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In the floriculture trade, cut pepper (Capsicum annuum) stems are typically grown for their fruit to add color contrast to the foliage and blossoms of conventional floral arrangements. Stems are commonly stripped of foliage because leaves wilt rapidly. Three divergent plant types and commercial hydration protection spray products were evaluated to identify effective vase life treatments and new pepper lines that combine both fruit and foliar interest with an acceptable postharvest cut stem life. Three inbred US Department of Agriculture pepper breeding lines with a tall vigorous growth habit and black foliage were selected for evaluation as cut stems. Line 190-2 produced upright, tabasco-like fruit; 191-1 produced upright, clustered, round fruit; and 196-1 was fruitless. Three commercial spray treatments Crowning Glory (FLCG), Finishing Touch, and Aqua Finish Clear (AFC) were evaluated on treated cut stems stored at 10 and 23 °C. The pepper breeding line had the greatest influence on cut stem foliage and fruit vase life. The fruitless line, 196-1 exhibited an extended vase life in comparison with fruited lines. Cold storage extended the vase life of cut stems. FLCG reduced foliage vase life at 23 °C, and AFC extended foliage vase life of the fruitless line 196-1. Relative to foliage, fruit exhibited greater resistance to desiccation, with glossier fruit of 191-1 desiccating more rapidly than fruit of 190-2. Similar trends were noted when cut stems were stored at 10 °C for 7 days and moved to 23 °C. However, in 2022 trials, the vase life of 190-2 was shortened, and those of 191-1 and 196-1 were extended, highlighting the influence of preharvest factors on vase life. The results demonstrate that cut stems of new pepper lines with vigorous upright growth habits and black-pigmented foliage, together with diverse fruit morphology, provide innovative possibilities for stunning cut flower arrangements.

Highlights • Nano-silver pretreatment extended vase life of cut gardenia foliage. • Nano-silver pretreatment delayed wilting of cut gardenia foliage. • Nano-silver pretreatment improved water relations of cut gardenia foliage. • Nano-silver pretreatment inhibited bacterial xylem blockage of cut gardenia foliage. • Nano-silver mostly remained in stem-ends where it exerted its antibacterial effect. Abstract Gardenias (Gardenia jasminoides Ellis var. 'fortuniana') have commercial importance as cut foliage but are prone to severe postharvest water deficit and quick wilting. Herein, we investigated the efficacy of pretreatment with nano-silver (NS), a strong antibacterial agent, in enhancing water relations and the vase life of cut gardenia foliage. Compared with the deionized-water controls, pretreatment with NS at 10, 15, 20, 25, or 30 mg L−1 for 24 h significantly extended the vase life of cut gardenias. The most effective NS concentration was 15 mg L−1, which promoted the longest (15.2 days) vase life extension, i.e., 310.2% of that of the control treatment. In addition, pretreatment with 15 mg L−1 NS effectively delayed wilting by maintaining a higher water balance value and relative fresh weight when compared with untreated cut foliage. Scanning electron microscopy revealed that these higher values were due to an improved water uptake as a result of the alleviation of bacterial xylem blockage at the stem-ends. Furthermore, Ag concentration was remarkably higher at the stem-ends of NS-pretreated cut gardenias than in any other tissues. Overall, these results demonstrate that NS pretreatment effectively inhibited bacterial growth at the cut stem-ends, and helped maintain a favorable water balance, thereby delaying wilting and extending the vase life of cut gardenias. [ABSTRACT FROM AUTHOR]

Florists’ greens are becoming increasingly important in contemporary floristry. Numerous studies conducted on cut flowers have led to the development of technologies for their post-harvest handling; however, in the case of florists’ greens they are still insufficient. Moreover, the extensive range of florists’ greens lacks leaves and the leafy culms of grasses. The aim of this study was to determine the post-harvest longevity of the leaves and leafy culms of ornamental grasses conditioned in water solutions of gibberellic acid and 8-hydroxyquinoline sulphate. The post-harvest longevity of leaves was examined in cultivars of the following species: Glyceria maxima Hartm. ‘Variegata’, Miscanthus sinensis Thunb. ‘Zebrinus’ and Spartina pectinata Link. ‘Aureomarginata’. The post-harvest longevity of leafy culms was investigated in Alopecurus pratensis L. ‘Aureovariegatus’, Chasmanthium latifolium Michx., Miscanthus sinensis Thunb. ‘Silberspinne’, Pennisetum alopecuroides L. and Phalaris arundinacea L. ‘Picta’. Conditioning in gibberellic acid had a positive effect on the post-harvest longevity and fresh weight loss and the index of leaf greenness of leaves in the case of Miscanthus sinensis ‘Zebrinus’, while conditioning in 8-hydroxyquinoline sulphate improved fresh weight loss and the index of leaf greenness of the leafy culms of Miscanthus sinensis ‘Zebrinus’, Pennisetum alopecuroides and the leaves of Glyceria maxima ‘Variegata’.

