Prolonging Vase Life Research Articles

Psidium guajavaandPiper betleLeaf Extracts Prolong Vase Life of Cut Carnation (Dianthus caryophyllus) Flowers

The effect of leaf extracts of Psidium guajava and Piper betle on prolonging vase life of cut carnation flowers was studied. “Carola” and “Pallas Orange” carnation flowers, at bud stage, were pulsed 24 hours with a floral preservative. Then, flowers were placed in a vase solution containing sprite and a “germicide” (leaf extracts of P. guajava and P. betle, 8-HQC, or a copper coin). Flowers treated with 8-HQC, copper coin, and leaf extracts had longer vase life, larger flower diameter, and higher rate of water uptake compared to control (tap water). The leaf extracts of P. guajava and P. betle showed highest antibacterial and antifungal activities compared to the other treatments. Both showed similar effects on flower quality as the synthetic germicide, 8-HQC. Therefore, these extracts are likely natural germicides to prolong vase life of cut flowers.

이끼 추출물과 절화 보존제 혼용처리가 절화장미 'Enjoy'의 수명에 미치는 영향

본 연구는 이끼의 추출물을 이용하여 절화장미 'Enjoy'의 수명을 효과적으로 연장시킬 수 있는 천연 절화수명 연장제를 개발하기 위하여 수행하였다. 이끼 추출물중 R. hybrida 'Enjoy'의 절화수명 연장에 가장 효과적이었던 Hypnum jutlandicum 2 <TEX>$mg{\cdot}L^{-1}$</TEX>에 sucrose 0, 1, 3, 5%를 첨가한 후 sucrose가 R. hybrida 'Enjoy'의 수명에 미치는 영향을 분석하였다. 연구의 결과, sucrose를 H. jutlandicum 추출물과 함께 사용할 경우에는 R. hybrida 'Enjoy'의 잎이 엽록소를 상실하여 탈색되고 위조현상이 발생하며, 오히려 절화의 수명이 단축되는 것으로 나타났다. 그러나 H. jutlandicum 추출물과 HQS를 함께 사용하는 것은 R. hybrida 'Enjoy'의 수명을 증가시키는 것으로 나타났으며, 특히 HQS를 100 <TEX>$mg{\cdot}L^{-1}$</TEX> 농도로 첨가했을 때 R. hybrida 'Enjoy'의 수명연장 효과가 가장 증가하는 것으로 나타났다. H. jutlandicum 추출물 2 <TEX>$mg{\cdot}L^{-1}$</TEX> 첨가구의 pH를 조절하지 않거나(pH 3.8), pH 3.0, 4.0, 5.0로 조절하여 R. hybrida 'Enjoy'의 절화수명에 미치는 영향을 분석한 결과, pH를 조절하지 않은 pH 3.8인 보존용액을 사용하는 것이 R. hybrida 'Enjoy'의 수명이 오래감을 알 수 있었다. 이상의 연구 결과, H. jutlandicum 추출물(2 <TEX>$mg{\cdot}L^{-1}$</TEX>)에 HQS(100 <TEX>$mg{\cdot}L^{-1}$</TEX>)를 첨가한 보존용액이 R. hybrida 'Enjoy'의 절화수명을 연장시켰으며, 이끼는 주변에서 쉽게 구할 수 있어 환경오염의 피해가 없으며 천연 보존제로서 개발가치가 있을 것으로 기대된다. This study was performed to develop a natural preservative which had the most successful effect on prolonging the vase life of cut flowers Rosa hybrida 'Enjoy'. To determine the effect of sucrose on vase life of cut roses, R. hybrida 'Enjoy', 0, 1, 3 or 5% of sucrose was mixed with Hypnum jutlandicum extract. The result showed that in the case of adding sucrose to extracts from H. jutlandicum, vase life of cut flowers was shortened, along with the cut flowers losing chlorophyll, becoming decolorized and finally showing wilting phenomenon. However, using hydroxy quinoline sulfate (HQS) and extracts from H. jutlandicum together exhibited an improved effect of prolonging vase life, especially when adding 100 <TEX>$mg{\cdot}L^{-1}$</TEX> HQS, which had the effect of prolonging the vase life of R. hybrida 'Enjoy' the most. Regarding pH of extracts, 2 <TEX>$mg{\cdot}L^{-1}$</TEX> of extracts from H. jutlandicum show originally pH 3.8. This was compared with adjusted extract solutions as pH 3.0, 4.0 or 5.0. The results showed that the solution of pH 3.8 had the most successful effect on prolonging the vase life of R. hybrida 'Enjoy'. Given all the results, H. jutlandicum extract (2 <TEX>$mg{\cdot}L^{-1}$</TEX>) and HQS (100 <TEX>$mg{\cdot}L^{-1}$</TEX>) was the most effective in prolonging the vase life of cut R. hybrida 'Enjoy'. Moss is expected to be worth developing as a natural preservative since it is easy to get and causes no damage to the environment.

