Cut Gerbera Research Articles

The effects of supplemental nitrogen and calcium on the quality and postharvest life of cut gerbera

Abstract The objective of the present work was to evaluate the effect of nitrogen (N) and calcium (Ca), complementary to the complete fertilization established, on production, quality and postharvest shelf life of floral stems of gerbera as cut flower harvested 117 days after transplant. The experiment consisted of a combination of three doses of N.L−1 substrate (0.07 g, 0.15 g and 0.2 g) and three doses of Ca.L−1 substrate (0.02 g; 0.03 g and 0.04 g) and was conducted in a greenhouse in a bifactorial arrangement with an additional control treatment. Control plants were not supplemented with N or Ca. Both elements were diluted in water and applied manually every 15 days. Highest flower yields were obtained with application 0.2 g de N.L−1 substrate and 0.04 g Ca.L−1 substrate. Stem length, stem diameter, flower diameter, and longevity, relative fresh weight and solution uptake were highest in gerbera fertilized with 0.2 g de N.L−1 substrate and 0.04 g Ca.L−1 substrate. Applying every 15 days, 0.2 g of N.L−1 substrate and 0.04 g of Ca.L−1 substrate resulted in higher yields, better quality and postharvest shelf life of floral stems of gerbera as cut flower harvested 117 days after transplant.

Transcriptome profiling of Gerbera hybrida reveals that stem bending is caused by water stress and regulation of abscisic acid

BackgroundGerbera hybrida is one of the most popular cut flowers in the world; however, stem bending, which always happens when gerbera flower harvested from the field, greatly limits its vase life. To date the molecular mechanisms underlying stem bending remain poorly understood.ResultsIn this study, we performed high-throughput transcriptome sequencing of gerbera during stem bending using the Illumina sequencing technology. Three cDNA libraries constructed from mRNAs of gerbera stem at stem bending stage 0, 2 and 4 were sequenced. More than 300 million high-quality reads were generated and assembled into 96,492 unigenes. Among them, 34,166 unigenes were functionally annotated based on similarity search with known protein. Sequences derived from plants at different stem bending stages were mapped to the assembled transcriptome, and 9,406 differentially expressed genes (DEGs) were identified. Through Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, specific pathways were identified during the stem bending process, such as phenylpropanoid biosynthesis pathway, phenylalanine metabolism pathway, starch and sucrose metabolism pathway, and plant hormone signal transduction pathway. A total of 211 transcription factors (TFs), including TF families involved in plant senescence, such as NAC, MYB, WRKY, and AP2/ERF members, as well as TFs related to water stress tolerance, were shown to be regulated during stem bending. Gene Onotology (GO) functional enrichment analysis indicated that key genes involved in responses to osmotic and oxidative stresses were also varied in expression during this process. Furthermore, analysis of DEGs involved in the hormone signaling pathways and determination of endogenous abscisic acid (ABA) content showed that stem bending may be an ethylene-independent process, but regulated by ABA. In short, our findings suggested that the stem bending of cut gerbera may be caused by the involvement of water stress and regulation of ABA during the postharvest life.ConclusionsThe transcriptome sequences provide a valuable resource in revealing the molecular mechanism underlying stem bending of cut flower and offer novel genes that can be used to guide future studies for ornamental plant breeding.

Light-emitting Diodes Can Replace High-pressure Sodium Lighting for Cut Gerbera Production

