisms underlying ethylene-induced flower senescence remain elusive. In this study, we describe an ethylene-responsive element binding factor, PhERF71, which affects flower senescence in petunia (Petunia hybrida). PhERF71 was up-regulated in senescing petunia flowers and after exogenous ethylene treatment, but silver thiosulfate (STS), an ethylene inhibitor, treatment decreased PhERF71 transcripts. Transient silencing of PhERF71 delayed petunia flower senescence, and reduced the transcription of senescence-associated gene 12 (PhSAG12). PhERF71-RNAi transgenic plants showed prolonged flower longevity, and PhERF71-overexpressing plants displayed shortened flower longevity, compared with wild-type (WT) plants. Electrolyte leakage rates and expression levels of PhSAG12 were lower in PhERF71-RNAi plants but higher in PhERF71-overexpressing plants. Silencing or overexpression of PhERF71 influenced the accumulation of ethylene, gibberellin (GA3), and abscisic acid (ABA), and the effect on ethylene accumulation was earlier than that on ABA and GA3. Ethylene treatment restored the delayed flower senescence to WT levels in PhERF71-silenced plants. Silencing of PhERF71 reduced expression levels of several ethylene biosynthetic genes, including 1-aminocyclopropane-1-carboxylic acid (ACC) synthase 4 (PhACS4), PhACS6, and ACC oxidase 4 (PhACO4), while overexpression of PhERF71 imposed the opposite effect on their expression levels. Dual luciferase assay showed that PhERF71 directly bound to the promoters of PhACS4 and PhACO4, and transient silencing of PhACS4 and PhACO4 delayed flower senescence. Our results suggest that PhERF71 is a positive regulator of flower senescence by promoting ethylene biosynthesis.

Investigation of Deficiency and Excess Nutrients Under in Vitro Culture Conditions in Petunia hybrida

Investigation of Deficiency and Excess Nutrients Under in Vitro Culture Conditions in Petunia hybrida

Overexpression of acdS in petunia reduces ethylene production and improves tolerance to heat stress.

Petunia hybrida, widely grown as a bedding plant, has reduced growth and flower quality at temperatures above 30 °C (heat stress), primarily due to heat stress-induced ethylene (ET) production. The gene acdS encodes the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCD) enzyme, which is known for its role in reducing ET production by breaking down the ET precursor, ACC, in plant tissues. This study investigated the impact of heat stress on both 'Mirage Rose' WT petunia and its acdS-overexpressing transgenic lines. Heat stress-induced growth inhibition was observed in WT plants but not in transgenic plants. The increased stress tolerance of transgenic plants over WT plants was associated with lower ET production, ROS accumulation, higher SPAD values, water content, and relative water content. Furthermore, higher sensitivity of the WT to heat stress than the transgenic plants was confirmed by analysing ET signalling genes, heat shock transcription factor genes, and antioxidant- and proline-related genes, more strongly induced in WT than in transgenic plants. Overall, this study suggests the potential application of acdS overexpression in other floriculture plants as a viable strategy for developing heat stress-tolerant varieties. This approach holds promise for advancing the floricultural industry by overcoming challenges related to heat-induced growth inhibition and loss of flower quality.

Evaluation of Particulate Matter Deposition Efficiency and Air Quality Improvement by Vertical Shrub and Climber Walls

Fine particulate matter poses a significant health risk indoors, making indoor air quality improvement crucial. Vertical greenery systems offer a promising solution, but selecting suitable plant species remains a challenge. This study evaluated the PM deposition and air quality impact of six ornamental plants (climbers and shrubs) in a controlled chamber. Almost all plants reduced CO2 by 20%, while PM deposition varied by species, with Petunia hybrid being the most efficient. Total leaf area showed the strong correlated with PM deposition. These findings confirm the potential of ornamental plants, particularly those with large total leaf area, for PM reduction in vertical greenery systems. Further research with a wider range of plants and advanced characterization techniques is needed to refine our understanding and develop practical guidelines for their effective use in indoor air purification.

Drought stress induces early flowering and the stress tolerance of offspring in Petunia hybrida.

Petunia hybrida (Solanaceae) exhibits high sensitivity to water scarcity, especially during flowering. This study investigated changes in the flowering time of P. hybrida in response to water deficit over a 7-week period. Various levels of water stress-i.e., light, moderate, and severe-were imposed on plants grown in a greenhouse, and these were compared to a control group grown alongside. Remarkably, early flowering was observed under severe stress in P. hybrida for the first time, occurring 5.3 days earlier than in the control group. Furthermore, seeds collected from control and treatment plants were then used to assess drought stress memory in offspring. Seedlings were cultivated in a dehydration medium containing either PEG 8000 or a control MS medium. In the PEG 8000 medium, seedlings from parents exposed to moderate and severe drought stresses exhibited higher drought tolerance than those from well-watered conditions. Moreover, they also displayed significantly longer roots, more leaves, and a lower ion leakage rate. Taken together, these findings demonstrated the presence of positive transgenerational effects on progeny. Thus, while parental drought stress during reproduction stage may affect seed quality, it can enhance drought tolerance in the next generation via induction of stress memory.