β-Cyclodextrin-based nanosponges as carriers for 1-MCP in extending the postharvest longevity of carnation cut flowers: an evaluation of different degrees of cross-linking

This study investigated the influence of different degrees of cross-linking of β-cyclodextrin-based nanosponges (β-CD-NSs) on the activity of the incorporated 1-methylcyclopropene (1-MCP) to extend the postharvest longevity of carnation cut flowers. The polymeric β-CD-NSs were synthesized from cyclodextrins at three varying reticulations, β-CD-NS 1:2, β-CD-NS 1:4, and β-CD-NS 1:8. These carriers were supplied to carry the nonvolatile formulations of 1-MCP at two different concentrations (0.25 and 0.5 μL L−1, ai) through stem and tissues of cut flowers of Dianthus caryophyllus L. ‘Idra di Muraglia’, both sprayed and in vase suspension. Treated cut flowers were compared to those receiving like concentrations of commercially prepared gaseous 1-MCP and to neat β-CD-NS 1:2, β-CD-NS 1:4, and β-CD-NS 1:8. Visual checks for symptoms of senescence alteration (VS), petal color variation, and endogenous ethylene production were registered daily. The β-CD-NS 1:2, β-CD-NS 1:4, and β-CD-NS 1:8 complexes favored decorative value maintenance in carnation cut flowers. In particular, the lowest suspended concentration (0.25 μL L−1) of the β-CD-NS 1:8 complex proved best for maintaining cut flower ornamental quality. β-CD-NS 1:8 treated flowers also appeared longer-lived than those treated with both doses of commercial gaseous 1-MCP. Data on petal color variation and endogenous ethylene production were strictly correlated with VS results. The potential for the formulated 1-MCP-loaded β-CD-NS suspension to induce prolonged vase life was demonstrated. Its use could yield benefits, such as a reduction in total dose and frequency of administration.

Inhibiting biofilm formation of Enterobacter sp. prevented premature withering in cut flowers

Early withering and premature flower fall are a growing menace to the cut flower industry, the reasons of which were considered to be varied from loss of water uptake, bacterial proliferation, decay in tap water etc. In the present study, we identified the bacterial biofilm formation by Enterobacter sp. and subsequent water uptake blockage as the root cause of early withering in cut flowers using Chrysanthemum, Yellow Daisy and Maroon Rose as model plants. The biofilm-forming Enterobacter sp was identified by 16 S rDNA sequencing data. Studies on biofilm were conducted by using field emission scanning electron microscope electron back scattering diffraction (FE-SEM-EBSD), Atomic force microscopy (AFM) and fluorescence microscopy. In vitro and in vivo studies were conducted with different antimicrobials to prevent biofilm formation in both conditions. Most antimicrobials were toxic to plants, but we found citric acid 1,000 μg/ml and calcium hypochlorite 50 μg/ml to be most effective in preventing biofilm formation and extending the vase life of cut flowers. We studied the synergistic action of different combinations in vivo and suggest citric acid 1,000 μg/mL, Ca hypochlorite 50 μg/mL and glucose 1,000 μg/mL as the best combination to be used for prolonging vase life of cut flowers from 10 days (non-treated) to 30 days (treated).

