Cut Carnation Flowers Research Articles

Preservation of cut carnation flowers using non-polar gas.

Preservation of cut carnation flowers using non-polar gas.

ANTAGONIZING EFFECTS OF (I) VOLATILES, AND (II) WATER SOLUBLE CYCLOPROPENE DERIVATES ON ETHYLENE ACTION

The potency of 12 new volatile cyclopropenes to inhibit ethylene action synthesized at the laboratory of Edward C. Sisler was assessed. The inhibitory effect was evaluated in the following test systems: ethylene-induced ripening of climacteric fruits, ethylene-induced growth modifications in etiolated pea seedlings and abscission of citrus leaf explants. In some of the test systems, the new compounds were found to be more potent ethylene antagonists than 1-MCP, whereas in other systems they were less potent. A novel water soluble inhibitor of ethylene action 3-(cycloprop-1-enylpropanoic acid, sodium salt (CPAS, IL patent application 184729, WO 2009/010981 A1)), was synthesized by D-Pharm, Israel, from one of the new cyclopropene derivatives. CPAS was found to counteract ethylene-induced abscission of citrus leaf explants and of avocado fruit peduncles, to inhibit ethylene-induced leaf epinasty in tomato seedlings, and to prolong the vase-life of carnation and petunia cut flowers. It also considerably delayed fruit ripening processes, such as skin colour change in 'Hass' avocado and banana fruit and softening of peach fruit. Banana and avocado fruit softening were delayed by CPAS to a lesser extent, probably due to insufficient penetration.

Crecimiento en clavel estándar cv. Nelson, en suelo y en sustratos

El cultivo de clavel en la sabana de Bogotá ha sido importante, ya que representa en la actualidad el segundo lugar de exportación en flores de corte. Recientemente, su producción en sistema de cultivo en sustrato ha aumentado debido fundamentalmente a limitantes de tipo sanitario, por lo cual es importante el estudio del crecimiento de las plantas establecidas en este sistema de cultivo. El objetivo de este estudio fue evaluar el crecimiento del clavel estándar cv. Nelson establecido en sustratos y en suelo, a segundo pico de cosecha, para lo cual, en el SENA - Centro Multisectorial de Mosquera, plantas de clavel se sometieron a los siguientes tratamientos: 100% de cascarilla de arroz quemada; 65% cascarilla de arroz quemada - 35% fibra de coco; 35% cascarilla de arroz quemada - 65% fibra de coco y suelo. En muestreos continuos se evaluaron las variables número de hojas, longitud del tallo, diámetro de tallo, número de nudos y diámetro y longitud del botón floral y se ajustaron curvas de crecimiento. Las plantas cultivadas en el tratamiento suelo presentaron mayor número de tallos. En este tratamiento los tallos florales también presentaron un mayor número de nudos y de hojas; sin embargo, fueron más cortos. Así mismo, presentaron menor diámetro de tallo y menor longitud y diámetro del botón floral; características determinantes de la calidad. Por tanto, la producción de tallos exportables de grado "select" fue significativamente inferior en el tratamiento suelo, en comparación con los demás tratamientos.

EFFECTS OF POSTHARVEST NANO-SILVER TREATMENTS ON CUT-FLOWERS

Nano-silver (NS) is nanometer sized (similar to 2-5 nm) silver (Ag+) particles used in other applications as an antimicrobial material. A series of experiments were conducted to investigate effects of pulse and vase solution treatments with NS solutions on the vase lives of commercially important rose (Rosa hybrida), carnation (Dianthus caryophyllus) and gerbera (Gerbera jamesonii) cut-flowers. Both pulse and vase solutions treatments with NS individually and/or in combination extended the vase lives of these three species. Moreover, NS treatments in combination with sugar further prolonged the vase lives of these cut-flowers. In vitro tests and microscope observations indicated that NS treatments inhibited the growth of microorganisms from cut carnation flower vase solution.

