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Iris hollandica `Blue Magic' was treated with deionazed water as a control, 3% sucrose (Suc), 3% sucrose plus 0.4 mm silver thiosulphate (Suc+STS), 3% sucrose plus 200 mg·L^-1 8-hydroxyquinoline sulphate (Suc+HQS) and 3% sucrose plus 100 mg·L^-1 benzyl amino-purine (Suc+BA) for 4hrs and then transferred to tap water. The vase life treated with Suc+BA was extended 4 days longer than that of control. The treatment Suc+STS or Suc+HQS did not improve vase life. The amounts of water uptake and transpiration by all treatments decreased after harvest, but those values were higher in cut iris treated with Suc+BA than in those with control. Cut flowers treated with by Suc+BA markedly improved water balance, comparing with control which was quickly changed to minus value. Anthocyanin content in petals of cut flower treated with Suc+BA was 3.5 fold higher than that of control. The treatment by Suc+BA delayed discoloration in petals and senescence of cut Iris. Peroxidase (POD) activities of all treatments were reached maximum at 4th day after treatment and decreased thereafter. POD activity was highest when the cut iris was treated with Suc+BA. These results show that the use of Suc+BA is most effective treatment for improving the vase life and quality of cut Iris flowers.

Two cultivars of tulip (Tulipa gesneriana L.) were used to check the effect of trehalose-feeding on longevity of vase life. `Oxford' plants were grown from bulbs, and trehalose-fed cut flowers were compared with the intact plants grown in pots. `Pink Diamond' flowers were obtained commercially as cut flowers from the market, and trehalose-feeding was examined by using only flower parts. In both cultivars of plants, it was confirmed that trehalose-feeding enhanced longevity of the vase life significantly at room temperature. Additionally, mechanisms of prolonging the vase life with trehalose-fed flowers were studied by comparing the water status in the zone of elongation of tulip tepals when their growth rates were modified with different treatments. In the elongating region of tulip tepals, cell elongation rates were linearly correlated to sizes of the growth-induced water potential regardless of treatments. It was found that trehalose-feeding reduced the hydraulic conductance, resulting in a decrease in cell elongation rates. Also, trehalose helped to maintain turgor of tepal cells for longer periods. Furthermore, trehalose enhanced pigmentation in tepals, and thus, trehalose is believed to have had a role in altering the metabolism in elongating cells and in reducing hydraulic conductivity in membranes.

Placing a daffodil (Narcissus pseudonarcissus L. `Carlton') flower in a vase with a rose (Rosa hybrida L. Sonia) flower reduced water uptake by the rose and resulted in precocious wilting of its leaves and flower and in pedicel bending. These symptoms were also observed when mucilage from daffodil stems was placed in the vase water. The effects of the mucilage and the daffodil stem were overcome by adding 8-hydroxyquinoline (HQC) to the vase solution. HQC inhibits ethylene production and is an antimicrobial compound. Aminoethyoxyvinylglycine (AVG) or silver thiosulfate (STS), inhibitors of ethylene synthesis and action, respectively, did not alleviate the mucilage effects, but sodium hypochlorite, an antimicrobial compound, did. Bacterial counts in the basal 5-cm segment of rose stems increased after placing mucilage or a daffodil stem in the vase water, and counts were reduced by adding HQC or sodium hypochlorite. One daffodil stem also reduced the vase life of tulips (Tulipa gesneriana L. `Frappant' and `Apeldoorn'), which showed precocious leaf yellowing. This was not alleviated by HQC and was also found when mucilage was placed on the leaf surface. Placing mucilage on the leaf produced no effect in roses. Separating the mucilage indicated that the effect in roses is mainly due to the sugar and polysaccharide fraction and the effect in tulips is due to a fraction containing several alkaloids. The results indicate that the decreased vase life of rose flowers, after one daffodil is placed in their vase water, is due to daffodil mucilage, which, in the rose cultivar tested, blocks water uptake, mainly as a result of increased bacterial growth. In the tulip cultivars tested, the negative effect on vase life is primarily due to mucilage toxicity.

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.

Cut snapdragons (Antirrhinum majus L. cvs. Fujinoyuki, Oakland, and Bismarck) were harvested at three different stages and pulsed with silver thiosulfate (STS). Then, the flowers were treated with several preservative solutions to test the effects on vase life and flower quality. Proper storage methods were also investigated. The best harvesting time of snapdragon was when seven to nine florets were opened in a spike. The flowers harvested at this stage had more fresh weight, increased number of opened flowers per spike, and longer vase life than those harvested at earlier stages. Pulsing with 0.2 mM STS for 16 h improved flower quality and prolonged vase life. The preservative solution containing 2% sucrose + 150 ppm 8-hydroxyquinone citrate (HQC) + 25 ppm AgNO₃ prolonged vase life. However, this solution caused longer internode between florets and excessive elongation of spike. The preservative solution containing 2% sucrose + 150 ppm HQC + 25 ppm AgNO₃ + 50 ppm daminozide improved flower quality by prolonging vase life, reducing the length of internode between florets, and preventing excessive elongation of spike. The flowers held in 50% 7-Up had 2 times prolonged vase life compared to water control. The flowers held in 4% ethyl alcohol also had prolonged vase life and increased fresh weight. Ethylene caused floret abscission and STS pretreatment prevented this floret abscission. Ethylene production in cut snapdragons maintained 2 to 6 nl/g fresh weight per h during vase life. The prolonging storage at low temperature (1C) shortened vase life. The flowers pretreated with STS, and then held in preservative solution during cold storage, had better flower quality and longer vase life than those in plain water.

