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.
The effects of silver-containing compounds used for prolonging the vase life of cut rose (Rosa hybrida L. `Asami Red') flowers were investigated. Silver nitrate and RNA-Ag+tris (a ribonucleic acid-silver complex and trishydroxymethylaminomethane) increased the vase life by 2.7 days and prevented bent neck of cut rose flowers compared with the control, whereas silver thiosulfate (STS) did not have a significant effect on longevity. Fresh weights of the rose stems pretreated with silver nitrate or RNA-Ag+tris were maintained along with longer vase life. There were higher amounts of Ag+ in the basal parts of the stem in these treatments compared with STS treatment. Bacterial count at the cut surface of stems treated with either silver nitrate or RNA-Ag+tris were lower than STS-treated or control stems. These results indicated that the primary effect of silver-containing compounds on `Asami Red' roses was antimicrobial.
Aminooxyacetic acid (AOAA) at a concentration of 0.5 mM extended the vase life of carnations (Dianthus caryophyllus L. cv. White Sim) to a degree comparable to that shown by 0.1 mM aminoethoxyvinylglycine (AVG) (71 to 94%). Increases in vase life ranging from 22 to 53% were also obtained with N-[2-(2-oxo-l-imidazolidinyl) ethyl]-N’-phenylurea (EDU), carbonylcyanide m-chlorophenyl-hydrazone (CCCP), spermidine, putrescine, or spermine. Combinations of AVG and EDU or AOAA and EDU further extended the vase life 134 to 140% over that of the control flowers. These increases were additive to the beneficial effects obtained from the control preservative solution, which contained 2% sucrose and 200 ppm 8-hydroxyquinoline citrate.
Sucrose addition to the vase solution improved the postharvest qualities of cut liatris by increasing the length of inflorescences showing color and by prolonging the vase life of the spikes. The main effect of sucrose was on the development and opening of the flower heads with minimal effect on their longevity. Pulsing with concentrations of sucrose ≥10% for 20 hours prolonged the vase life of the spikes. Responses of spikes to the pulsed treatment varied greatly due to the differences in their degree of leafiness, thus limiting its commercial application. A continuous supply of 2.5% or 5% sucrose in the vase solution allowed most of the flower heads on the spikes to develop and doubled the vase life of the spikes.
Detached shoots of double-flowered peach [Prunus persica (L.) Batsch] selections Fla. 6-1 and Fla. 0-5 were successfully opened in floral solutions containing 1 to 10% sucrose in deionized water. Addition of 8-hydroxyquinoline citrate (8-HQC), gibberellic acid (GA3), or 6-benzylaminopurine (BA) to solutions did not extend vase life. Solution uptake rate decreased over the 8-day life of the shoots and was influenced by solution molarity. Xylem plugging by pectic-type materials increased with time in solution. Addition of 1% ethanol to the floral solution hastened time of first opening, decreased the extent of xylem plugging, and extended vase life. Ethanol at 2% extended vase life and increased solution uptake rate over solutions containing sucrose alone.
The vase life of cut sunflowers given a simulated transport period (3 days dry storage at 8C) was significantly enhanced by a l-hour pulse with 0.01% Triton X-100 administered before storage. The Triton pulse increased solution uptake during the l-hour pulse, decreased fresh weight loss during dry storage, and significantly improved water uptake thereafter, resulting in greater leaf turgidity and longer vase life. Leaf stomata] conductance measurements indicated that Triton X-100 maintained stomatal opening at a higher level during the pulse and after storage, but had no effect during dry storage. Chemical name used: octylphenoxypolyethoxyethanol (Triton X-100).
Immersing stems of carnation flowers (Dianthus caryophyllus L. cv. White Sim) in solutions containing a silver thiosulfate complex prepared by combining silver nitrate with sodium thiosulfate (molar ratio 1:4) doubled their vase life (from 5 to more than 10 days). The effect could be achieved by treating stems with solutions containing as little as 1.0 mM Ag with a pulse as short as 10 minutes. Silver uptake estimations indicated that a minimum of 0.5 μmol Ag was required per stem for maximum vase life and that more than 5 μmol Ag per stem was toxic.
Senescence of sweet pea (Lathyrus odoratus L.) flowers was associated with a climacteric rise in ethylene (C2H4) production. Pretreatment for 8 min with 4 mM silver thiosulfate (STS) doubled the vase life of the flowers and enhanced opening of buds on the spike. An overnight pulse at 20°C with 4% sucrose also promoted bud opening. A combined STS and sucrose treatment improved flower quality by promoting bud opening of spikes cut with tight florets, and by delaying floret senescence and abscission in both fresh and stored flowers. Aminooxyacetic acid (AOA) was less effective than STS in extending the vase life of sweet peas.
Established ground beds of leatherleaf fern were sprayed repeatedly with water, a flowable formulation of thiophanate-methyl, or one of four formulations of chlorothalonil on a predominantly weekly schedule. None of the treatments produced visible phytotoxicity symptoms or had any effect on yield (frond number and total fresh mass). However, average masses of fronds from plots treated with a liquid formulation of chlorothalonil were 21% greater than those from control plots. All chlorothalonil formulations left visible residues on the fronds and reduced frond vase life compared to fronds treated with water or thiophanate-methyl. Reduced vase life was due to more rapid desiccation of chlorothalonil-treated fronds. During those months (July—Sept.) when postharvest desiccation is most common, chlorothalonil reduced vase life of fronds by 36% to 62%. Vase life of fronds was generally reduced more by dry chlorothalonil formulations than by liquid ones, probably due to slightly higher application rates of dry formulations. Determination of the mode of action could lead to an understanding of the causes of frond curl syndrome. Until a remedy is found, chlorothalonil should not be used repeatedly on leatherleaf fern. Chemical names used: tetrachlorisophthalonitrile (chlorothalonil); dimethyl [(1,2-phenylene)-bis(iminocarbonothioyl)]bis[carbamate]) (thiophanate-methyl).
Snapdragon (Antirrhinum majus L. `Chitchat'), delphinium (Delphinium ajacis L. `Bellisimo'), chrysanthemum (Dendranthema grandiflora RAM. `Regan'), tulip (Tulipa hybrid `Golden Brush'), gerbera (Gerbera jamesonii H. Bolus `Manovale'), oriental lily (Lilium asiaticum L. `Specisiom Simplon'), rose (Rosa hybrid L. `Carnavale') and iris (Iris hollandica Tub. `Blue Magic') cut flower stems were placed at 20 °C in water containing the NO donor compound 2,2'-(hydroxynitrosohydrazino)-bisethanamine (DETA/NO) at 10 and 100 mg·L-1 and after 24 h, transferred to humidified air containing 0.1 μL·L-1 ethylene. Compared with flowers kept in water, the vase life of all eight flowers was extended by DETA/NO with an average extension of about 60% with the range being about 200% for gerbera to 10% for chrysanthemum. DETA/NO appears to have widespread applicability to cut flowers and offers a simple technology to extend vase life.