Effect of Exogenous Adenosine Triphosphate Supply on the Senescence-related Physiology of Cut Carnation Flowers

Effect of Exogenous Adenosine Triphosphate Supply on the Senescence-related Physiology of Cut Carnation Flowers

THIDIAZURON EFFECTS ON DIANTHUS CARYOPHYLLUS 'LUNETTA'

Experiments were conducted to determine the effects of Thidiazuron (TDZ) applied preharvest under glasshouse conditions on Dianthus caryophyllus 'Lunetta'. Thidiazuron at 0, 1, 10, 100, and 1000 mu M was applied as a foliar spray in two separate experiments. 15 plants were used for each concentration in both experiments. Experiments were arranged in completely randomized designs. Time to flowering was recorded, and relative stem length, total nitrogen, and tissue water content were measured at harvest. Postharvest vase life, relative fresh weight changes, and solution uptake changes were also measured. TDZ treatments sometimes decreased relative stem length compared to the control (0 mu M). TDZ treatment tended to decrease total nitrogen and water content of tissues slightly, but not significantly (P > 0.05). In the first experiment, TDZ at 100 mu M significantly increased the vase life of cut carnation flowers compared to the control. In the second experiment, TDZ applied preharvest at both 10 and 100 mu M significantly increased their vase life. TDZ treated flowers tended to maintain higher relative fresh weight, with positive differences for the 100 mu M TDZ treatment being apparent at days 5, 7 and 9 of vase life. Solution uptake was sometimes higher in TDZ treated flowers.

Differential Expressions of Expansin and Xyloglucan Endotransglucosylase Genes by Adenosine Triphosphate of Cut Carnation Flowers During Senescence

Differential Expressions of Expansin and Xyloglucan Endotransglucosylase Genes by Adenosine Triphosphate of Cut Carnation Flowers During Senescence

Depression of enzyme activities and gene expression of ACC synthase and ACC oxidase in cut carnation flowers under high-temperature conditions

High-temperature depression of ethylene production in cut carnation flowers cv. ‘Excerea’ can occur because of inhibition of ACC synthase (ACS) and ACC oxidase (ACO) activities in flowers. Large differences were apparent between ACS activity in petals at 24°C and 32°C. These ACC-accumulation-related activities were markedly decreased in petals at 32°C, indicating that a low ACS activity and ACC accumulation in petals are a factor of ethylene biosynthesis inhibition under high-temperature conditions. In addition, the respective expressions of DC-ACO1 and DC-ACS1 were low in both gynoecia and petals of flowers kept at 32°C. Results indicate that low ACS and ACO activities under high-temperature conditions were transcriptionally regulated.

Sucrose prevents up-regulation of senescence-associated genes in carnation petals

cDNA microarrays were used to characterize senescence-associated gene expression in petals of cut carnation (Dianthus caryophyllus) flowers, sampled from anthesis to the first senescence symptoms. The population of PCR fragments spotted on these microarrays was enriched for flower-specific and senescence-specific genes, using subtractive hybridization. About 90% of the transcripts showed a large increase in quantity, approximately 25% transiently, and about 65% throughout the 7 d experiment. Treatment with silver thiosulphate (STS), which blocks the ethylene receptor and prevented the normal senescence symptoms, prevented the up-regulation of almost all of these genes. Sucrose treatment also considerably delayed visible senescence. Its effect on gene expression was very similar to that of STS, suggesting that soluble sugars act as a repressor of ethylene signal transduction. Two fragments that encoded a carnation EIN3-like (EIL) protein were isolated, some of which are key transcription factors that control ethylene response genes. One of these (Dc-EIL3) was up-regulated during senescence. Its up-regulation was delayed by STS and prevented by sucrose. Sucrose, therefore, seems to repress ethylene signalling, in part, by preventing up-regulation of Dc-EIL3. Some other transcription factors displayed an early increase in transcript abundance: a MYB-like DNA binding protein, a MYC protein, a MADS-box factor, and a zinc finger protein. Genes suggesting a role in senescence of hormones other than ethylene encoded an Aux/IAA protein, which regulate transcription of auxin-induced genes, and a cytokinin oxidase/dehydrogenase, which degrades cytokinin. Taken together, the results suggest a master switch during senescence, controlling the co-ordinated up-regulation of numerous ethylene response genes. Dc-EIL3 might be (part of) this master switch.