The leaves of Zantedeschia and Hosta are used as florist greens in different floral arrangements. The most efficient postharvest treatment for cut foliage is the use of growth regulators, which prolong their vase life by delaying degradative changes occurring in leaves, especially proteolysis. Cycloheximide (CHI) is one of the protein synthesis inhibitors, blocking the enzymes responsible for decreasing membrane integrity, a phenomenon hastening senescence. The aim of this experiment was to evaluate the effects of CHI and benzyladenine (BA) or gibberellic acid (GA3) on the longevity of cut foliage in hosta (Hosta sp.) cultivars and Ethiopian calla (Zantedeschia aethiopica) and to follow the changes in certain proteolytic processes occurring during senescence. Generally, 24 h conditioning with cycloheximide shortened the longevity of cut calla leaves while having no effect on hosta vase life. In ageing leaves of ‘Minima Glauca’ hosta and calla, the total proteolytic activity increased, including that of cysteine protease. Due to the application of BA or GA3 in hosta and calla, respectively, this activity was limited. On the contrary, the use of CHI either did not affect the activity of cysteine protease or increased it several-fold relative to the control, in hosta and calla, respectively. Leaves treated with growth regulators had many more soluble proteins and fewer free amino acids, including free proline, than leaves from other treatments. The highest free proline level was determined in calla leaves conditioned with CHI, where it increased 18-fold relative to the initial level.

Acacia holosericeais a novel cut foliage line with a short vase life. Postharvest application of salicylic acid (SA) can extend the vase life of cut flower. SA is a host defence inducer, as is jasmonic acid (JA). SA and JA were compared as vase solution additives forA. holosericea. Three experiments were conducted that also compared these two chemicals with H+and Cu2+as known vase life extending additives. Vase solutions containing SA at 0.5, 1.5, and 2.5 mM gave ~1.3- to 1.5-fold vase life extensions as compared with the distilled water (DW; control). Provision of Cu2+and JA at 0.5 mM in vase solutions also prolonged vase life by ~1.3-fold as compared with DW. The positive effect of SA tended to be greater than that of JA, but was inferior to that of Cu2+at the same concentration. However, trend differences among these treatments were not statistically significant. CutA. holosericeafoliage stems treated with SA and JA exhibited higher relative fresh weight (RFW) and vase solution uptake rates as compared with DW. Overall, SA and JA evidently extended the vase life of cutA. holosericeafoliage by inhibiting water loss and maintaining RFW during the vase period. [ABSTRACT FROM AUTHOR]

Camellias are potentially appreciated as cut branches due to their deep and bright green foliage with a high number of flower buds. The present research investigated the role of ethylene in postharvest flower and leaf abscission of seven cultivars of Camellia japonica and evaluated the effect of inhibitors of ethylene action on their vase life. Cut flowering branches were shipped from private companies, mimicking a long and short supply chain. Plant materials were treated with commercial Chrysal, gaseous 1-MCP, and 1-MCP included in β-cyclodextrin-based nanosponges and compared to cut branches exposed to exogenous ethylene (1 ± 0.2 μl l-1) for 24 h and control in tap water. Visual checks for symptoms of variation in senescence, flower opening stage, flower abscission, leaf chlorophyll content (SPAD) and gloss, in addition to ethylene production levels were monitored daily. Cut branches placed in tap water lost ornamental value after ca 5.5 days of vase life and reached complete senescence after about 10 days in all the studied cultivars, regardless of supply chain, with the exception of 'Il Tramonto' with 10 and 20 days, respectively. Exogenous ethylene application reduced camellia cut branch longevity in 'Debbie' and 'R.H. Wheeler', while the other cultivars lasted as long as the control. Anti-ethylene treatments prolonged the vase life only in 'Korun Koku' and 'Il Tramonto'. [ABSTRACT FROM AUTHOR]

Reducing effects of exogenous hydrogen peroxide on leaf rolling in detached leaves of Ctenanthe setosa were studied. The leaves were kept in HO solutions ranging from 0 to 1 mM for 48 h and then, osmotic stress was applied for 4 h by polyethylene glycol (PEG). Degree of leaf rolling, loss of leaf water, and malondialdehyde (MDA) content were reduced by 0.2 mM HO. Antioxidant enzymes were induced by 0.2 mM HO. Endogenous HO content was increased after the 0.5 and 1 mM HO treatments but was decreased after 0.2 mM HO treatment. Proline was decreased after exogenous HO applications. Total soluble sugar content was increased as compared to the control after 0.2 mM HO treatment. In conclusion, low-dose exogenous HO treatment could delay leaf rolling by inducing tolerance to osmotic stress due to modulation of the antioxidant system, soluble sugar accumulation, and maintenance of leaf hydration. Therefore, postharvest life of C. setosa cut foliage could be extended by 0.2 mM HO treatments. [ABSTRACT FROM AUTHOR]

