Função das soluções preservativas nos mecanismos fisiológicos para atrasar o amarelecimento das folhas em hastes florais de Alstroemeria

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.

Tulip (Tulipa gesneriana L.) is an important and highly valuable flower of the cut flower industry. The most critical step in its cultivation is to break dormancy in order to initiate the growth, especially in tropical and sub-tropical areas of the world. Therefore, the current research was conducted to break bulb dormancy and foster the growth of tulip in Potohar region with the help of different primers. The objective of this study was the selection of best primer at appropriate concentration level to enhance growth, yield and vase life of the flower. Tulip bulbs were treated with different primers: T0 (distilled water), T1 (chitosan @ 5 g/L), T2 (gibberellic acid @ 0.15 g/L), T3 (humic acid 160 g/L), T4 (imidacloprid 19 g/L) and T5 (salicylic acid 0.1 g/L) for 24 hours, respectively. The experiment was laid out using Complete Randomized Design (CRD) with three replications. Statistical results revealed that characteristics including early germination, plant height, number of leaves, stalk length, fresh and dry weight of flower, weight of bulbs, diameter of bulbs and number of daughter bulbs were significantly increased in T2. Whereas, leaf area, diameter of stem and flower was maximum in T0. Plants under T3 showed an increase in chlorophyll content of leaves. While floral characteristics like early formation and opening of flower bud, more number of flowers and vase life were improved in T1. Thus, statistical results showed that priming can effectively help to improve morpho-physiological attributes of tulip.

In this study the effects of different treatments were investigated for the purpose of storage of cut narcissi for improving marketing opportunities. Flowers of a wild population of single flowered Narcissus tazetta L. from Izmir/Seferihisar which of the flowers are collected and sold in that region and a double flowered cultivar of N. tazetta L. cv Karaburun Nergisi were used. Two experiments were carried on. Experiment I: After harvest as hydration experiment flowers were hydrated for 7 hours: in in tap water (U1) (Control), in silver thiosulfate (S.T.S) (22.5 ppm) solution (U2) or in S.T.S (22.5 ppm)+ 8-hydroxyquinoline citrate (8-HQC) (150 ppm) + sucrose (%5) solution and their vase and mean floret life were compared. Experiment II: The flowers applied with U1, U2, and U3 treatments during hydration were taken up in tap water and as fourth treatment flowers those applied same solution with U3, wrapped in newsprint and then polyethylene without water (U4). And vase and mean floret life of flowers of these four treatments (U1, U2, U3 and U4) were determined after different storage durations. Four different storage durations (2, 4, 6, and 8 week) at 0 ± 1 °C were investigated. The effects of treatments on vase and floret life were examined. Solutions those were used for hydration increased the vase life of both culture and wild narcissi with respect to control before storage. Positive effects of these treatments were also determined at different storage durations. Culture narcissus showed the highest vase life with U4 treatment which was followed by U3, U2 and with the lowest value U1 (control). The results of three treatments (U2, U3, and U4) were placed in the same statistical group for the flowers of wild narcissus which were higher than control (U1). It was determined that the longer the storage time was shortened the vase life but even after a long storage period of eight week, satisfactory vase life values (4,6 – 5,1 day) were obtained from both wild and culture narcissi