Effect of Pulsing Treatments for Enhancing Shelf-Life of Cut Asiatic Lilium cv. Elite

Studies were conducted on cut Asiatic Lilium cv. Elite to assess the effectiveness of various floral preservatives as pulsing treatments for delaying senescence and prolonging vase life. Uniform spikes of lilium at bud colour break stage were brought to the laboratory in the morning and placed in 8 different pulsing solutions consisting of sucrose (Suc) 5%, aluminium sulphate (AS) 400 ppm, silver thio-sulphate (STS) 2.0 mM and citric acid (CA) 1000 ppm alone and in combination with sucrose. Distilled water without any chemical served as the control. Among individual treatments, STS 2.0 mM maintained better water relations and flower quality compared to others. STS also showed superiority over other treatments when combined with Suc 5% by providing largest flower size (16.74 cm) with maximum vase life (17.29 days) owing to most-favourable water relations parameters.

EFFECT OF SOME ETHYLENE INHIBITORS ON THE KEEPING QUALITY AND EXTENDING THE VASE LIFE OF CARNATION (DIANTHUS CARYOPHYLLUS, L.) CUT FLOWERS

The aim of this research was to use the environmental safe materials compared these ones with the effect of silver thiosulfate (STS) on the keeping quality of carnation flowers. Flowers of carnation Dianthus caryophllus cv. Banyas(white flowers) were harvested at the immature stage (star stage) and were dipped in a distilled water, STS (1:4 mu) and jasmine oil at 0.015 and 0.030% for one hour. The flowers were divided in two groups. One group (0.0 time) was placed in vases with a distilled water and the second was dry stored at 0°C for 4 and 6 weeks. The obtained data indicated that the weight loss percentage increased with extending storage period. Dry storage of carnation flowers for 0.0 time and 4 weeks at 0°C showed the best results compared to 6 weeks storage. Results concerning vase life period and flower opening revealed that dipping of cut flowers in jasmine oil was the most effective treatment for enhancing flowers quality and prolonging vase life by improving water uptake, reducing depletion of sugars content and pigments in the leaves compared to the other treatments.

Seed enhancement with cytokinins: changes in growth and grain yield in salt stressed wheat plants

Leaf yellowing is a major problem in Alstroemeria and absence of leaf senescence symptoms is an important quality attribute. Two Alstroemeria cultivars ‘Yellow King’ and ‘Marina’ were sourced from a commercial farm and harvested when sepals began to reflex. Stems were re-cut under water and kept in vase solutions of gibberellin A4+7 (0, 2.5, 5.0, 7.5, 10.0, 12.5 or 15.0 mg l−1 [Provide r ]). Treatments and cultivars were combined in a factorial fashion and arranged in a completely randomised design. Application of GA4+7 in the holding solution at 2.5–10.0 mg l−1 significantly delayed the onset of leaf senescence by around 7 days and significantly increased days to 50% petal fall by ca. 2 days. Additionally, these GA4+7 concentrations resulted in higher retention of leaf nitrogen, leaf chlorophyll and also increased leaf water content, while reducing leaf dry weight, all relative to untreated controls. Cultivar ‘Yellow King’ had significantly longer vase life and a better retention of leaf quality than ‘Marina’. Our results suggest that a concentration of 10 mg l−1 GA4+7 can be used to prolong vase life, delay leaf senescence and enhance post-harvest quality of Alstroemeria cut flowers during their transport to market.

STORAGE PERFORMANCE OF GLORIOSA SUPERBA L. AS A POTENTIAL CUT FLOWER SPECIES IN EUROPE

The effect of cold storage on the vase life and quality of freshly harvested cut flower stems of Gloriosa superba L. (Glory Lily/Climbing Lily) placed in Standard Vase Solution solutions was investigated. The vase life and fresh weight of Gloriosa inflorescences were significantly affected by storage temperature. A significant difference resulted between “dry” (inflorescences stored in polythene bags) and “wet” storage in a preservative solution ‘Standard Vase Solution’ (NaHCO3 125 mg/l, CaCl2.2H2O 99 mg/l, CuSO4.5H2O 1.2 mg/l introduced by van Meeteren et al., 1999) for flower quality features during vase life period. “Wet” storage (4 oC for 7 d) of fully open Gloriosa flowers markedly improved flower keeping quality. Chlorophyll fluorescence values (F0, Fm and Fv) increased up to day 3 of vase period and then decreased over rest. Compared to other treatments, flowers kept at 4 oC (“wet” storage) for 7 days maintained a higher photosynthetic yield (0.76) during vase period. There is a significant decrease of chlorophyll fluorescence yield with increased storage temperature. The CIE L*a*b* colour system (McGuire, 1992) was used to assess the colour of petals and leaves with a Chroma meter.There is a positive influence on L* (leaf lightness) and hue angle to longer vase life and fresh weight of flowers during vase period. However, there is no significant relationship of chroma value for vase life or fresh weight. Although visual quality could be maintained for up to 10 days in cold storage at 4 oC, flower quality decreased notably after 7 days. Our results indicate that “wet” cold storage at 4 oC for 7 days has the potential to be used for delaying inflorescence senescence, prolonging vase life and postharvest quality of Gloriosa cut flowers. Gloriosa is becoming an interesting floricultural crop in Europe. There is a potential to introduce it as a cut flower and as a potted plant to the international and European market.