Dorsoventrally asymmetric expression of miR319/TCP generates dorsal-specific venation patterning in petunia corolla tube.

Vein-associated pigmentation (Venation) is a type of floral coloration adopted by plants to attract pollinators. Several petunia (Petunia hybrida) lines generate dorsoventrally asymmetric venation patterning of the corolla tube, in which venation is only presents in the dorsal tube. The molecular mechanism underlying this trait is unknown. Here, we demonstrate that miR319 is preferentially expressed in the dorsal corolla tube, leading to dorsoventrally asymmetric expression of its target genes. Transgenic lines overexpressing phy-miR319a generated uniform venation patterning of the corolla tube. Knockout of TCP genes targeted by miR319 promoted venation patterning in the ventral and dorsal tube, while overexpression of the miR319 target gene, PhTCP6, wholly inhibited corolla tube venation patterning. In addition, miR319-targeted TCPs negatively regulated venation patterning, likely by repressing the regulator of venation patterning, AN4. Together, our data demonstrate that asymmetric expression of miR319 promotes venation patterning in the petunia dorsal tube alone by repressing the expression of its target TCP genes, which negatively regulate corolla tube venation patterning. These findings provide novel insight into how the dorsoventrally asymmetric distribution of venation patterning is established in zygomorphic flowers.

Molecular characterization and pathogenicity of a novel monopartite geminivirus infecting tobacco in China

The occurrence of geminiviruses causes significant economic losses in many economically important crops. In this study, a novel geminivirus isolated from tobacco in Sichuan province of China, named tomato leaf curl Chuxiong virus (TLCCxV), was characterized by small RNA-based deep sequencing. The full-length of TLCCxV genome was determined to be 2744 nucleotides (nt) encoding six open reading frames. Phylogenetic and genome-wide pairwise identity analysis revealed that TLCCxV shared less than 91% identities with reported geminiviruses. A TLCCxV infectious clone was constructed and successfully infected Nicotiana benthamiana, N. tabacum, N. glutinosa, Solanum lycopersicum and Petunia hybrida plants. Furthermore, expression of the V2, C1 and C4 proteins through a potato virus X vector caused severe chlorosis or necrosis symptom in N. benthamiana. Taken together, we identified a new geminivirus in tobacco plants, and found that V2, C1 and C4 contribute to symptom development.

Silicon-Mediated Alleviation of Salinity Stress in Petunia (Petunia hybrida) by Modulation of Morphological, Physiological and Biochemical Indices

Silicon-Mediated Alleviation of Salinity Stress in Petunia (Petunia hybrida) by Modulation of Morphological, Physiological and Biochemical Indices

Comprehensive Analyses of Four PhNF-YC Genes from Petunia hybrida and Impacts on Flowering Time.

Nuclear Factor Y (NF-Y) is a class of heterotrimeric transcription factors composed of three subunits: NF-A, NF-YB, and NF-YC. NF-YC family members play crucial roles in various developmental processes, particularly in the regulation of flowering time. However, their functions in petunia remain poorly understood. In this study, we isolated four PhNF-YC genes from petunia and confirmed their subcellular localization in both the nucleus and cytoplasm. We analyzed the transcript abundance of all four PhNF-YC genes and found that PhNF-YC2 and PhNF-YC4 were highly expressed in apical buds and leaves, with their transcript levels decreasing before flower bud differentiation. Silencing PhNF-YC2 using VIGS resulted in a delayed flowering time and reduced chlorophyll content, while PhNF-YC4-silenced plants only exhibited a delayed flowering time. Furthermore, we detected the transcript abundance of flowering-related genes involved in different signaling pathways and found that PhCO, PhGI, PhFBP21, PhGA20ox4, and PhSPL9b were regulated by both PhNF-YC2 and PhNF-YC4. Additionally, the transcript abundance of PhSPL2, PhSPL3, and PhSPL4 increased only in PhNF-YC2-silenced plants. Overall, these results provide evidence that PhNF-YC2 and PhNF-YC4 negatively regulate flowering time in petunia by modulating a series of flowering-related genes.

Ac-DEVD-CHO (caspase-3/DEVDase inhibitor) suppresses self-incompatibility–induced programmed cell death in the pollen tubes of petunia (Petunia hybrida E. Vilm.)