Changes in pigment content and surface micro-morphology of in cut carnation flower petals under high-temperature conditions

SummarySenescence of carnation petals progresses gradually, even when climacteric ethylene production is blocked. The most distinct visible changes in the later stages of petal senescence are a fading of flower colour and a change in appearance (“freshness”). Cut carnation cv. Excerea flowers treated with silver thiosulphate were kept in vase solutions with or without 1% (w/v) sucrose under high-temperature conditions (32ºC). Changes in pigment content and the micro-morphology of epidermal cells in petals were monitored. The main pigment in ‘Excerea’ carnation petals was pelargonidin-3-malylglucoside (Pg3MG). A 48 – 70% reduction in Pg3MG occurred between day-5 and day-15 in petals kept under high-temperature conditions. Petal colour changes, as determined by lower C* and hº values using a colourimeter, were consistent with the reduction in Pg3MG content. Sucrose [1% (w/v)] in the vase water was effective at inhibiting the reduction in pigment content in petals kept under high-temperature conditions. An enlargement of epidermal cells occurred on both the abaxial and adaxial surfaces of petals between day-5 and day-15, irrespective of petal position, temperature conditions, or the composition of the vase solution. This enlargement in epidermal cells could cause the change in appearance of the flowers.

The role of N-lauroylethanolamine in the regulation of senescence of cut carnations ( Dianthus caryophyllus)

N-acylethanolamines (NAEs) are a group of lipid mediators that play important roles in mammals, but not much is known about their precise function in plants. In this work, we analyzed the possible involvement of N-lauroylethanolamine [NAE(12:0)] in the regulation of cut-flower senescence. In cut carnation flowers of cv. Red Barbara, the pulse treatment with 5 microM NAE(12:0) slowed senescence by delaying the onset of initial wilting. Ion leakage, which is a reliable indicator of membrane integrity, was postponed in NAE(12:0)-treated flowers. The lipid peroxidation increased in carnation petals with time, in parallel to the development in activity of lipoxygenase and superoxide anion production rate, and these increases were both delayed by NAE(12:0) supplementation. The activities of four enzymes (superoxide dismutase, catalase, glutathione reductase and ascorbate peroxidase) that are implicated in antioxidant defense were also upregulated in the cut carnations that had been treated with NAE(12:0). These data indicate that NAE(12:0)-induced delays in cut-carnation senescence involve the protection of the integrity of membranes via suppressing oxidative damage and enhancing antioxidant defense. We propose that the stage from the end of blooming to the onset of wilting is a critical period for NAE(12:0) action.

Exogenous spermidine delays senescence of Dianthus caryophyllus flowers

Cut carnation flowers, cv. Rieko, were held under standard environmental conditions and treated with different concentrations of spermidine (spd), either by spraying directly on the petals or by supplying it in the water of the vase. The greatest delay of senescence was obtained with 10 mM spd in the water of the vase (10 mM spd-V) while no significant delay of senescence was produced by spraying the flowers. Polyamine levels (free, PCA-soluble and PCA-insoluble conjugated) were determined in control and 10 mM spd-V-treated flowers. Starting from day 3, spermidine was absorbed from the watering solution and accumulated in the petals both in the free and PCA-soluble fractions. Putrescine levels also increased with 10 mM spd-V treatment. Total anthocyanin, RNA, DNA, protein content and protease activity were determined over 10 days in control and 10 mM spd-V-supplied flowers. Spermidine was shown to stabilize and retard the degradation of DNA.