Introduction: Carnation (Dianthus caryphyllus L.), from Caryophyllaceae family, is one of the most important cut flowers in the world that its short vase life reduces the economic value. Postharvest longevity of cut flowers can be prolonged using carbohydrates (sugars) in a vase jar. Cut flowers undergo some physiological and biochemical changes that often lead to an early senescence. To delay the aging process in cut flowers, it is necessary to evaluate many aspects of preparation for storage conditions, especially preservative solutions that affect the quality and longevity of these flowers. Many flowers are harvested before they are fully developed, to ensure a long postharvest life and to minimize mechanical damages that might occur during handling. The growth and development of flower buds on cut flowers require food (especially carbohydrates), which is stored in the leaves and stems. These stored carbohydrates can be mobilized for the flower bud to use but maybe they are insufficient when the buds are harvested at a tight-bud stage. To maintain metabolic activities, including respiration, even for cut flowers that have reached full development, it is necessary to provide adequate reserves to achieve acceptable postharvest life. When stored materials are low, leaves and flowers age faster and the petals fade. Under these conditions, supplements can be provided to the flowers by adding sugars such as glucose, fructose and sucrose to the vase solutions. However, it is important to note that a sugar solution is also suitable for the growth of microorganisms, so that an antimicrobial agent should be added to the vase solution as well. Many researches were carried out on prolonging the vase life of cut carnation flowers with different preservative solutions together with an antimicrobial agent. Studies on postharvest longevity of cut carnation flowers using sugars as preservative solutions is low. Therefore, the aim of the present study was to evaluate the effect of sugars (glucose, fructose and sucrose) and application time on vase life and some physiological parameters of carnation cv. “Yellow Candy” cut flowers.Materials and Methods: A factorial experiment based on completely randomized design in three replicates was performed in order to investigate the effect of different levels (0, 50 and 100 g/L) of three types of sugars (glucose, fructose, and sucrose) and two sugar application times (the first and second 24 h) on vase life of carnation cv. Yellow Candy cut flowers. Some other traits such as water uptake, dry mater, relative fresh weight, protein and carotenoid of petal, leaf chlorophyll, POD and SOD enzymes activity and MDA were also measured. The statistical analysis of data was performed using Statistical Package for Social Sciences (SPSS) v 16.0. Least significant difference (LSD) test at P < 0.05 was used to find out the significance of differences among the mean values.Results and Discussion: Results showed that the effect of different levels of sugars on all evaluated traits was significant. Each three levels of sugars at each two applied times caused to increase vase life and relative traits. Maximum vase life (18 days) was obtained in 50 g/L glucose at the first 24 h with no statistically significant differences with the 100 g/L sucrose and fructose at the first 24 h. The highest water uptakes and dry matter, the lowest POD and SOD activity and minimum MDA were obtained in treatment of 50 g/L glucose at the first 24 h. The highest petal protein content, chlorophyll a, b, and total chlorophyll were achieved in treatment of 50 g/L glucose at the second 24 h. The use of sugars at the first 24 h was more effective in improving the vase life than at the second one. Therefore, application of glucose, preferably in the early hours of harvesting flowers, can be recommended as a prolonged postharvest carnation Yellow Candy cut flowers. Positive effect of external holding solutions in vase jar particularly sugars together with an antimicrobial agent on prolonging the vase life of many cut flowers have been shown. Treatment of some cut flowers with sucrose increased glucose and fructose in petals. External sugars can be provided to cut flowers by dissolving a known amount of sugar, along with an antimicrobial agent, into the vase solution. The optimum concentration of sugar varies significantly depending on the flowers being treated. Concentration of 2% sugar is used to keep most flowers in the vase solution. However, some other flowers require higher concentrations, such as 4 to 6%. Some flowers are damaged when treated with concentrations higher than 1%. Therefore, it is important to examine each flower before treating it to determine the optimal concentration of sugars. Sugars are a source of energy and carbon for cut flowers and play an important role in decreasing the protein degradation and ethylene production, maintenance of osmotic balance, increasing water uptake, and finally delaying in senescence process.

Ethylene action and synthesis inhibitors were evaluated for their effects on cut peony flower longevity and quality. Field-grown 'Karl Rosenfield' and 'Sarah Bernhardt' cut peony flowers were treated for two hours with either 0.5 mM silver thiosulfate (STS) or 0.60 μl L -1 1-methycyclopropene (1-MCP) ethylene action inhibitors, Floralife ® (FLO) at the label recommended dosage, 0.60 μl L -1 ethylene (Eth), or deionized water (CON) before being stored for nine weeks. In addition, cut peony flowers temporarily held for three weeks in refrigerated storage were treated for two hours with either 100 μl L -1 aminoethoxyvinylglycine (AVG), an ethylene synthesis inhibitor or deionized water and monitored for an additional seven week storage period. Vase life, flower weight, bud diameter, degree of petal openness, petal color, rate of ethylene and carbon dioxide (CO 2 ) evolution, and percent disease incidence were monitored. 'Karl Rosenfield' flowers were unaffected by all treatments over the storage time. 'Sarah Bernhardt' flowers responded to STS and 1-MCP treatments during CO 2 evolution, petal color and percent disease incidence measurements. Flowers treated with AVG had slowed reproductive organ development and increased disease incidence. The Floralife ® treatment promoted the longest flower vase life; 1-MCP-treated flowers had the shortest vase life. Flowers treated with STS were lighter and less vivid in color, whereas FLO-treated flowers had darker and more vivid petal color. AVG had little to no effect on flower quality or vase life, with the exception of delayed flower development and increased disease incidence. The decline of vase life and flower quality was significantly related to the length of storage time. The ethylene antagonists used in this study were ineffective at increasing storage longevity and quality of cut peony flowers.

The effects of postharvest pretreatments on vase life, keeping quality and carbohydrate concentrations in cut sweet pea (Lathyrus odoratus L.) flowers were investigated. Compared to the control, all treatments promoted floret quality and extended longevity. The cut flowers held in the solution containing sucrose + 8-hydroxyquinoline (Suc+HQS) was more effective in promoting absorption rate, achieved greater maximum fresh mass, had better water balance for a longer period, extended the vase life (up to 17 d), and delayed degradation of chlorophylls. The same treatment also enhanced the concentration of soluble carbohydrates in the petals and stems and leaf chlorophyll (Chl) content, whereas it was lowest in silver thiosulphate (STS) treatment. However, concentrations of anthocyanin in the petals were higher for treatment with sucrose or STS plus sucrose than in control or STS alone treatments. Our results suggest that pulse treatment with HQS plus sucrose for 12 h is the most effective for improving pigmentation and use as a commercial cut flower preservative solution to delay flower senescence, enhance quality, and prolong the vase life of sweet pea. The results also showed that soluble carbohydrate concentration in petals and stems is an important factor in determining the vase life of sweet pea flowers.