Programmed cell death (PCD) is relevant to many aspects in the growth and development of a plant organism. In their reproduction, many flowering plant species possess self-incompatibility (SI), that is an intraspecific reproductive barrier, which is a genetic mechanism ensuring the avoidance of inbreeding depression by preventing self-pollination. This phenomenon enhances intraspecific variation; however, SI is rather a hindrance for some fruit plant species (such as plum, cherry, and peer trees) rather than an advantage in farming. PCD is a factor of the S-RNase–based SI in Petunia hybrida E. Vilm. The growth of self-incompatible pollen tubes (PTs) is arrested with an increase in the activity of caspase-like proteases during the first hours after pollination so that all traits of PCD—plasma membrane integrity damage, DNA degradation/disintegration, and damage of PT structural organization (absence of vacuoles, turgor disturbance, and separation of cell plasma membrane from the cell wall)—are observable by the moment of PT growth arrest. We succeeded in discovering an additional cytological PCD marker, namely, the formation of ricinosomes in self-incompatible PTs at early stages of PCD. SI is removable by treating petunia stigmas with Acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO), an inhibitor of caspase-3/DEVDase, 2 h before a self-incompatible pollination. In this process, the level of caspase-3-like protease activity was low, DNA degradation was absent, PTs grew to the ovary, fertilization was successful, and full-fledged seeds were formed.

Abscisic acid-induced transcription factor PsMYB306 negatively regulates tree peony bud dormancy release.

Bud dormancy is a crucial strategy for perennial plants to withstand adverse winter conditions. However, the regulatory mechanism of bud dormancy in tree peony (Paeonia suffruticosa) remains largely unknown. Here, we observed dramatically reduced and increased accumulation of abscisic acid (ABA) and bioactive gibberellins (GAs) GA1 and GA3, respectively, during bud endodormancy release of tree peony under prolonged chilling treatment. An Illumina RNA sequencing study was performed to identify potential genes involved in the bud endodormancy regulation in tree peony. Correlation matrix, principal component, and interaction network analyses identified a downregulated MYB transcription factor gene, PsMYB306, the expression of which positively correlated with 9-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (PsNCED3) expression. Protein modeling analysis revealed 4 residues within the R2R3 domain of PsMYB306 to possess DNA binding capability. Transcription of PsMYB306 was increased by ABA treatment. Overexpression of PsMYB306 in petunia (Petunia hybrida) inhibited seed germination and plant growth, concomitant with elevated ABA and decreased GA contents. Silencing of PsMYB306 accelerated cold-triggered tree peony bud burst and influenced the production of ABA and GAs and the expression of their biosynthetic genes. ABA application reduced bud dormancy release and transcription of ENT-KAURENOIC ACID OXIDASE 1 (PsKAO1), GA20-OXIDASE 1 (PsGA20ox1), and GA3-OXIDASE 1 (PsGA3ox1) associated with GA biosynthesis in PsMYB306-silenced buds. In vivo and in vitro binding assays confirmed that PsMYB306 specifically transactivated the promoter of PsNCED3. Silencing of PsNCED3 also promoted bud break and growth. Altogether, our findings suggest that PsMYB306 negatively modulates cold-induced bud endodormancy release by regulating ABA production.

Phase separation of S-RNase promotes self-incompatibility in Petunia hybrida.

Self-incompatibility (SI) is an intraspecific reproductive barrier widely present in angiosperms. The SI system with the broadest occurrence in angiosperms is based on an S-RNase linked to a cluster of multiple S-locus F-box (SLF) genes found in the Solanaceae, Plantaginaceae, Rosaceae, and Rutaceae. Recent studies reveal that non-self S-RNase is degraded by the Skip Cullin F-box (SCF)SLF-mediated ubiquitin-proteasome system in a collaborative manner in Petunia, but how self-RNase functions largely remains mysterious. Here, we show that S-RNases form S-RNase condensates (SRCs) in the self-pollen tube cytoplasm through phase separation and the disruption of SRC formation breaks SI in self-incompatible Petunia hybrida. We further find that the pistil SI factors of a small asparagine-rich protein HT-B and thioredoxin h together with a reduced state of the pollen tube all promote the expansion of SRCs, which then sequester several actin-binding proteins, including the actin polymerization factor PhABRACL, the actin polymerization activity of which is reduced by S-RNase in vitro. Meanwhile, we find that S-RNase variants lacking condensation ability fail to recruit PhABRACL and are unable to induce actin foci formation required for pollen tube growth inhibition. Taken together, our results demonstrate that phase separation of S-RNase promotes SI response in P. hybrida, revealing a new mode of S-RNase action.