Longevity and quality of cut ‘Master’ carnation and ‘Red Sandra’ rose flowers as affected by red light

Cut flowering stems (45 cm long) of carnation (cv. Master) and rose (cv. Red Sandra) were placed in test tubes containing distilled water with or without commercial preservative (20 ml l−1), under fluorescent tubes of 50 ± 10 μmol m−2 s−1 Photosynthetic photon flux (PPF). A mixed radiation from fluorescent tubes with red light provided by light emitting diodes (LEDs) and monochromic red light of low 50 or high 90 ± 10 μmol m−2 s−1 was also tested in the absence of preservative solution. Both red light with high PPF and the mixed radiation under low PPF extended the vase life of cut carnations, and flower freshness could be maintained for 10.9 days compared with a water/fluorescent light control. In cut rose, the treatment containing the preservative solution under fluorescent tubes alone and in red alone, regardless of light intensity, prolonged vase life for 4.6 and 4.2 days longer than the control, respectively. Treatment with red LEDs plus high PPF resulted in complete petal opening in carnation flowers.

Effects of Exogenous Ethylene and 1-MCP on ACC Oxidase Activity, Ethylene Production and Vase Life in Cattleya Alliances

Pretreatment of cut florets of Laeliocattleya (Lc.) Irene Finney 'York' with 0.1 //I'liter'1 ethylene for 24 hr promoted ACC oxidase activity in petals and ethylene production by florets 3 days after harvest (DAH), and shortened the vase life from 7.5 to 4.0 days. The ethylene treatment did not affect ACC concentration or ACC synthase activity in the petals. Pretreatments with 1- methylcyclopropene (1-MCP) at 0.25, 0.5 and 1 fj, 1 liter"1 for 4 hr significantly prolonged the vase life of Cattleya alliances. In Brassolaeliocattleya Mem. Robert Hack 'Villa Park', ╲JJL 1 · liter'1 1-MCP application suppressed ACC oxidase activity and ethylene production until 2 DAH and doubled their vase life; ethylene production substantially increased after 4 DAH. There was no difference between single and repeated applications of 1-MCP in prolonging vase life in Lc. Sweet Meringue 'Puriavera'. A 5% sucrose vase solution prolonged the vase life of 'Villa Park' and Lc. Irene Finney 'Rachel'. A combined treatment of 1-MCP and BA had synergistic effects on the vase life of 'Villa Park'. A combined treatment of 1-MCP, sucrose and BA was most effective in prolonging vase life. These results indicate that optimum application of 1-MCP with or without sucrose and BA is feasible to prolong vase life of Cattleya alliances.

