Attractive local endemic plant species of biodiversity hotspots represent promising candidates for the introduction of novel horticultural crops, as the floricultural industry continuously seeks new ornamental products with unique features. This study investigated the postharvest performance of the cut inflorescences of Campanula pelviformis and Petromarula pinnata (Campanulaceae), two single-island endemic plants (Crete, Greece) with well-documented ornamental potential. Fifteen replicate cut inflorescences per treatment from two different populations of C. pelviformis and one population of P. pinnata were placed individually in vases containing three holding solutions (1% sucrose, FloraLife®, and deionized water). Vase life (VL) longevity and floral development were monitored daily, whereas inflorescence fresh weight and remaining solution percentage were recorded every two days. In addition, petal color parameters were assessed at three time points during the experimental period. The FloraLife® solution significantly increased VL (20.40 ± 0.87 days), fresh weight, and reduced remaining solution percentage in C. pelviformis, whereas untreated inflorescences resulted in the greatest VL in P. pinnata (19.87 ± 0.26 days), while increased fresh weight and decreased remaining solution percentage were observed by the 1% sucrose treatment. Flower open rate (FOR) final values and flower fall rate (FFR) values were higher in the untreated cut inflorescences of C. pelviformis (90.3% and 51.37%, respectively), while no significant effects were observed in those of P. pinnata (>78% and >41.37%, respectively). Over time, a gradual increase in FOR occurred in inflorescences of C. pelviformis with FloraLife® solution and in untreated ones of P. pinnata, while increases in FFR were also observed in the same treatments. Minimal changes in petal colour parameters were recorded in C. pelviformis inflorescences during the experimental period. These findings provided first-time evidence into the postharvest handling of the inflorescences of these local Cretan endemics, thus paving the way to their further valorization for the diversification of Mediterranean floriculture with unique phytogenetic resources.

The short vase life (VL) of gladiolus cut flowers reduces their commercial importance. Trehalose (Tre), a phyto-product that plays a unique role in plant functioning and environmental safety, can be used to improve VL. This work assessed a preharvest spray of Tre to mitigate postharvest (PHV) oxidative stress in "White Prosperity" gladiolus cut flowers and its physiological and PHV-related mechanisms. The treatments were 1 g L-1 (Tre1), 2 g L-1 (Tre2), and 3 g L-1 (Tre3), and a distilled water control. Foliar applied Tre3 (3 g L-1) improved VL. Trehalose spray improved ornamental traits, VL, and number of opened florets. Tre reduced oxidative injury to the membrane structure, as depicted by lower accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA), by increasing antioxidant defense system activities. Tre also influenced total soluble proteins, sugars, phenols, and proline contents as well as floral hormonal levels, including salicylic acid, abscisic acid, and ascorbic acid. Tre could improve plant health by influencing photosynthesis and increasing VL by enhancing sugars, osmoprotectants, and antioxidant capacity.

In this study, a reliable and efficient micropropagation protocol was developed for Stachys byzantina, a valuable and promising ornamental species. For the initial in vitro cultures on the Murashige and Skoog (MS) medium, shoot tips were used as explants. The addition of 5 μM of kinetin (KIN) resulted in the production of multiple (6.0 shoots/explant) and elongated (3.6 cm) shoots. The MS medium supplemented with 10 μM of a-Naphthaleneacetic acid (NAA) proved efficient for the in vitro rooting (73.3%) of the microshoots. For the ex vitro rooting of the microshoots, the treatment with 0.5 g L−1 of Indole-3-butyric acid potassium salt (K-IBA), before planting in 1:1 (v/v) peat and perlite substrate and placed in a fog system, led to 86.7% rooting. The acclimatization stage was successful, and 96.7% survival was recorded for the ex vitro-rooted plantlets. Inter Simple Sequence Repeat (ISSR) markers were employed to examine the genetic uniformity of the in vitro-derived plantlets with the mother S. byzantina plants. The monomorphic banding pattern in the micropropagated plants and the mother plant confirmed the genetic uniformity of the in vitro-derived plantlets and revealed the reliability of the proposed in vitro protocol for S. byzantina. As far as we know, this is the first study on a combined micropropagation and genetic uniformity assessment of the species, the findings of which could be further used to apply new in vitro cultivation techniques or to produce elite genotypes of S. byzantina.