Physiological roles of nano fertilizer and thiamine (B1) on some growth and flowering of Petunia plant (Petunia hybrida L.)

Physiological roles of nano fertilizer and thiamine (B1) on some growth and flowering of Petunia plant (Petunia hybrida L.)

Feasibility Study of Planting and Developing Atlas Plants (Petunia hybrida L.) and Chrysanthemums (Chrysanthemum morifolium L.) in Urban Streets of Karaj Considering the Effects of Light Pollution

Light pollution is the effect of inefficient and unnecessary artificial lighting in outdoor spaces. Each plant requires a certain amount of light for its life and photosynthesis processes to continue. Petunia, scientifically known as Petunia hybrida L., is an annual plant belonging to the Solanaceae family and is a short-day plant photo periodically. Chrysanthemum, scientifically known as Chrysanthemum morifolium L., belongs to the Asteraceae family and is a long-day plant photo periodically. These two plant species, Petunia and Chrysanthemum, which are planted in urban green spaces, were selected for the current study to determine the effects of nighttime light radiation. The present research was conducted during the year 1041 in the research greenhouse of Kharazmi University, Karaj campus, to investigate the effect of light pollution with 3 treatments: control, 44 lux, and 1344 lux, each replicated 3 times. Then, the results of morphological and physiological traits were examined. In Petunia, the results of the analysis of variance showed that most morphological traits of the light pollution treatment significantly differed from the control treatment, while no significant effect was observed for physiological traits. The 44-lux treatment had the most significant effect on plant height, root length, wet and dry stem weight, leaf surface area, chlorophyll a, chlorophyll b, total chlorophyll, and flavonoid. In Chrysanthemum, the analysis of variance results indicated that light pollution had a significant effect on some morphological traits. Overall, in this plant, stem and root length decreased compared to the control plant when light pollution was introduced. Overall, it can be concluded from the analysis of the data obtained from the experiment with a minimum of 3 replications using Duncan's multiple range test based on a completely randomized design that light pollution had a positive effect on Petunia (a long-day plant) at 44 lux. However, no specific effect was observed in Chrysanthemum (a short-day plant).

The Effect of Different Phosphorus Levels in Nutrient Solution on The Growth And Appearance Values of Petunia Plant (Petunia Hybrida Vilm)

The Effect of Different Phosphorus Levels in Nutrient Solution on The Growth And Appearance Values of Petunia Plant (Petunia Hybrida Vilm)

The effect of spraying with amino acids and iron on some characteristics of vegetative and flowering growth of petunia

A pot experiment was conducted during the 2019-2020 season at the temporary place of the Faculty of Agriculture/ University of Kufa/ Najaf city/ Iraq to estimate the response growth and flowering of petunia hybrid to Spraying amino acids and iron. The amino acid concentrations were 0, 3, and 6 ml.l-1, and three iron concentrations were 0, 15, and 30 mg.l-1.It is clear that the interaction between amino acid {6 ml.l-1}and iron {15mg.l-1} produces an increase in vegetative and flowering characters, the number of leaves and branches, length of flowering branches, number of flowers, Flower diameter, The age of the flower in the plant & the flower content of carotene pigment increased remarkably, while amino acid {6 ml.l-1} and iron {30 mg.l-1} have significant effect on leaf chlorophyll content, and total soluble carbohydrates. Keywords: Petunia plant; amino acids; Iron; Auxins; growth; flowering.

The Role of Reactive Oxygen Species in the In Vitro Germination and Growth of the Petunia (Petunia hybrida E. Vilm.) Male Gametophyte

The in vitro growth of the pollen tube (PT), an object of comprehensive and intensive research, is a model for studying the mechanisms of sexual reproduction in higher plants. We have studied the potential role of reactive oxygen species (ROS) in the in vitro germination and growth maintenance of the petunia (Petunia hybrida E. Vilm.) male gametophyte. The exogenous treatment with H2O2 influences the PT germination and polar growth in vitro. The addition of H2O2 to culture medium increases both the percentage of pollen grain germination and the PT length in the case of long cultivation, but inhibits both processes during the first hour of cultivation. This suggests that endogenous ROS play a decisive role in the early stages of pollen germination, with the sensitivity to endogenous ROS emerging later over the course of their growth. The addition of diphenylene iodonium chloride (DPI), a NADPH oxidase inhibitor, considerably decreases both the germination and the growth of the petunia male gametophyte at low concentrations (0.1 μM), and completely arrests the growth at high concentrations (1 μM). ROS are necessary for polar growth of the petunia male gametophyte; they are secreted in the early stages of pollen grain activation and are further localized to the initiation of the PT, mainly in the PT apical part, during polar growth, as confirmed with the help of intravital fluorescence microscopy.