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The paper studies the water regime of panicle hydrangea and 16 varieties of this species introduced into South-Ural Botanical Garden-Institute of the Ufa Federal Research Centre of Russian Academy of Sciences. The purpose of the work is a comparative assessment of hydrangea varieties resistance to drought and the identification of the most promising taxa suitable for cultivation in the Bashkir Cis-Urals. The study assesses the total moisture content, water retention capacity and the content of mobile moisture in hydrangea leaves for the growing season. It has been found that the total moisture content (water content in the tissues) of panicle hydrangea leaves and its varieties is quite high and ranges from 72 to 82%. Certain varieties (‘Bobo’, ‘Levana’, ‘Phantom’, ‘PrimWhite’, ‘Silver Dollar’, ‘Sandy Fraise’, ‘Unique’) have an ability to increase water retention during flowering. The following varieties are most adapted to dry periods under growing conditions in the forest-steppe zone of the Bashkir Urals: ‘Kyushu’, ‘Prim White’ and ‘Wim’s Red’, the least drought-resistant ones are ‘Tardiva’, ‘Sandy Fraise’ and ‘Praecox’; the other 10 varieties are classified as hydrangeas with medium drought resistance. H . paniculata has average values for all parameters of the water regime and their value does not depend on the phenophase.

The structure of the complex inflorescences of Hydrangea petiolaris Siebold et Zucc. and Hydrangea paniculata Sieb. was studied using physiognomic, structural, and fractal approaches. It is established that physiologically different inflorescences have a general structure, pleiothyrse, and the same number of flowers. The structure of inflorescences is generally orderly and has a modular organization. Changes in the structure of inflorescences occur in parallel in all modules owing to a reduction or an underdevelopment of flowers in each of the modules.

Developing management practices that make more efficient use of irrigation is important for improving the sustainability of nursery crop production. Integrating refined irrigation scheduling with a substrate amendment like biochar can improve irrigation efficiency. The objective of this research was to evaluate the impact of biochar and need-based irrigation scheduling on gas exchange, plant water relations, and biomass gain of container-grown Hydrangea paniculata ‘Silver Dollar’ with the goal of reducing water use and maintaining or shortening production cycles. Containers were filled with pine bark and amended with either 10% or 25% by volume of hardwood biochar. Plants were automatically irrigated by one of the three irrigation schedules. The irrigation schedules were conventional irrigation, delivering 1.8 cm of water in one event each day, and two on-demand, need-based irrigation schedules. The first was based on the moisture characteristic curve for each of the three substrates developed via the evaporative method. The second was a plant physiology-based irrigation scheduling regime built on the relationship between photosynthesis and substrate moisture content. Scheduling irrigation using a plant physiology or substrate physical properties basis, in combination with biochar, reduced the water requirement for ‘Silver Dollar’ hydrangea without any negative effect on plant dry weight by maintaining sufficient plant water status and gas exchange even just prior to irrigation. Automated irrigation systems coupled with a plant physiology or substrate-based actuation and a water retentive substrate amendment have the potential to reduce nursery crops water use.

The effective fraction of coumarin glycosides from Hydrangea paniculata Sieb (HP) has been under development for the treatment of chronic kidney diseases for years. Skimmin and apiosylskimmin are the main coumarin glycosides of HP, and the major metabolites in rats are 7-hydroxycoumarin (7-HC) and 7-hydroxycoumarin glucuronide (7-HCG). In this study, a sensitive and reliable liquid chromatography-Orbitrap mass spectrometry (LC-Orbitrap MS) method was developed for the simultaneous determination of skimmin, apiosylskimmin, 7-HC and 7-HCG in rat plasma. The chromatographic separation was performed on a Zobax SB C18 column (2.1 × 100 mm, 3.5 μm) at a flow rate of 0.3 mL/min with a gradient mobile phase of water and acetonitrile containing 0.2% formic acid. Skimmin, apiosylskimmin, and 7-HCG were detected in targeted-selected-ion-monitoring mode at positive ions m/z of 325.0911, 457.1331 and 339.0703, respectively. 7-HC and internal standard were detected in parallel-reaction-monitoring mode at m/z 163.0387→119.0492 and 260.1641→116.1071 to overcame the carryover of 7-HC. Linearity was obtained for the analytes within the range of 20-2000 ng/mL for skimmin, 5-500 ng/mL for apiosylskimmin and 7-HC, and 100-10000 ng/mL for 7-HCG. Validation parameters were all in line with the criteria of international guidance. The method has been applied to the pharmacokinetic study of HP in rats.