Summary The dioecious gymnosperm self-sown ornamental plant Ephedra foeminea Forssk (Ephedraceae: Gnetales) has a special interest due to its nutraceutical and pharmaceutical properties. The present study contributes with data about the phenology of the plant in Attica, Greece, and the complex of its scale insect pests (Hemiptera: Coccomorpha), Stotzia ephedrae (Newstead) (Coccidae) (morphology, phenology, biology, natural enemies), Dynaspidiotus ephedrarum (Lindinger) (morphology, natural enemies) and Leucaspis riccae Targioni Tozzetti (Diaspididae) (natural enemies), based on observations made from April 2021 to June 2023. Stotzia ephedrae which was the scale species found in higher numbers on E. foeminea is a univoltine, oviparous and biparental species recorded as settled 1 st instar nymph on the shoots of E. foeminea from May to January. The fecundity of the scale fluctuated between 370 and 598 eggs per female. The results on the phenology of S. ephedrae contribute to the knowledge of the critical period for the pest control, i.e. from May to January during which the scale remains in the sensitive first instar. In addition, the records of parasitoids and predators in the colonies of the scale insects infesting E. foeminea provide information on the available natural enemies for potential use in biological control schemes of these pests.

Sword lily is regarded as a useful and commercially demanding cut flower crop; hence, assessing its responses to abiotic stress, particularly salt stress, is vital. Melatonin (MT) exhibits stress tolerance in crop plants and is an emerging stress relieving alternative to chemicals. Nevertheless, the possible process underlying the effects of MT under salt stress has yet to be fully elucidated in plants. Herein, the salt stress (SS) mitigation potential of MT was assessed in a commercially important cut flower, sword lily. Melatonin, expressed as MT1, MT2, MT3, and MT4, was administered at concentrations of 0.2, 0.4, 0.6, and 0.8 mM. The results revealed that SS (5 dS m-1) restricted the growth and physiological aspects of sword lily. Furthermore, malondialdehyde (MDA), hydrogen peroxide (H2O2), membrane permeability, endogenous proline, and soluble protein contents were enhanced in SS. MT application improved morphological traits, photosynthetic pigments, and corm traits. The application of MT mitigated the effects of SS stress in Gladiolus grandiflorus plants by improving growth and photosynthetic pigments. MT application under SS improved the reducing and non-reducing sugar and NPK contents of the sword lily. Furthermore, MT improved the levels of secondary metabolites, such as anthocyanins, flavonoids, and ascorbic acid, in sword lily. Moreover, MT supplementation ameliorated salt-induced oxidative stress in the gladiolus, as depicted by a decrease in stress markers (EL, MDA, and H2O2) and an increase in defense-related enzymes (POD, CAT, and SOD) with highest increase in the MT3 treatment under salinity stress. The SOD and CAT enzyme activities were 3-3.6-fold higher in the MT3 under stress than the control. In conclusion, MT applications on cut flowers can be an effective strategy to reduce salt stress and can be used to regulate salinity stress in cut flower production. MT can be used as a safe alternative to other agrochemicals to maintain the growth and flower quality of sword lilies, with beneficial effects during vase life.

Salt stress is a major abiotic aspect that inhibits plant development, growth, and productivity of ornamental plants. In recent years, there has been a lot of interest in seed priming and biological treatments for salt stress mitigation in plants. Melatonin (MLT) is a versatile signaling molecule detected in higher plants. Its function is involved in various signaling and physiological processes, particularly under severe environmental conditions. The aim of this study was to assess the performance of different levels of MLT (0, 1, 10, 20 mu M) primed zinnia plants (Zinnia elegans cv. 'Super Yoga') under salt stress (100 mM NaCl). Salt stress exposure reduced growth and physiological variables and increased oxidative stress, recorded as a rise in stress markers. The results showed that seed priming with MLT improved morphological characteristics of zinnia, such as shoot and root length, shoot diameter, leaf length, root collar diameter, number of roots, root fresh, and dry weight. MLT based seed priming also increased photosynthesis pigments and reduced salt induced oxidative damage by enhancing the activity of antioxidant enzymes (i.e. superoxide dismutase-SOD, peroxidase-POD, and catalase-CAT). The reduction in oxidative stress was recorded as decrease in electrolyte leakage (EL), hydrogen peroxide (H2O2), and malondialdehyde (MDA). Primed plants also showed significant increase in the osmoprotectants proline and glycine betaine, as compared to the non-primed salt stress plants. Exposure of plants to salt stress lead to an increase in sodium (Na+) and potassium (K+) contents in plant tissues in the non-primed plants. However, priming with MLT reduced the uptake of Na+ and improved the uptake of K+ in the leaves of zinnia. Overall, these results provided evidence that MLT seed priming may ameliorate the ill effects of salt-induced oxidative stress in zinnia plants.