A pulse treatment of sucrose at 0, 20, 40, 60, 80, 100, and 120gL(superscript (-1)) in combination with 8-hydrox-yquinoline sulfate (HQS) at 200 mg L(superscript (-1)) for 10h was evaluated daily for its effect on the vase life and flower quality of cut rose flowers. The pulse treatment of sucrose at above 80gL(superscript (-1)) produced a vase life of 6 to 7 days, while at below 80gL(superscript (-1)) vase life was maintained for 4 days on average. The pulse treatment of silver thiosulfate (STS) at 0.2mM for 2h or STS for 2h followed by sucrose at 120gL(superscript (-1)) supplemented with HQS for 10h extended the vase life of cut rose flowers to about 9 and 10 days, individually. On the other hand, a pulse treatment with sucrose or distilled water in combination with HQS maintained vase life for 7 and 3 days, respectively. Flower quality of specimens treated with STS followed by sucrose in combination with HQS was better than that of those treated with STS alone. Although visual quality could be maintained for up to 13 days in STS followed by sucrose in combination with HQS, flower quality decreased notably after 10 days. The ethylene production was greatest in untreated rose flowers (about 3h after harvest) and decreased after chemical solutions treatment. The inhibition of ethylene production was greater in sucrose in combination with HQS than with STS or STS followed by sucrose along with HQS, although the effectiveness of the latter for maintaining rose vase life was better than the former.

Alleviation of effects of exogenous ethylene on cut ‘Master’ carnation flowers with nano-silver and silver thiosulfate

Research was conducted to further modify the forcing solution system in order to expedite the propagation of woody plants, such as Spiraea canescens, Lonicera maakii, and Cornus alba. Time of immersion in solutions containing 5 mM silver thiosulfate (STS) was compared with the basic forcing solution reported by Yang and Read (1989), a solution containing 200 mg 8-hydroxyquinoline citrate per liter and 2% sucrose. Other treatments employed were gibberellic acid (GA3) 50 mg per liter for 24 h and a combination of STS and GA3 for the same amount of time. Increasing the time in STS solution up to 24 h led to higher percent budbreak and shorter time to budbreak for all the three species examined. The combination of STS and GA3 was the most effective treatment overall in reducing time of budbreak and increasing percent of budbreak. All STS treatments studied showed similar responses in shoot elongation. However, treatments with GA3 alone, and in combination with STS showed more than a doubling in shoot length compared to all STS treatments studied and the control. Implications based on SEM observations will be presented.

An experiment was conducted to study the effect of different concentrations of silver thiosulphate (STS) on flower longevity of Clarkia pulchella Pursh. The buds were subjected to 0.1, 0.25, 0.5, 0.75 and 1 mM of STS for 1 h pulse treatment. A separate set of flowers kept in distilled water was designated the control group. STS treatment resulted in improved flower longevity besides maintaining higher fresh and dry mass, water content and floral diameter. Conversely, total phenols, lipid peroxidation and lipoxygenase (LOX) activity decreased. The flowers treated with STS showed a significant increase in the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Amongst various grades used, 0.5 mM STS was found to be most effective in enhancing the flower longevity by 1.5 days. The present study reveals that STS maintains lower LOX activity, thereby increased membrane stability index by improving the activity of antioxidant enzymes.

Cassava, which produces edible starchy roots, is an important staple food for hundreds of millions of people in the tropics. Breeding of cassava is hampered by its poor flower production, flower abortion, and lack of reproductive prolificacy. The current work determined that ethylene signalling affects floral development in cassava and that the anti-ethylene plant growth regulator silver thiosulfate (STS) mitigates the effects of ethylene on flower development. STS did not affect the timing of flower initiation, but improved early inflorescence and flower development as well as flower longevity such that flower numbers were increased. STS did not affect shoot and storage root growth. Studies of silver accumulation and treatment localization support the hypothesis that the beneficial effects of STS are confined to tissues of the shoot apex. The most effective timing of application was before inflorescence appearance extending to post-flower appearance. Based on this work a recommended protocol for STS use was developed. This work has the potential to improve methods for enhancing cassava flower development in breeding nurseries and thereby synchronize flowering of desired parents and enable the production of abundant progeny of desired crosses.