One of the ways to reduce the water consumption by plants while maintaining their proper quality is to use substances that limit excessive transpiration. Three preparations at following concentrations: Moisturin (10%), Root-Zone (4.5%) and Vapor Gard (1%), were used in the experiment. Moisturin and Vapor Gard were applied in the form of a single spray, and Root-Zone as a single irrigation in mid July.The aim of the research was to assess the effect of several anti-transpirants on some biometric features of the ‘Tardiva’ panicled hydrangea depending on the frequency of irrigation. The following parameters were measured: area, perimeter, width and length of leaf blade, length and width of inflorescences, and the diameter of shoots. Treatment of H. paniculata cv. ‘Tardiva’ with Root-Zone and Moisturin anti-transpirants with a single irrigation every other day allows to reduce the water consumption and obtain shrubs of a quality comparable with plants irrigated twice a day. The use of Moisturin with a twice daily irrigation positively affected the length and width of inflorescences.

Water resources can be used more efficiently by including sustainable substrate components like coir that increase water-holding capacity. The first objective of this study was to evaluate the impact of coir amendment rate on plant available water and plant gas exchange, with the goal of optimizing substrate available water and determining the optimum coir amendment rate in a greenhouse environment. The second objective was to establish the optimum method of determining plant available water using either plant gas exchange parameters or substrate physical properties. Greenhouse experiments were conducted with Hydrangea paniculata &lsquo, Jane&rsquo, (Little Lime&reg, hardy hydrangea) potted with one of five different coir rates (0%, 10%, 25%, 40% and 65%) mixed with pine bark on a volume basis. Plant gas exchange parameters and substrate water content were measured daily over a range of increasingly drier substrate moisture contents. Actual photosynthetic rates increased with increasing coir amendment rate and were highest with 65% coir amendment. Amending pine bark with coir increased the water storage capacity, plant available water, and plant gas exchange parameters. Results suggest that 65% coir amendment rate was the optimum amendment rate among those tested in a greenhouse environment and plant photosynthetic rate was the better method of determining plant available water.

Magnolia stellata is a rare subcanopy tree species that grows in secondary forests in warm temperate zones. It is now endangered due to habitat degradation by vegetation succession. In an attempt to improve the habitat, a 30 m × 10 m plot (0.03 ha) was set up with all vegetation including M. stellata being clear-cut in January 2012. The number of sprouts increased for 1–2 years after clear-cutting and then gradually decreased or remained constant. Five years after clear-cutting, the numbers of individuals and stems, and the total basal area (BA), were 87.0, 165.5 and 3.2%, respectively, of the values before clear-cutting. BA was highest for Ilex pedunculosa, followed by M. stellata and Hydrangea paniculata. Some sprouted individuals of M. stellata produced flower buds in the second year after clear-cutting, and flowered and fruited in the spring and summer of the third year, respectively. The densities of potential canopy species were 18,533 ha−1 (height > 0.5 m) and 7,267 ha−1 (height > 1.2 m), vastly exceeding the value of the criterion for successful natural regeneration after clear-cutting of warm temperate forests in the region (3,000 ha−1). Based on this criterion, it is thus considered that the natural regeneration has reached completion. However, 45.1% (height > 0.5 m) and 95.5% (height > 1.2 m) of M. stellata individuals were regenerated by sprouting. Further research is needed into how individuals, regenerated from seedlings, develop and reach sexual maturity, and how successive generations change.