The longevity of cut flowers is associated with various physio-biochemical traits. To extend vase life (VL) of cut flowers, a wide range of chemical-based preservatives solutions have been used, which raise the concerns of human health and environmental pollution. This study explored the potential of using ascorbic acid (AsA) to naturally extend the VL of cut sword lily (Gladiolus grandifloras) ‘White Prosperity’ flowers. Fresh spikes were placed in vase solutions containing 1, 2, 3 and 4

Osteospermum ecklonis DC. NORL. is native to South Africa and is fully adapted to the Mediterranean climate. The aim of the study was to elucidate morphological and developmental changes in O. ecklonis plants associated with drought resistance in response to low doses of UV-C. Growth responses under three levels of drought stress (NW: normal watering, MD: moderate drought stress and SD: severe drought) were recorded. The results showed that 1 kJ m−2 UV-C significantly (p < 0.05) increased resistance to water stress without affecting growth and development or damaging photosystem II. Fresh weights of the upper parts and the root system of the irradiated plants were maintained at similar levels to those of the non-irradiated control plants. Fv/Fm values in the irradiated plants ranged from 0.73 to 0.82 depending on the stress level, while in the non-irradiated plants, the values ranged from 0.69 to 0.83. Differences between UV-C irradiated and non-irradiated plants were recorded in electrolyte leakage (EL), in malondialdehyde (MDA) and in relative water content (RWC) at all drought levels. The EL percentage of the non-irradiated plants at SD was 19.7%, while in the irradiated plants, it was 17.8%. RWC rates in the irradiated plants ranged between 60.6 and 76.4%, while in the non-irradiated plants, they ranged from 54.2 to 63.6%. Superoxide dismutase (SOD) and catalase (CAT) activities increased with UV-C irradiation, suggesting that antioxidant responses were induced and protected cell membranes from lipid peroxidation and damage. The results of the present study showed that UV-C irradiation at 1 kJ m−2 alleviated the drought symptoms of O. ecklonis by reducing oxidative stress and membrane lipid peroxidation.

Plant small molecules, such as nitric oxide (NO) and melatonin (MN) as natural and human health-friendly compounds, play important roles in the mitigation of abiotic stresses in plants. Heavy metals such as chromium (Cr) are hazardous for the survival of ornamentals, especially edible flowers. This study evaluated the effects of NO (50 µM; sourced as sodium nitroprusside) and MN (50 µM) applied two times through foliar spraying at 1-week intervals on alleviating Cr (120 µM; K2Cr2O7)-induced oxidative stress in edible flowers of Calendula officinalis cv. Orange King. Cr stress decreased plant dry mass, leaf SPAD values, net photosynthetic rates, and the maximum photochemical quantum yield (Fv/Fm), and increased the oxidative stress markers. The individual application of NO or MN significantly mitigated the adverse effects, and the combined application of NO and MN synergistically enhanced plant tolerance to Cr stress, including increased activities of antioxidant enzymes in plants and concentrations of carbohydrate, ascorbic acid, sugar, total protein, as well as ash contents of edible flowers. The co-application also significantly elevated the concentrations of total phenolics, flavonoids, free reducing power, antioxidant capacity DPPH, and total carotenoids in Cr-treated plants compared with those in Cr-stressed plants. Additionally, the essential oil contents in flowers increased in response to the signaling molecule treatment under Cr stress. Compared with individual applications, the co-application of NO and MN had more significant effects. Our results indicate that the combination of signaling molecules, such as MN and NO, can not only increase the biomass of edible calendula plants but also improve flower quality for use as a novel food.