Effects of adenosine triphosphate on the vase life of cut carnation flowers

The addition of adenosine triphosphate (ATP) to vase solutions at a concentration of 0.01−0.50 mmol/L markedly extended the vase life of cut carnation flowers at 25°C and 80−90% relative humidity. The most beneficial effect on vase life was observed at 0.1 mmol/L ATP, with a 28% extension over non-ATP-treated flowers. Furthermore, the addition of ATP at 0.1 mmol/L increased flower size by 12% by the end of the vase-holding period and significantly extended the time to maximum flower expansion by 1.7 days, compared with non-ATP-treated flowers held in distilled water. Our data suggest that exogenous ATP supply is an effective method to extend the vase life of cut carnation flowers.

A method for determining the vase life of cut spray carnation flowers.

Cut flowers of carnation are classified into two types, the standard type with one flower on a stem and the spray type with multiple flowers on a stem. The vase life of carnation flowers has been generally determined by observing senescence profiles, i.e., in-rolling of petal margin and wilting of whole petals as well as ethylene production. In the present study, we tried to determine the vase life of spray type carnation flowers by observing the number of open flowers, i.e., the percentage of open flowers to the total number of initial flower buds. The vase life determined by this method was similar to that determined by the former method, and was useful to evaluate the action of preservatives on carnation flowers.

HIGH-CONTRAST NEUTRON IMAGING TO OBSERVE WATER DISTRIBUTION IN INTACT PLANTS

Low energy neutron radiography has good contrast with respect to water concentration when tested with a several plant materials. Therefore, this method is suitable for detection of small changes in water distribution in intact plants. In this study, low energy neutron beams of cold neutron (CN) and very cold neutron (VCN) ports at Kyoto University Reactor (KUR), and the VCN port at Institute of Laue-Langevin (ILL) reactor were used respectively. Low energy neutron radiography images were obtained with a cooled CCD camera system and an imaging plate. Using low energy beams at the ILL reactor, relatively small water changes in thin leaves during rehydration were observed. The transmission thickness was limited because of the low energy. From the computed tomographic (CT) images of cut carnation flowers obtained using beams from the VCN port at KUR it was observed that the calyx diameter was about 10mm. The total time to construct a CT image composed of 180 2D images was 3.5 h.

CHANGES IN WATER DISTRIBUTION DURING SENESCENCE IN CUT CARNATION FLOWERS

Neutron radiographic methods are suitable for obtaining images of water distribution in intact plants. When a neutron beam irradiates a plant sample, the number of neutrons penetrating the sample decreases with the number of hydrogen atoms in the sample. Generally, plants contain more than 80% water, so a neutron image of a plant is approximately equivalent to its water distribution. In this study, the senescence of cut carnation flowers was observed using thermal neutron (TN) radiography and very cold neutron (VCN) radiography. A CCD-cooled camera intermittently photographed neutron images during neutron irradiation. To evaluate the advancement of senescence, carbon dioxide production from a flower placed in a gas-tight container was measured using a CO2 gas sensor. The gas-tight container had aluminum windows to allow better penetration of the neutron beam, and the sample was placed behind that window. Exogenous ethylene was added in order to force senescence. A highly parallel TN beam provided high-resolution neutron images, and detailed images of the carnation ovary were obtained. VCN neutron images provided high-contrast images of water content due to the low energy of the neutron beam. From the neutron images obtained, petal wilting and dehydration, and shrinkage of the whole flower were observed. The decrease in water rate was calculated from the part of the sample in which the petal density was high. The change in the water rate corresponded with the change in respiration rate (climacteric).