Postharvest Handling of Heliconia, Red Ginger, and Bird-of-Paradise

Heliconia (Heliconia spp.), red ginger (Alpinia purpurata), and bird-of-paradise (Strelitzia reginae) inflorescences have similar stem structures and postharvest handling regimes. Inflorescences, especially heliconia, should be harvested in the morning while still turgid, and at the most suitable stage of development which varies with the species, its proposed use, and market requirements. Treatments that extend postharvest vase life, either or both enhance water uptake or prevent water loss and provide an exogenous energy source. Use of the most suitable temperature for shipping and storage prolongs vase life. Heliconia should be shipped and stored at &gt;10 °C (50.0 °F), red ginger &gt;12 °C (53.6 °F), and bird-of-paradise at &gt;8 °C (46.4 °F). Sucrose (10% w/v), citric acid [150 mg·L-1 (ppm)] and 8-hydroxyquinoline citrate (250 mg·L-1) are major chemicals used in pulsing and holding solution for bird-of-paradise. Holding solutions for red ginger are similar except 2% (w/v) sucrose is recommended. The response of heliconia inflorescences to different pulsing and holding solutions has been shown to be negligible. A 200-mg·L-1 benzyladenine spray extends the vase life of red ginger and heliconia. Hot water treatment of red ginger at 49 °C (120.2 °F) and 50 °C (122.0 °F) for 12 to 15 min extends postharvest vase life, kills most of the pests that infest red ginger, and reduces the geotropic response. The major postharvest problems are saprophytic mold on bird-of-paradise, negative geotropic response of red ginger, and insect infestation of all three flowers. There is no reported method to control the postharvest nectar and slime production on bird-of-paradise that provides a substrate for saprophytic mold growth. Dipping inflorescences in benomyl or thiobendazole (TBZ) at 200 mg·L-1 does help control postharvest mold growth in bird-of-paradise and heliconia. Compared to most temperate flowers, there is a need for greater understanding of morphological and physiological factors that limit the vase life of heliconia, red ginger and bird-of-paradise flowers.

Trehalose plus Chloramphenicol Prolong the Vase Life of Tulip Flowers

The tepals of cut tulips (Tulipa gesneriana L. cv. Ile de France) kept at 20 °C had severely wilted 7 days after flower opening. Suppression of abscission and undesirable growth of tepals is required to extend vase life. Treatment with 50 mm trehalose in combination with 50 μm chloramphenicol (CAP) delayed abscission by 4 days compared with stems placed in distilled water or CAP without trehalose. Only 4% of trehalose+CAP-treated flowers exhibited tepal abscission 7 days after harvest, while 82% and 60% of flowers held in distilled water and CAP, respectively, did so; the tepals of trehalose+CAP-treated flower stems contained 50% more water than did those treated with CAP alone. Further, trehalose did not promote elongation of epidermal parenchyma cells in tepal tissues, but maintained radial enlargement of the cells. Thus, trehalose+CAP treatment is effective in prolonging vase life without abscission, water loss, or elongation of cells in tulip tepals, but slight wilting occurs in leaves.

Methanol, ethanol and other compounds retard leaf senescence and improve the vase life and quality of cut chrysanthemum flowers

The effect of methanol, ethanol, benzyladenine (BA) and paclobutrazol on retarding senescence of the leaves of cut chrysanthemum flowers and thus prolonging their vase life, was studied. All substances tested extended the vase life, limited fresh weight loss and increased chlorophyll content. Methanol applied continuously and BA as a pulse increased quantum yield of photosynthesis in the leaves. In addition, BA, and methanol to a lesser extent, prevented the formation of anthocyanins in the petals, allowing the flowers to retain their natural white color and to prolong vase life even longer. All substances, methanol in particular, caused a decrease in the Chl a:Chl b ratio, indicating a better adaptation of the photosynthetic apparatus to low light regimes, and potential capacity of these substances to facilitate acclimatization of cut flowers to interior environments. In terms of overall performance, BA as a pulse, followed by methanol, were the most effective treatments.

シュッコンカスミソウ切り花の品質保持に及ぼす輸送環境の影響

小花が30%開花した段階で採花したシュッコンカスミソウ'ブリストル・フェアリー'の切り花に対して, 0.2mM silver thiosulfate (STS)と4%ショ糖を含む溶液で3時間の前処理を行ったところ, 小花の開花が促され, 品質保持期間が延長された.切り花の品質保持に対する低温輸送の効果は前処理の有無に関係なく認められたが, 予冷の効果は前処理を行った切り花でのみ認められた.輸送中に切り花が高温あるいは急激な温度の上昇にさらされると, 段ボール箱内でエチレンや二酸化炭素の蓄積が促され, このことがおそらく高温輸送下での黒花発生の一因であると考えられた.加えて, 25℃24時間の乾式輸送は, 切り花に著しい水ストレスを生じさせ, 輸送後の再吸水を不良にした.