Rosa ×hybrida `Samantha' plants were grown under high-pressure sodium (HPS) lamps, HPS lamps fitted with blue gel filters to reduce the red to far-red (R:FR) ratio, or metal halide lamps. R: FR ratios were 1:0.95, 1:2, and 1:0.26 for HPS; filtered HPS, and metal halide, respectively. Although the R: FR ratio for metal halide was 3.5 times higher than for HPS, the total energy from 630 to 750 nm was 2.8 times lower. At a nighttime supplemental photosynthetic photon flux of 70 to 75 μmol·m^-2.s^-1, plants under HPS and metal halide lamps produced 49 % and 64% more flowering shoots, respectively, than those under filtered HPS (averaged over two crop cycles). The quality index for flowers under HPS, metal halide, and filtered HPS was 25.0, 23.3, and 18.5, respectively. Vase life was 10 to 11 days, regardless of treatment.

Experiments were conducted to determine the effect of dipping open `Scania' carnation flowers in aqueous solutions of benzyl adenine (BA) (0, 13, 26, 39, and 52 mg·L^-1) and gibberellic acid (GA₃) (0, 10, 20, 50, and 100 mg·L^-1) on flower vase life. Flowers were dipped for two minutes in BA or GA₃ solutions, and visual symptoms of flower senescence were periodically recorded based on distortion, discoloration, and permanent wilting of the petals. In general, visual symptoms of senescence progressed more slowly in BA-treated flowers than in GA₃ - treated and control flowers. One week after treatment, the only flowers with satisfactory appearance (slight or no petal distortion, wilting or discoloration) were those treated with BA at the rate of 13 mg·L^-1 and GA₃ at the rate of 50 mg·L^-1.

Three sources of water—WAPA, potable water produced by the Virgin Islands Water and Power Authority, cistern or rain water collected in below-house concrete tanks and bottled water were evaluated with and without addition of Flora Life (FL) preservative under greenhouse conditions for keeping cut Anthurium blooms. Significant differences in water source effects were recorded with untreated WAPA water having the longest vase life (VL) (29 days) followed by cistern and bottled water (23 days). Collectively, blooms in untreated water had a VL life of 24 days in contrast to 21 for FL-treated water. Untreated cistern and bottled water produced similar VL days, but the addition of FL significantly lowered the VL of cut flowers in bottled water. The apparent suitability of WAPA water for preserving cut Anthurium is significant since it is the least desirable for drinking and cooking in the VI and is less expensive than bottled water, but more so than cistern water.

Abstract

Immersing the cut stem of flowers for 24-72 hours in a solution containing thiabendazole and sucrose facilitated opening, improved quality, and prolonged vase life of bud cut carnations, mini-carnations and chrysanthemum harvested at the bud stage, and of gladiolus, mini-gladiolus, snapdragons and gypsophila harvested considerably earlier than recommended commercially. This treatment was shown to be more effective than 8-hydroxy-quinoline, in all cases, and more effective than silver nitrate treatment in the case of gypsophila. The flowers treated with thiabendazole were larger and heavier, and retained their decorative value for a longer time. Adding 8-hydroxyquinoline to thiabendazole solutions to form the “TOG” formula improved the effectiveness of the treatment for commercial use and allowed re-usage of the solution several times.

Abstract

Short pretreatments of stems of anthurium flowers (Anthurium andraeanum André) with silver nitrate solutions increased vase life by 40 to 60% after a simulated shipping. Significant improvement was obtained with a single 10-minute treatment with 1 mm silver nitrate. Maximum postharvest life was obtained with flowers treated with silver nitrate within 12 hours of harvest. Silver nitrate treatment was effective on flowers ranging from half to full maturity. No measurable silver was translocated to the spathe or spadix. Silver thiosulfate complex was not as effective as silver nitrate. For response to silver treatment following simulated shipping of 3 days, 2 cm of stem had to be removed before placing in a vase solution. Continuous maintenance of the flower before and after simulated shipping in a commercial preservative was not significantly better than a single pulse with silver nitrate or a combination of silver nitrate pulse and commercial preservative.