Nickel ferrite (NiFe2O4) spinel-structured nanoparticles (NPs) were synthesized by a green synthesis approach using Hydrangea paniculata flower extract. Green synthesis of NPs was preliminary monitored by a color change. Further confirmation was carried out using different techniques. X-ray diffraction analysis confirmed the cubic crystalline system (fcc) of NiFe2O4. Energy-dispersive spectrum analysis showed the presence of iron, nickel, oxygen, and carbon. Scanning electron microscopy revealed the agglomerating nature of the NPs (30–50 nm). The specific surface area was found to be 46.73 m2/g, revealing the average size D of NPs to be 24 nm. Transmission electron microscopy confirmed the spherical, oval, and irregular shapes of the NPs with a size range between 10 nm and 45 nm, and an average size of 28 nm. The magnetization of the obtained NiFe2O4 NPs in a high magnetic field of 20 kOe was found to be 20 emu/g. The values of remanent magnetization (Mr) and coercive field (Hc) were found to be 1.1 emu/g and 28 Oe, respectively. In the process of magnetization reversal (with a small value of Mr/Ms, 0.055), NiFe2O4 NPs had a loop with low energy loss, showing that the obtained NiFe2O4 NPs were soft magnetic materials. The magnetization curve with a sigmoidal shape indicated that the obtained NiFe2O4 NPs are super-paramagnetic material. In addition, the comparison of green synthesis with the methods available in the literature proved that the green synthesis is the best method. Thus, it is clear that green synthesis is a novel eco-friendly approach for the synthesis of magnetic NiFe2O4 NPs.

Further study on the constituents from the stems of Hydrangea paniculata Sieb resulted in isolation of two new compounds 1–2, including 1 monoterpenoid and 1 phenolic glycoside, along with 10 known compounds. Their structures were elucidated on the basis of spectroscopic data, including UV, IR, MS, and NMR experiments, along with chemical methods. At 10 μM, compounds 1 and 2 exhibited comparable activities with bicyclol in vitro assays for hepatoprotective activity against APAP-induced HepG2 cell damage.

Three new coumarin glycosides (1-3), together with three known compounds (4-6), have been obtained from the stems of Hydrangea paniculata Sieb. Their structures were elucidated based on spectroscopic data and chemical evidence. In addition, compounds 1-3 were screened for their neuroprotective effects against serum deprivation-induced PC12 cell damage, hepatoprotective activities against DL-galactosamine-induced toxicity in HL-7702 cells and their ability to inhibit LPS-induced nitric oxide production in the murine microglia BV2 cell line, but they were inactive.

Magnesium nanoparticles (MgNPs) and silver nanoparticles (AgNPs) were synthesized by green synthesis method using Hydrangea paniculata flower extract. The occurrence of various organic molecules like terpenoids, steroids, saponins, alkaloids, quinone, glycosides and flavonoids in the flower was revealed by phytochemical and gas chromatography–mass spectrometry analyses. The formation of brown and black colloids, confirmed the presence of MgNPs and AgNPs, which was further supported by ultraviolet-visible absorbance at 360 and 450 nm by MgNPs and AgNPs. The X-ray diffraction analysis confirmed the cubic phase of MgNPs and AgNPs. FTIR analysis showed the presence of functional groups on the biosynthesized nanoparticles surface. The SEM and TEM analyses demonstrated the formation of spherical and ellipsoidal MgNPs and AgNPs. MgNPs was about 56–107 nm in size, whereas AgNPs was approximately 36–75 nm. In addition, both MgNPs and AgNPs showed excellent antioxidant potential and antibacterial activity against Escherichia coli and Staphylococcus aureus . The current green synthesis method using H . paniculata flower extract is a simple and an eco-friendly approach to synthesize MgNPs and AgNPs for making beneficial health care products.