Oil cakes are agro-industrial wastes produced in large quantities, with still untapped potential in plant production. Basil is one of the most economical essential oil crops cultivated worldwide, requiring sustainable production methods. This greenhouse experiments evaluated the effects of flaxseed oil cake (FOC) added to peat substrate at the rates of 5, 10, and 20 g dm(-3) on herbal yield, content of bioactive compounds and mineral elements, antioxidant activity, and essential oil composition of basil (Ocimum basilicum 'Dark Opal'), grown under well-watered and drought stressed conditions. Two-way ANOVA, principal components analysis (PCA), and correlation networks were applied to associate the data. PCA analysis indicated variability in basil responses to the different treatments, with each treatment forming distinct clusters. The study revealed the beneficial effect of FOC on basil herb yield under water stress. Applying 10 g dm(-3) FOC was the most effective in mitigating drought stress in basil. Under drought stress conditions, FOC at the rate of 10 g dm(-3) increased fresh weight by 63.9% and herb dry weight by 59.9% compared with the peat-only substrate plants. As FOC rates increased, the nitrogen level of plant tissues and substrates increased while reducing sugars, total polyphenols, and total flavonoids content decreased. GC-MS analysis of basil essential oil showed that the main compounds were tau-cadinol (10.79-12.54 %), linalool (4.93-10.01 %), methyl eugenol (4.11-6.71 %), alpha-bergamotene (3.11-5.48 %) and eugenol (2.10-5.05 %). Drought stress lowed the linalool, methyl eugenol and alpha-bergamotene concentrations compared with the well-watered plants. However, adding FOC increased the accumulation of linalool and methyl eugenol in all of the FOC treatments under drought stress. Analysis of the differential network showed that the fresh and dry weight and the methyl-eugenol content as "hub" parameters correlated with most traits of basil grown under well-watered and drought stress conditions. In conclusion, using FOC at appropriate levels can effectively reduce plant herb yield loss caused by water stress.

Quality of cut flowers is always associated to vase life at the consumer. In previous studies, novel preservative postharvest treatments have been tested to prolong vase life and commercial quality. The aim of this work was to study the potential use of borage (Borago officinalis L.) leaf extract as natural vase life enhancer for cut gladiolus flowers. Borage leaf extracts (BE) applied as 1 %, 2 %, 3 % and 4 % (v/v) in vase solutions extended the vase life from 6.2 to 13 d. We recorded a concentration of BE at 3 % significantly improved the number of open flowers, the floret diameter, the relative fresh weight, chlorophyll and carotenoid content. BE showed antioxidant properties, as they decreased oxidative stress and reduced the lipid peroxidation as demonstrated by the malondialdehyde (MDA), hydrogen peroxide (H2O2) concentrations and membrane stability index (MSI). Postharvest treatment with BE boosted proline content in cut gladiolus, indicating a reaction that was associated with the alleviation of water stress. BE application improved total soluble proteins, sugars and phenols in the florets resulting in prolong of the vase life. Bacterial count was reduced in BE treated vase solutions depicting less proliferation of bacteria at stem ends and hence reduced stem blockage. The best postharvest performance was obtained by the BE at 3 %. The promising results of current experiments, may be suggested as potential postharvest treatment to prolong the vase life of sword lily.

Gladiolus is a well-known bulbous plant producing impressive cut spikes. Hydrogen sulfide (H 2 S) and nitric oxide (NO) are vital signaling molecules required for the proper functioning of plant metabolism. Preharvest applications of these molecules to crops have gained attention in recent years due to their positive role in tackling abiotic stresses, although, their role in geophytes is comparatively less studied. We assessed the effects of preharvest H 2 S and NO treatments on development, flowering, harvest and postharvest performance of gladiolus inflorescences. NO and H 2 S + NO treatments increased preharvest performance of plants associated with corm production, inflorescences length and harvest time. Individual and combined treatments improved postharvest vase life (VL) up to 3.4 days. Total soluble proteins (TSP) were increased in response to H 2 S, NO and H 2 S + NO treatments by 39%, 43%, and 55%, respectively compared to the controls. Soluble sugars (SS) were increased after NO and H 2 S + NO treatments by up to 25% and 42%, respectively. Postharvest catalase (CAT) activity was higher by 65%, 68%, and 76% after H 2 S, NO and H 2 S + NO treatments, respectively. Malondialdehyde (MDA) was decreased by all preharvest treatments by up to 88%, although, only the combined H 2 S + NO treatment reduced H 2 O 2 and superoxide dismutase (SOD) activity. The results confirm that preharvest treatments with H 2 S, NO and H 2 S + NO may positively affect growth, floral traits and postharvest performance of cut gladiolus inflorescences.