Effect of hot water on red ginger (Alpinia purpurata) inflorescence vase life

Abstract Different ranges of temperatures and exposure times were studied to determine suitable hot water treatments to extend red ginger vase life. Hot water at 50°C for 12–15 min showed a high potential to prolong vase life. The threshold for damage on the flower bracts was represented by the equation temperature =55.23−4.5 log ( exposure time, min ) , R 2 =0.97 ( P =0.0001), with ≤5% of total bracts damage. Damage caused by hot water treatments correlated with the amount of rainfall 7 days before harvest ( P =0.004), whereas vase life of hot water-treated flowers showed a negative correlation with the amount of rainfall 1 month before harvest ( P =0.04). Preconditioning flowers at 40°C for 15 min before hot water (50°C, 12 min) significantly reduced damage from the hot water treatment. Preconditioned flowers lost their tolerance to the hot water treatment if the intervening period between preconditioning and hot water treatment, was longer than 6 h. The suggested treatment to extend vase life was a preconditioning at 40°C for 15 min, standing in the bucket of water at room temperature (22±2°C) for 1 h, and then a hot water treating at 50°C for 12–15 min.

Growth, Flowering, and Postharvest Performance of Single-stemmed Rose (Rosa hybrida L.) Plants in Response to Light Quantum Integral and Plant Population Density

The cut rose, grown as a single-stemmed crop, resembles a potted plant and can be adapted to transportable bench systems. Potentially, this cultivation method could increase control of rose development, flexibility of production and produce, and automation of difficult or laborious cultural operations. Synchronous growth and flowering is considered important. The effects of increased quantum irradiation integral and plant density on shoot growth, fresh biomass production, and bloom quality were studied as single-stemmed rose plants (Rosa hybrida L.) `Kordapa' Lambada, `Tanettahn' Manhattan Blue, `Tanorelav' Red Velvet, and `Sweet Promise' Sonia grown under 20 hours photoperiods at 23 °C average air temperature. Plants were grown in rockwool cubes on ebb and flood benches irrigated with a complete nutrient solution, and were supplied with carbon dioxide at 1000 μmol·mol-1. Increased the daily quantum integral from 17.8 to 21.0 mol·m-2·d-1 increased fresh biomass efficiency, stem diameter, and specific fresh mass while number of nodes, number of five-leaflet-leaves, plastochron value, and stem length at anthesis decreased. Fresh mass at anthesis was not affected by the treatments. Increasing plant population density from 100 to 178 plants/m2 increased stem length at visible flower bud, and reduced both fresh biomass efficiency and specific fresh mass. These effects are suggested to be related to assimilate supply and translocation, and light perception of the roses. High quantum integral slightly reduced flower diameter but in general, quantum integral or plant density did not affect bloom quality or vase life. Use of preservative floral solution generally improved rose flower diameter and vase life. In Lambada increased light quantum integral prolonged vase life, but use of preservative solution did not. The cultivars Sonia and Red Velvet required 19 to 20 days from cutting/planting until onset of bud growth, 29 to 34 days until visible flower bud, and 39 to 49 days until anthesis. Red Velvet roses were ≈60 cm long at anthesis, and had larger stem diameter and growth rate, accumulated more fresh biomass, were most efficient producing fresh biomass, and had higher specific fresh mass among the cultivars. Light quantum integral is suggested to be used as a means to synchronize single-stemmed rose plant development.

Improving the Longevity of Cut Roses by Cool and Wet Transport.

Cut 'Bridal Pink' roses, pre-cooled for 2 hr, were subjected to simulated transport for 0, 24, 48 and 72 hr at 20°C or 5°C ; their vase life was then evaluated by placing them in deionized (DI) water at 20°C under a 12-hr photoperiod. The vase life of control (no transport) cut flowers was rated to be 9.2 days. When cut flowers were transported dry in carton boxes for more than 24 hr at 20°C and for more than 48 hr at 5°C, they displayed bent necks during the transport and some buds failed to open, shortening their vase life. Contrarily, when flowers were transported wet with their stem bases in DI water, they maintained their fresh weight, especially at 5°C, thus prolonging vase life, although flower buds opened during the transport at 20°C. Substituting 0.3 mM 8-hydroxyquinoline sulfate and 0.1 M fructose for DI water during the 72-hr transport period at 5°C, the vase life of cut roses was extended more than 2 times that of dry transported ones. A flexible vial (a water-proof plastic wrapper containing hydro-wool and a tie, Flower Mate, CI Kasei Co. Ltd., Tokyo) was used to pack cut flowers wet in carton boxes as substitutes for buckets.