Abstract: The mechanisms of action of Cu2+ in improving the longevity of cut flowers and foliage have not been elucidated. Possible antimicrobial action of Cu2+ against stem end and vase solution colonising bacteria was investigated using Cu2+ treatments optimised for cut Acacia holosericea A. Cunn. ex G. Don foliage stems. These treatments were a 5h pulse with 2.2mM Cu2+ or a 0.5mM Cu2+ vase solution versus a deionised water (no Cu2+) control. Bacterial growth over time was assessed by a standard plate count agar technique and with scanning electron microscopy. Cu2+ treatments significantly extended the cut foliage vase life. However, they did not have sustained antibacterial activity against stem end or vase solution colonising bacteria. Also, regular recutting of 1–2cm from the stem ends did not substantially improve either cut stem water relations or longevity. The positive effects of Cu2+ treatments were unaffected by the repeated stem end recutting. It was concluded that the primary mechanism of Cu2+ was not antibacterial. Moreover, naturally growing vase solution and stem end microbial populations had relatively insignificant effects on cut A. holosericea vase life. Research into alternative mechanisms of Cu2+ is required. [Copyright &y& Elsevier]

Abstract: Dodonaea ‘Dana’ is an Israeli hybrid with purple tinted leaves, cultivated for cut foliage branches. Cut Dodonaea branches showed strong seasonal variations in longevity, wilting after one week in winter, while displaying a vase life of three weeks in summer. We examined the relationship between functional anatomy, including vessel, stomata and trichome densities, vessel member length and leaf thickness, and water status of cut branches during vase life over two consecutive seasons, in relation to the average monthly day temperature. All the vascular and leaf anatomy traits examined were significantly correlated with seasonal average monthly day temperature. On day one of vase life the branch water status was positively correlated with vessel, stomata, and trichome densities, and negatively correlated with vessel member length and leaf thickness. However, on day 16, the branch water status was negatively correlated only with vessel member length and diameter, implying different relative importance of anatomical parameters for surviving water stress in the vase. Our results suggest that Dodonaea ‘Dana’ branches exhibit a strong interconnection between environmental parameters and postharvest performance, showing temperature-related seasonal anatomical changes, which lead to differential hydraulic performance during vase life. [Copyright &y& Elsevier]

Abstract: Cut Rosa hybrida cv. High & Mighty flowers and Acacia holosericea (Velvet Leaf Wattle) foliage were subjected to various physical stem-end treatments as practised by florists. Their effects on longevity (vase life) and water relations [relative fresh weight (RFW) and vase solution uptake (VSU)] were quantified. All vase water contained sodium dichloroisocyanurate (DICA) biocide. Bark removal had either positive or neutral effects on the vase life of fresh-cut rose and had either neutral or negative effects on fresh-cut acacia. Stem-end splitting had either no or negative effects on the vase life of fresh-cut rose and acacia. However, both bark removal and stem-end splitting increased the vase life of both species when applied after short term storage for 24h at 4°C. Crushing stems had no effect on the vase life of fresh-cut rose, but tends to increase the vase life of fresh-cut acacia. Hot water scalding either increased or had no effect on the vase lives of rose and acacia. The tendency for bark removal to increase vase life of fresh-cut rose was associated with better maintenance of RFW and sustained VSU. However, for the most part, stem-end treatments had typically negative or neutral effects on RFW of fresh-cut rose and acacia. Likewise, the treatments had mostly negative or neutral effects on VSU. Overall for both species, there is little or no benefit and potentially negative effects on vase life, RFW and VSU of applying stem-end treatments as sometimes advocated by florists. [ABSTRACT FROM AUTHOR]

Abstract: Insufficient water uptake by cut flowers and foliage species is often due to stem end occlusion and poor stem hydraulic conductance that involve bacterial growth and/or wound healing. S-carvone has putative antibacterial and anti-wound healing activity. S-carvone (0, 0.318 and 0.636mM) was evaluated as a vase solution for Acacia holosericea (Mimosaceae), Baeckea frutescens (Myrtaceae), Chamelaucium uncinatum cv. ‘Mullering Brook’ (Myrtaceae) and Chrysanthemum sp. cv. ‘Dark Splendid Reagan’ (Asteraceae). S-carvone was also tested in vitro for activity against a vase solution bacterium. S-carvone at 0.318 and 0.636mM showed significant (P <0.05) positive effects on relative fresh weight, solution uptake and/or vase life for B. frutescens foliage and C. uncinatum flowering stems, but did not have positive effects for A. holosericea and Chrysanthemum sp. S-carvone did not suppress vase solution bacterial populations. Moreover, there was no in vitro activity at vase solution concentrations against the specific vase water bacterium, Bacillus cereus. For the two Myrtaceous genotypes, B. frutescens and C. uncinatum, S-carvone apparently extended vase life by inhibiting wound healing. [Copyright &y& Elsevier]