Ethylene Production and Vase Life of Cut Carnation Flowers under High Temperature Conditions

Cut flowers of carnation ‘Excerea’, treated with or without silver thiosulfate (STS) showed the same vase life as when kept in Misaki, a commercial preservative, or 1 to 2% fructose with germicide at 32°C. In-rolling of petals did not occur at 32°C until day 14, even though flowers were not treated with STS. However, flowers without STS treatment showed in-rolling on day 9 at 24°C. Flowers without STS treatment, reached a climacteric peak of ethylene during day 8 to 10 at 24°C, whereas flowers at 32°C produced very little ethylene. Flowers, kept at 32°C and then transferred to 24°C, showed a climacteric peak of ethylene, but the peak was lower than that at continuous 24°C. Flowers, kept at 24°C for 1-5 days and then transferred to 32°C, produced very little ethylene. These results suggest that high-temperature keeping conditions inhibit ethylene production in cut carnation flowers.

Expression of genes for alcohol dehydrogenase and pyruvate decarboxylase in petals of cut carnation flowers in response to hypoxia and anoxia

Two full‐length cDNAs encoding alcohol dehydrogenase (ADH, EC 1.1.1.1) and pyruvate decarboxylase (PDC, EC 4.1.1.1), named Dcadh1 and Dcpdc1, respectively, were cloned from the petals of cut carnation flowers exposed to hypoxia (1.5% O2). Dcadh1 and Dcpdc1 transcripts were accumulated in large amounts in the petals of carnation flowers 2 and 3 h after the exposure of the flowers to hypoxia and anoxia, respectively. The accumulation of the transcripts was accompanied by subsequent increases in the ADH and PDC activities in the petals. The rapid and massive induction of Dcadh1 and Dcpdc1 expression and their enzymatic activities make these genes useful molecular markers for the early events of hypoxic adaptation in cut carnation flowers. The long‐term objective of this research is to induce a hypoxia‐like response in cut carnation flowers maintained under normoxic conditions in order to extend their vase life. Cut carnation flowers represent a good model system to study the molecular triggering of the hypoxic response.

Decomposition of ethylene, a flower-senescence hormone, with electrolyzed anode water.

Electrolyzed anode water (EAW) markedly extended the vase life of cut carnation flowers. Therefore, a flower-senescence hormone involving ethylene decomposition by EAW with potassium chloride as an electrolyte was investigated. Ethylene was added externally to EAW, and the reaction between ethylen and the available chlorine in EAW was examined. EAW had a low pH value (2.5), a high concentration of dissolved oxygen, and extremely high redox potential (19.2 mg/l and 1323 mV, respectively) when available chlorine was at a concentration of about 620 microns. The addition of ethylene to EAW led to ethylene decomposition, and an equimolar amount of ethylene chlorohydrine with available chlorine was produced. The ethylene chlorohydrine production was greatly affected by the pH value (pH 2.5, 5.0 and 10.0 were tested), and was faster in an acidic solution. Ethylene chlorohydrine was not produced after ethylene had been added to EAW at pH 2.6 when available chlorine was absent, but was produced after potassium hypochlorite had been added to such EAW. The effect of the pH value of EAW on the vase life of cut carnations was compatible with the decomposition rate of ethylene in EAW of the same pH value. These results suggest that the effect of EAW on the vase life of cut carnations was due to the decomposition of ethylene to ethylene chlorohydrine by chlorine from chlorine compounds.

Effect of 1-MCP (1-methylcyclopropene) on the vase life of Chrysanthemum and Carnation cut flowers

The effect of 1-MCP on extending the vase life of chrysanthemum and carnation cut flowers was studied. The flowering stems of both flowers were terminated to 50 cm. in height. Then, the flowers were pre-treated with 1-MCP at 0.3, 0.5 and 0.7g/m3 for 3 hours or 6 hours. The control flowers were placed in ambient air during the treatment. After the period of treatments the flowers were aerated then put in glass vials contained tap water. The vase life determination was conducted in a vase life evaluation room at 22 ± 1°C. Fresh weight determinations of the flowers were made just before the immersion of the flowers into the glasses of water and were repeated on the day when the vase life of the control flowers was terminated. The treatment of 1-MCP at 0.5g/m3 for 6 hours was the most effective treatment of chrysanthemum and carnation cut flowers.