Summary The scale insect Lineaspis striata (Newstead) (Hemiptera: Coccomorpha: Diaspididae) was recorded for the first time infesting a species of the family Pinaceae. Heavily infested ornamental shrubs of Picea glauca “Conica” by pre-ovipostiting and oviposting female adults of L. striata, were found in March 2018 and by a minor population consisting of pre-ovipositing female adults in February 2021, in Attica, Greece. The scale was settled on the base of the needles of the host plant.

Summary The scale insect Stotzia ephedrae (Newstead) (Hemiptera: Coccomorpha: Coccidae) was recorded for the first time in Greece οn 20 April 2021. It was found on Ephedra foeminea Forssk. (Ephedraceae: Gnetales) in Athens. From preliminary studies it was found that S. ephedrae is an oviparous, bi-parental species completing one generation per year.

Salt stress is a major abiotic stress factor that is increasing at a continuos pace and pressurizing global food security in view of climate change. Therefore, plant scientists are developing strategies to ameliorate the negative effects of salt stress on crop production. Melatonin (N-acetyl-5-methoxytryptamine; MT) is a vital bio-logical hormone in plants that modulates growth, development, and tolerance to extreme environmental conditions. Its exogenous application is used to improve resistance to various stressors. Gerbera (Gerbera jamosonii L. cv. Yunnanhong) is a vital ornamental flower crop moderately sensitive against salt stress. A series of experiments were conducted on gerbera plants grown under NaCl stress (150 mM) with or in the absence of MT at 0.1 and 0.2 mM. It was shown that salt stress reduced growth and physiological traits but also caused oxidative stress, as recorded by the induction of oxidative stress markers in cell tissues. Foliar application of MT, especially at the concentration of 0.2 mM, boosted plant growth, biomass production, photosynthetic pigments, and ameliorated oxidative stress. The decrease in oxidative stress was associated with improved antioxidant activity linked to the production of the enzymes catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD). Exogenous MT also improved potassium (K') uptake and restricted sodium (Na') uptake in the leaves of gerbera. In conclusion, optimal MT application may serve as a potential ameliorator of salt-induced oxidative stress and help in the regulation of salinity for gerbera production under the threat of climate change.& COPY; 2023 SAAB. Published by Elsevier B.V. All rights reserved.

Arsenic (As) stress hampers the growth and quality of ornamental crops especially cut flowers. However, studies related to the As stress tolerance in ornamental geophytes are scarce in literature. Furthermore, while the individual potential of melatonin (MLT) and salicylic acid (SA) for improving tolerance to metalloid toxicity is well recognised, their combined approach has yet to be investigated, particularly in ornamental cut flowers. This study showed that melatonin and/or salicylic acid improved Gladiolus grandiflorus (cv. Purple Flora) plant tolerance to As toxicity. Arsenic stressed plants had stunted growth, decreased chlorophyll contents, enhanced oxidative stress markers including hydrogen peroxide (H2O2), electrolyte leakage (EL), and malondialdehyde (MDA). Combined application of these protectants had a more pronounced impact in ameliorating the As induced oxidative stress in plants than those of individual application. The findings provide compelling evidence that using MLT in conjunction with SA improves resistance to As toxicity by increasing the activity of enzymatic antioxidants, protein and proline content.

Deltamethrin and imidacloprid are commonly used insecticides for controlling sub-sucking insects in greenhouses. However, their application may cause sublethal effects on the aphid coccinellid predator Coccinella septempunctata (Coleoptera: Coccinellidae). Here, we study (i) the toxicity and the effect of two sublethal doses (LD10 and LD30) of deltamethrin and imidacloprid on C. septempunctata in a laboratory microcosm and (ii) the residual toxicity of the two insecticides in a greenhouse. The results showed that both insecticides reduced fecundity, longevity, the intrinsic rate of increase, the finite rate of increase and the net reproductive rate. However, the developmental time of the fourth instar larvae was prolonged by both insecticides at LD10 and LD30. Deltamethrin residues were toxic 21 DAT (days after treatment) to C. septempunctata fourth instar larvae. In contrast, imidacloprid began in the slightly harmful category (75%) 1 DAT and declined to the harmless category (18.33%) 21 DAT. These results indicate that deltamethrin and imidacloprid have potential risks to C. septempunctata. This study provides information to guide the development of integrated pest management (IPM) strategies in greenhouses.