A greenhouse study was undertaken to investigate whether light-emitting diode (LED) technology can be used to replace high-pressure sodium (HPS) lighting for cut gerbera production during Canada’s traditional supplemental lighting (SL) season (November to March). The study was carried out at the University of Guelph’s research greenhouse, using concurrent replications of SL treatments within the same growing environment. LED (85% red, 15% blue) and HPS treatment plots were set up to provide equal amounts of supplemental photosynthetically active radiation (PAR) at bench level. This setup was used to assess the production of three cultivars of cut gerbera (Gerbera jamesonii H. Bolus ex Hook.f): Acapulco, Heatwave, and Terra Saffier. There were no treatment differences in SL intensity, with average SL photosynthetic photon flux density (PPFD) and daily light integral (DLI) of 55.9 µmol·m−2·s−1 and 2.3 mol·m−2·d−1, respectively. Flowers harvested from the LED treatment had a 1.9% larger flower diameter in ‘Acapulco’; 4.2% shorter and 3.8% longer stems in ‘Heatwave’ and ‘Terra Saffier’, respectively; and 7.7% and 8.6% higher fresh weights for ‘Acapulco’ and ‘Terra Saffier’, respectively, compared with flowers harvested from the HPS treatment. There were no differences in accumulated total or marketable flower harvests for any of the cultivars. The vase life of ‘Acapulco’ flowers grown under the LED treatment was 2.7 d longer than those grown under the HPS treatment, but there were no SL treatment effects on water uptake for any of the cultivars during the vase life trials. There were no SL treatment effects on specific leaf area for any of the cultivars. There were only minimal treatment differences in leaf, soil, and air temperatures. Cut gerbera crops grown with under LED SL had equivalent or better production and crop quality metrics compared with crops grown under HPS SL.

The Effects of Bacteria in Vase Water on the Vase Life of Cut Gerbera Cultivars

The Effects of Bacteria in Vase Water on the Vase Life of Cut Gerbera Cultivars

Salicylic acid modulates cutting-induced physiological and biochemical responses to delay senescence in two gerbera cultivars

The postharvest longevity of gerbera (Gerbera jamesonii) flowers has a critical importance in determining their commercial value; and therefore, there is a commercial demand for prolonging their vase life (VL). Here, we tested the efficacy of salicylic acid (SA, 150 µM) preservative in extending longevity of cut flower of two gerbera cultivars, namely the ‘Sunway’ and ‘Bayadere’, of which water-held ‘Bayadere’ has longer VL than water-held ‘Sunway’. The results indicated that exogenous SA could significantly prolong the VL of cut flowers of both ‘Sunway’ and ‘Bayadere’ cultivars, with better preservative effect being observed on ‘Sunway’. SA preservative was more effective in ameliorating relative water uptake and relative fresh weight in ‘Sunway’ than in ‘Bayadere’, which was accompanied by a greater decrease in proline accumulation. Application of SA prolonged the VL of two cut gerbera flower cultivars by inhibiting the activity of polyphenol oxidase involved in browning reaction, and decreasing oxidative stress through improving reactive oxygen species-scavenging antioxidant capacity, which included accumulation of total phenolic compounds and total flavonoids, and enhancement of enzymatic antioxidant activities. As a result, membrane lipid peroxidation levels were reduced in cut flowers of both cultivars, with higher reduction level being observed in ‘Sunway’ than in ‘Bayadere’. Additionally, SA preservative was more efficient in maintaining a greater content of total soluble proteins in ‘Sunway’ than in ‘Bayadere’. These findings clearly demonstrated that SA has higher preservative effects on extending VL of ‘Sunway’ than that of ‘Bayadere’. Taken together, SA can be recommended to farmers for postharvest treatments to maintain quality and delay senescence of gerbera flowers.

Genetic engineering of lignin biosynthesis pathway improved stem bending disorder in cut gerbera (Gerbera jamesonii) flowers

Gerbera (Gerbera jamesonii) is an important commercial species of cut flowers all around the world. Stem bending is a major disorder in cut gerbera flowers caused mainly by the lack of mechanical support in the flower stem. Lignin is the component of plant cell walls that provides strength. Three major enzymes comprise the pathway of lignin anabolism including peroxidase (POD), cinnamyl alcohol dehydrogenase (CAD), and cinnamoyl-CoA reductase (CCR). In this study, three overexpressed mutants for each of these major genes were generated and analyzed for their role in stem bending. Comparing the pod transgenic plants with ccr and cad mutants indicated that pod plants had the highest lignin content. Compared to wild-type (WT) plants, the highest vase life, membrane stability and solution uptake were obtained in gerbera pod mutants. Therefore, it appears that higher lignin contents can decrease stem bending and improve cell wall rigidity of cut gerbera flowers. These results also suggest that POD is a key gene in the biosynthesis of lignin in gerbera.