Postharvest Dip in a Natural Lipid, Lysophosphatidylethanolamine, May Prolong Vase Life of Snapdragon Flowers

We investigated the use of lysophosphatidylethanolamine (LPE) for prolonging vase life of snapdragon (Antirrhinum majus L.). Freshly cut snapdragon spikes were set into a LPE solution at 25 mg·L-1 for 24 h and then transferred to deionized water. The vase life was enhanced by LPE. The flowers on spikes treated with LPE showed symptoms of wilting or browning 4 or 6 days later than those on the spikes given deionized water in inbred or `Potomac White', respectively. All the spikes were of marketable quality for 5 to 7 days after harvest when treated with LPE, whereas in the control only about half of the flowers were of marketable quality at 2 days after harvest. LPE treatment also delayed fresh mass loss, lowered endogenous ethylene production, and reduced ion leakage. These results suggest that LPE has commercial potential in enhancing vase life of snapdragons.

Effects of Silver Thiosulfate, Sucrose, and Calcium Nitrate on Vaselife of Ebenus cretica L.

Ebenus cretica, Leguminosae, an endemic perennial bush of Crete, is being studied as a potential new cut flower crop. Forty-centimeter-long spikes with two to three inflorescences and six to eight compound leaves were harvested from 5-year-old plants grown from seed at the farm of the TEI, when 1/3 of the florets had opened, and were treated with various preservatives. Flower quality was evaluated morphologically combined with measurements of chlorophyll content in leaves and anthocyanin in petals. Without any postharvest treatments, inflorescences held in a solution of 100 ppm 8-hydroxyquinone sulfate (HQS) in DI water had an average vaselife of 6.8 days. Pulsing with 0.6 mM silver thiosulfate (STS) for 2 h extended vaselife up to 8.4 days. However, when ethephon was added in the solution, vaselife was significantly reduced, causing leaf yellowing and flower senescence, which suggests sensitivity to exogenous ethylene. A solution of 0.2% Ca(NO3)2 prolonged vaselife by 2.7 days, whereas higher concentrations resulted in flower discoloration and decreased flower quality. Sucrose solutions of 0.5%, 1%, 2%, and 4% had no positive effect on flower longevity. Furthermore, the higher concentrations caused leaf yellowing and petal discoloration decreasing vaselife and quality of flowers compared to control. Samples of inflorescences were taken every second day for chlorophyll (a and b) and anthocyanin measurements. The concentrations recorded were highest in the 0.2% Ca(NO3)2 treatment and were significantly correlated to flower longevity. Results indicate that Ebenus cretica may be used as a cut flower crop; however, due to the genetic variability of the Ebenus plants, a breeding line should be developed before the crop reaches the floricultural market.

Prolonging the Vase Life of Snapdragons and Carnations with a Natural Lipid, Lysophosphatidylethanolamine (LPE)

Freshly cut snapdragon (Antirrhinum majus L) spikes or carnation (Dianthus caryophyllus L cv. White Sim) stems were put in LPE (10 ppm for carnation, 25 ppm for snapdragon) solution for 24 hours and then transferred to deionized water. Parallel controls were kept continuously in deionized water. Snapdragon spikes were harvested when they had one-third of the florets opened which is a standard commercial practice. The carnations used in the experiment were harvested at three different stages of flower development starting from open brush bud stage (Stage IV) to fully opened (Stage VII, petals 45(to the stem) flower. LPE treatment delayed senescence in snapdragon by four days. Furthermore, it enhanced the opening of floral buds and opened all the florets on every spike. LPE treatment also significantly delayed loss in fresh weight of spikes associated with senescence, lowered the endogenous ethylene production and reduced ion leakage from florets. LPE had a similar effect on fresh weight and ion leakage from carnations if it was applied at an early stage of flower opening. Older carnations (Stage VII) were found unresponsive to LPE. In conclusion, LPE has the potential in enhancing the vase life of snapdragons and carnations. Carnations must be harvested at the open brush bud stage for effective LPE application. Our results suggest that LPE is prolonging vase life of cut flowers by reducing ethylene production and maintaining membrane integrity.