In order to improve the post production quality of cut flowers of Rosa hybrida L. cv. Baroness, the effect of 8-hydroxyquinoline sulfate (8-HQS), silver thiosulfate (STS) and 1-methylcyclopropene ( I-MCP) were investigated. 8-HQS was used at 200 and 400 ppm with or without sucrose at 50 g LI. STS was used at 0.2, and 0.4 mM with or without sucrose at 50 g 1-I. l-MCP was used at 0.3, 0.5 and 0.7 g in-3 for 6h.&#x0D; The postproduction quality was improved as a result of using any chemical treatment comparing with untreated control. All the treatments of 8-HQS increased the vase life and minimized the percentage of weight loss of rose cut flowers compared to the control. The vase life was lorger when 8-HQS was combined with sucrose. The best treatment of 8-HQS was 400 ppm 8-HQS + 50 g 1-1 sucrose. STS treatment led to prolong the vase life and minimized the percentage of weight loss compared to the control. In addition, the effect was better when sucrose was added to STS. The treatment of STS at 0.4 mM + 50 g 1-1 sucrose was the best one. l -MCP treatment prolonged the vase life and lowered the percentage of weight loss at any level compared with untreated control. The best treatment in this concern was l -MCP at 0.5 g m-3 for 6h. The chlorophyll content (chl.a and chid)) of the leaves for the best treatment of each chemical was higher than the control. The treatment of STS at 0.4 mM + 50 g 1-1 sucrose gave the best results in this respect.

Cut 'Patumma' flowers normally last 10-15d when placed in clean water. 'Patumma' vase life is generally defined by when the coma bracts have discoloured or stems have wilted. A rapid decrease in water uptake within four days after harvest may trigger the withering of the stem. A preliminary vase life experiment with treatments of a solution containing plant growth regulators, gibberellic acid (GA 3 ) and benzyladenine (BA), delayed the withering and collapsing of stem. A pulsing treatment with 1 mM silver thiosulphate (STS) for less than one hour, increased the number of opened flowers, but had no significant influence on the inflorescence longevity. The chemicals used in this study had no effects either on prolonging the vase life or increasing 'Patumma' flower opening; indeed some treatments actually caused inflorescence stems to collapse earlier.

SummaryPost-harvest longevity of Epidendrum ibaguense cut flowers was maximum when treated for 6 h with 1 g m–3 Ethylbloc® [0.14% 1-methylcyclopropene; 1-MCP] followed, or not, by pulsing with 200 g l–1 sucrose for 12 h. This extended the vase-life from 5.5 d to at least 11 d. Cut inflorescences pulsed with 2.0 mM silver thiosulphate (STS) had reduced abscission of flowers, similar to the effect of 1-MCP. When inflorescences were pulsed with 200 g l–1 sucrose alone for 12 h, no effect was observed on the vase-life of the flowers. Flowers kept in a vase solution containing 20 g l–1 sucrose, 150 mg l–1 citric acid, and 200 mg l–1 8-hydroxyquinoline citrate did not influence the longevity of 1-MCP or STS pre-treated flowers, but the vase solution had a small influence on retarding abscission compared with flowers kept in distilled water. Adding 0.2 mM STS to the vase solution improved vase-life 1.74- and 1.45-fold compared with the longevity of flowers kept in distilled water or in vase solution alone, respectively. The presence of 0.3 mM AgNO3 alone, or mixed into the vase solution, had no affect on the vase-life of the flowers.

Cut flowers of Chrysanthemum morifolium RAM cv. Suny Reagan were treated with different concentrations of 8- hydroxyquinoline sulfate (8-HQS), silver thiosulfate (STS) and 1-methylcyclopropene (1-MCP) in order to improve the post production quality. 8-HQS was used at 200 and 400 ppm with or without sucrose at 50 O. STS was used at 0.2, and 0.4 mM with or without sucrose at 50 g/1 1-MCP was used at 0.3, 0.5 and 0.7 g/m3 for 6h.&#x0D; All the treatments of 8-HQS prolonged the vase life and minimized the percentage of weight loss of chrysanthemum cut flowers compared to the control. The vase life was larger when sucrose not combined with 8-HQS. The best treatment of 8-1-IQS was 400 ppm 8-HQS without sucrose. STS treatment led to prolong the vase life and minimized the percentage of weight loss comparing to the control. In addition, the effect was better when sucroseas was added to STS. The treatment of STS at 0.4 mM + 50 g/I sucrose was the best one. 1-MCP treatment increased the vase life and lowered the percentage of weight loss at any level comparing with untreated control. The best treatment in this concern was 1-MCP at 0.5 g/m3 for 6h. The chlorophyll content (chl.a and chl.b) of the leaves for the best treatment of each chemical was higher than that of the control. The treatment of 1-MCP at 0.5 g/m3 6h gave the best results in this respect.