Effects of nano-silver pulsing, calcium sulfate and gibberellin on an antioxidant molecule and vase life of cut gerbera flowers

Abstract: The aim of this study was to evaluate interactions between NS coupled with CS and GA on flavonoid, cell membrane behavior and extending the vase life of cut gerbera. Pulse treatments of flowers in NS at concentrations 0 (DI), 3 or 9 mg/l for 24 h. Then, flowers were treated with preservative solutions containing calcium sulfate (0, 10 or 20 mM) and GA 4+7 (0 or 20 mg/l), plus 1.5% sucrose in all preservative solutions. Pulse treatments with 3 or 9 mg NS/l and holding in solution containing 20 mM CS compared to the control treatment (holding in the solution of sucrose following pulse treatment in DI) significantly extended vase life by 8 days. According to the antioxidant role of flavonoids, and lower amounts of flavonoid in the flowers that pre-treated with NS, therefore, it may be said that NS prevented from microbial attack.

Correlation between Calcium and Pectin Contents in Cut Gerbera During Scape Bending

Correlation between Calcium and Pectin Contents in Cut Gerbera During Scape Bending

Postharvest life of cut gerbera flowers as affected by salicylic acid and citric acid

Postharvest life of cut gerbera flowers as affected by salicylic acid and citric acid

Postharvest Longevity of Cut Gerbera and Alstroemeria as Affected by Citric Acid Pulse and Vase Solutions

End-user vase life of two popular cut flowers, gerbera (Gerbera jamesonii) and alstroemeria (Alstroemeria spp.) is limited due to non-adoption of appropriate postharvest treatments in Sri Lanka. Citric acid-based cut flower preservatives could be affordable treatments to extend the longevity of those species. Therefore, a study was carried out to investigate the effectiveness of pulse and vase solution treatments with citric acid for increasing the keeping quality of cut gerbera and alstroemeria flowers. For pulsing, cut flower stems were treated with 0 mM (distilled water), 5, 10 and 15 mM citric acid combined with 5, 16 and 24 h pulsing durations. Only alstroemeria was further tested with 0, 15, 25 and 30 mM citric acid with previous pulsing durations. Pulsed stems were stood into distilled water for vase life evaluation. For vase solution treatment, citric acid at 0, 1, 2, 5 and 10 mM concentrations were incorporated in vase water. In the next step, two levels of citric acid (0, 1 mM) were combined with four levels of sucrose (0, 1, 2, 5%) in vase water for gerbera. Factorial experiments were arranged in completely randomized design with five to ten replicates. Data on vase life, relative fresh weight and solution uptake rate were recorded. Pulse treatments were ineffective for improving vase life. Nevertheless, a vase solution with 1 mM citric acid showed a 2-fold increase in vase life and a better retention of fresh weight in cut gerbera. Incorporation of citric acid in vase water did not extend the vase life of cut alstroemeria flowers. Combining citric acid with sugar in the vase solution maintained favourable relative fresh weight, water uptake rates and vase life in cut gerbera. Thus, incorporation of 1 mM citric acid and 1 – 2 % sugar in vase or holding solutions could improve the longevity of cut gerbera flowers.

Effects of Pre- and Postharvest Treatments of Silicon and Rice Hull Ash on Vase Life of Gerbera

This study was conducted to investigate the effects of different silicon supplements and postharvest treatments on growth and yield of gerbera in a greenhouse experiment. Silicon supplements were including potassium silicate at three concentrations (0, 140 and 200 mg L−1), sodium silicate at three concentrations (0, 50 and 100 mg L−1) and rice hull ash (RHA) at three concentrations (0, 50 and 100 mg L−1). Also, postharvest treatments were including sucrose, salicylic acid (200 and 400 mg L−1), methyl jasmonate (15 and 25 mg L−1) and distilled water (as control). The application of potassium silicate, RHA and sodium silicate led to decrease in dry weight of flower. Shoot length and diameter were substantially higher in 140 mg L−1 potassium silicate than those in control treatment. The maximum inflorescence diameter was observed in rice husk ash (50 mg L−1). Capitulum diameter was far greater in sodium silicate at 50 mg L−1 compared to other treatments. Vase life of gerbera flower was greater in 400 mg L−1 salicylic acid and 15 mg L−1 methyl jasmonate than in control treatment. The maximum inflorescence diameter was observed in 400 mg L−1 salicylic acid. This study confirmed that the studied sources of Si, salicylic acid and methyl jasmonate increased marketable quality of cut gerbera flowers.

Organic Composition Analysis and Anatomical Observation in Cut Gerbera (Gerbera jamesonii Bolus) during the Peduncle Elongation Stages

Organic Composition Analysis and Anatomical Observation in Cut Gerbera (Gerbera jamesonii Bolus) during the Peduncle Elongation Stages

Effect of Floral Preservatives on Vase Life of Gerbera Cut (Gerbera jamesoniiL.) cv. “Dana Allen”

The present study, conducted in the Department of Horticulture, J.A.U., Junagadh (India) was aimed to assess the effect of floral preservatives on the vase life of cut gerbera (Gerbera jamesonii L.) cv. ‘Dana Allen’. The experiment was laid out in a completely randomized design with three replications and nineteen treatment-combination comprising of five floral preservatives viz., sucrose (2 and 3%), 8-HQC [8-hydroxy quinoline citrate] (150 and 200 mg L−1), Al2SO4 (25 and 50 mg L−1), AgNO3 (15 and 25 mg L−1) and Co(NO3)2 (180 and 270 mg L−1) along with an untreated control. The vase solution of 8-HQC @ 200 mg L−1 + 2% sucrose enhanced all the qualitative parameters and improved vase life of gerbera. The vase life could be extended upto 13.6 days of cut gerbera. This treatment improved fresh flower weight by 112.3, 104.2, 88.2, 67.1% on 3, 6, 9 and 12th day of vase, respectively. The treatment of 8-HQC @ 200 mg L−1 + 2% sucrose resulted in maximum total solution uptake (61.26 mL), flower diameter on 3rd day of vase (11.39 cm) and 50% opening of disc florets (7.28 days), 75% opening of disc florets (8.95 days) and 100% opening of disc florets (11.52 days) in gerbera. It may be concluded that holding solution of 8-HQC along with sucrose may help in extending the vase life of gerbera cut flowers.

Extending the Vase Life of Cut Gerbera (Gerbera jamesonii Bolus ex. Hook) cv. Savannah by Using Locally Available Floral Preservatives under Ambient Storage

A laboratory trial was carried out to investigate the effectiveness of different locally available floral preservatives on extension of vase life of cut gerbera cv. Savannah under ambient storage condition. All the cut gerberas were precooled at 5°C for 6 hours and followed by pulsing with sucrose at 20%+sodium hypochlorite at 50 ppm for 12 hours and then kept in locally available preservative floral solutions i.e. sugar, commercial vinegar, lime (Citrus aurantifolia) juice, commercial bleach (calcium hypochlorite-CaOCl2) and neem (Azadirachta indica) extract at different concentrations in combination with 4% sucrose. Using the solution of neem extract at 1% coupled with 4% sucrose significantly maintained water relations and reduced scape bending curvature as compared to all other treatments. Total soluble solids in flower stalk and anthocyanin content in ligules of cut gerberas kept in neem extract at 1%+4% sucrose solution were also highest i.e. (10.08°Brix) and (5.83 mg Congo Red g−1 f wt) respectively. The cut gerberas held in solution of neem extract at 1%+sucrose at 4% recorded lowest optical density (0.041) which was attributed with lowest microbial count (4.26×105 cfu ml−1) and resulted in highest vase life (11.76 days) compared to control (4.53 days) which recorded highest microbial count (8.99×106 cfu ml−1).

Vase-life of Gerbera jamesonii Bolus cut flowers depending upon; media, mineral nutrition, their morphological attributes and treatment with flower preservative

The correlations among different media, mineral nutrition and morphological features of gerbera flowers in relation to their vase-life period investigated. The bast medium for longevity of cut gerbera flowers was the mixture of composted pine bark and peat moss fertilized with N – 250 mg/1 and Mg – 150 mg/1. It was found that cut gerberas lasted longer when they were the Alkemade type, i.e. with wide petals. Yellow flowers remained fresh longer than red and pink ones. It was also found that the vase-life period of gerberas directly correlated with the length of floral stalk, its ability to grow and the inflorescence diameter. The solution of flower preservative Proflovit-72 was effective 'in extending life at room temperature and improved the quality and longevity of flowers which were previously in coldstorage for 1 to 3 weeks.

Postharvest Life of Cut Gerbera (Gerbera jamesonii) as Affected by Nano-silver Particles and Calcium Chloride

The purpose of this study was to evaluate the effects of Nano-silver (NS), calcium chloride (CaCl2) and their combinations on Gerbera jamesonii ‘Carambole’ cut flowers. The experiment was conducted as a completely randomized design (CRD) with 10 treatments and four replications, with three flowers in each replication. Treatments consisted of 5 mg L-1 NS, 1% and 2% CaCl2, 5 mg L-1 NS+ 1% CaCl2, 5 mg L-1 NS + 2% CaCl2, 0.1% and 0.2% CaCl2, 5 mg L-1 NS + 0.1% CaCl2, 5 mg L-1 NS + 0.2% CaCl2 and a control. It was revealed that CaCl2 postharvest spray, NS in a vase solution, as well as their combinations could significantly increase the vase life of gerbera flowers. The longest postharvest life of treated flowers was obtained from 5 mg L-1 NS and 5 mg L-1 NS + 1% CaCl2 treatments. The highest solution uptake was observed in 5 mg L-1 NS, 5 mg L-1 NS + 2% CaCl2 and 5 mg L-1 NS +1% CaCl2 treatments. Furthermore, application of NS and CaCl2 resulted in a reduced loss of relative fresh weight. The application of CaCl2 alone was able to increase all mentioned traits; however, this increase was less than 5 mg L-1 NS, 5 mg L-1 NS + 1% CaCl2 and 5 mg L-1 NS + 2% CaCl2 treatments. Additionally, in vitro cultivation and microscopic counting of microorganisms showed that microorganism growth at the end of flowering stems had been largely restricted by using NS solely or in combination with CaCl2.

화경 기부의 절단 길이와 수확 후 물올림 시기가 거베라의 절화수명에 미치는 영향

화경 기부의 절단 길이와 수확 후 물올림 시기가 거베라의 절화수명에 미치는 영향

Stem bending in cut Gerbera jamesonii flowers: Effects of a pulse treatment with sucrose and calcium ions

The vase life of cut Gerbera flowers (Gerbera jamesonii cv. Tamara) is often short due to stem bending. The purpose of this study was to find a pulse treatment, to be applied directly after harvest, which would delay this bending. Bending was hypothesized to be due, at least in part, to a xylem blockage by bacteria (leading to early turgor loss), to lack of osmotic pressure, and to lack of cell wall stiffness. Chemicals tested included antimicrobial compounds, surfactants (to bypass xylem occlusion), sugars, inorganic ions, and chemicals affecting cell wall rigidity. When used as a pulse treatment, antimicrobial compounds such as chlorine and silver ions had no effect. Only a buffer at pH 3.0–3.5, which inhibits bacterial growth, delayed bending. A range of surfactants tested, many of which had antimicrobial activity, had no effect. Sugars delayed the time to bending, if accompanied by an efficient antimicrobial compound. Cell wall rigidity can be affected by calcium ions and H+ concentration. Treatment with calcium chloride delayed bending. Vanadate, an inhibitor of H+ transport to the cell wall, almost completely prevented stem bending, but resulted in unwanted petal discoloration. By contrast, fusicoccin, a promoter of H+ transport to cell walls, drastically hastened bending. A mixture of chemicals (50mM calcium chloride, 25gL−1 sucrose, buffered at pH 3.5 by citric acid and K2HPO4) was satisfactory as a 24h pulse treatment, prior to 24h of dry storage at 20°C and vase life at 20°C. It delayed the time to bending during vase life in cv. Tamara and six other cultivars tested which are prone to stem bending.

The First Report of Tomato spotted wilt virus on Gerbera and Chrysanthemun in Venezuela.

Gerbera (Gerbera jamesonii) and Chrysanthemum (family Asteraceae) are two of the top 10 cut flowers of the world, with great commercial value. Since 1998, Venezuela began a floral industry to produce and export fresh cut gerbera and chrysanthemum, with 40% of nurseries concentrated in Altos Mirandinos (Miranda State, north central region of the country). For the past 2 years, greenhouse-grown gerbera and chrysanthemum have been observed displaying symptoms resembling those associated with tospoviruses. Symptomatic plants showed concentric rings, irregular chlorotic blotches, and deformation on leaves. Disease incidence was estimated at 30%. Mechanical inoculation with extracts of symptomatic leaves reproduced the typical concentric ring symptoms on indicator plants Arachis hypogaea L. cv. San Martín, Capsicum chinense, and G. jamesonii 6 to 15 days after inoculation. In initial tests, leaves from each 30 symptomatic gerbera and chrysanthemum species from several greenhouse facilities in Altos Mirandinos reacted positively when tested by DAS-ELISA with polyclonal antisera (ATCC, Rockville, MD) raised against Tomato spotted wilt virus (TSWV). Total RNA was extracted with the RNeasy Plant Mini kit (QIAGEN, Hilden, Germany) from two gerbera and two chrysanthemum ELISA-positive samples. The TSWV coat protein gene was amplified by conventional reverse transcription (RT)-PCR using primers CP1 TSWV (TTAACTTACAGCTGCTTT) and CP2 TSWV (CAAAGCATATAAGAACTT) (1). A single DNA product of ~823 bp was amplified from all samples. RT-PCR products were directly sequenced in both orientations and sequences were deposited in GenBank (Accession Nos. KF146700 and KF146701 derived from chrysanthemum, KF146702 and KF146703 derived from gerbera). The resulting sequences showed over 99% identity with each other. and were found to be closely related (over 99%) with TSWV isolates deposited in GenBank originating from different hosts from France (FR693058, FR693055), Montenegro (GU339506, GU339508, GU355940), Italy (HQ830187), New Zealand (KC494501), South Korea (KC261967), and the United States (AY744476). To our knowledge, this is the first confirmed report of TSWV infecting gerbera and chrysanthemum in Venezuela. The relatively widespread occurrence of TSWV in Miranda State underscores the need for systematic surveys to assess its incidence and impact on ornamental crops so that appropriate management tactics can be developed. Reference: (1) R. A. Mumford et al. J. Virol. Methods 57:109, 1996.

Effect of antimicrobial compounds on cut Gerbera flowers: Poor relation between stem bending and numbers of bacteria in the vase water

Gerbera flowers (Gerbera jamesonii) often show stem bending. In four cultivars (Tamara, Liesbeth, Cora, and Mickey), we tested the effects on bending of antimicrobial compounds (chlorine bleach, a slow release chlorine compound, 8-hydroxyquinoline citrate [HQC], silver nitrate, carvacrol and thymol), some combined with sugars. At concentrations used for other cut flowers, inclusion in the vase solution of several of the antimicrobial compounds delayed bending, had no effect, or hastened bending. Hastening of bending was found at higher concentrations. It was accompanied with visible damage on the stem ends. Results with HQC indicated high toxicity as it did not delay bending at any of the concentration tested (100–400mgL−1). At 200mgL−1 HQC induced growth of bacteria that were not found in the controls. The number of bacteria in the vase water showed a low correlation with bending. Visible toxicity on the stem surface was often associated with a high bacteria count. However, at relatively high concentrations of the antimicrobial compounds stem bending was associated with a low count. This indicated an effect other than bacteria. Water uptake was low in stems that bent early. It is hypothesized that material from dead stem cells resulted in a xylem blockage which led to early bending. Sucrose at 15gL−1 in combination with an antimicrobial compound (slow release chlorine, HQC) resulted in the absence of stem damage and produced much less bending than the same concentration of the antimicrobial compounds alone. Sucrose apparently counteracted the toxic effects of the antimicrobial chemicals.