Managers of ornamental nurseries are increasingly reusing runoff water as an irrigation source, but residual pesticides in recycled water may result in plant phytotoxicity on crop plants. Our study focused on understanding the responses of container-grown landscape plants to residual pesticides in irrigation water. Hydrangea paniculata &lsquo, Limelight&rsquo, Cornus obliqua &lsquo, Powell garden&rsquo, and Hosta &lsquo, Gold standard&rsquo, were exposed to various concentrations of isoxaben, chlorpyrifos, and oxyfluorfen (0, 0.15, 0.35, 0.7, and 1.4 mg/L of isoxaben, 0, 0.05, 0.1, 0.2, and 0.4 mg/L of chlorpyrifos, and 0, 0.005, 0.01, 0.015, and 0.02 mg/L of oxyfluorfen) applied as overhead irrigation. After three months of application, we assessed the dry weight biomass, growth, and parameters related to photosynthetic physiology (SPAD chlorophyll index, light-adapted chlorophyll fluorescence, and photosynthesis carbon dioxide response (A/Ci) curves. We also sampled plant leaf, stem, and root tissues for residual pesticides. The effects of the pesticides were pesticide-specific and taxa-specific. Exposure to oxyfluorfen resulted in visible injury in all three taxa and reduced total biomass, chlorophyll index, and photosynthesis in Hydrangea and Hosta. All three taxa absorbed and retained pesticides in leaf and stem tissues. Growers should follow best management practices to reduce exposure from irrigation with runoff, particularly for herbicides with post-emergent activity.

Panicle hydrangea (Hydrangea paniculata) is a perennial ornamental plant belonging to the Saxifragaceae commonly used in gardens, characterized by massive upright flowers from midsummer to autumn. Starting from the end of August 2017, a previously unknown leaf spot was observed on 2- to 3-year-old plants of H. paniculata grown in borders in a garden located in Valle Cervo near Biella, northern Italy (45°36′00″N, 8°03′00″E). Ten out of 20 plants grown in this garden were affected, with 30 to 40% of leaves showing symptoms, consisting initially of circular necrotic spots, with diameter ranging between 20 and 80 mm, well defined by a brown margin. Severely infected leaves became chlorotic and abscised. The disease started from basal leaves on plants grown in shadow, at high relative humidity. In several isolations carried out from infected tissues on potato dextrose agar amended with 25 mg/liter of streptomycin sulfate a fungus was consistently isolated. After 15 days of incubation, black pycnidia, 127 to 255 μm diameter, developed, releasing hyaline, elliptical, nonseptate conidia, measuring 4.3 to 10.3 μm (average 6.9 μm) × 1.9 to 4.1 μm (average 2.7 μm). On the basis of its morphological characteristics, the fungus was identified as Phoma sp. (Boerema et al. 1976). The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 and sequenced. BLAST analysis of the 517 bp obtained showed 100% homology with Boeremia exigua (formerly Phoma exigua) (GenBank accession nos. MF039478, MF599109, and MF599108). The nucleotide sequence has been assigned the GenBank accession number MG766873. Because ITS analysis was not able to identify the varietas of this species, additional genes (elongation factor 1 alpha gene [EF1α] and β-tubulin [BTUB]) were amplified with primers EF1-728F/EF2 and Bt2a/Bt2b, respectively, and sequenced. BLAST analysis of the EF1α 449-bp sequence (GenBank accession no. MG970366) and the BTUB 372-bp sequence (GenBank accession no. MG970365) showed 100 and 99% similarity with the sequences of B. exigua var. exigua (GenBank accession nos. KY550228 and KR010463, respectively). Pathogenicity tests were performed by spraying leaves of healthy 24-month-old H. paniculata plants grown in pots at temperatures between 16 and 22°C with a spore and mycelial suspension (10⁶ CFU/ml). After artificial inoculation, leaves were covered with transparent plastic bags for 5 days. Plants sprayed only with sterile water served as a control. Three plants were used for each treatment. Lesions similar to those seen in naturally infected leaves developed on leaves 7 to 10 days after inoculation in all three inoculated plants, whereas control plants remained healthy. The same fungus was consistently reisolated from the lesions. The pathogenicity test was carried out twice. To our knowledge, this is the first report of B. exigua var. exigua on H. paniculata in Italy. The pathogen has been previously reported on H. macrophylla in Italy and the United States (Farr and Rossman 2017; Garibaldi et al. 2006). The disease is at present limited to a few gardens in the mountain region where it was observed.

Three new monoterpenes, hydrangines A-C (1-3), together with four known compounds, were isolated from the ethanol extract of the leaves of Hydrangea paniculata. The structures of new isolates were elucidated on the basis of extensive 1D and 2D NMR analyses, and their absolute configurations were determined by comparison of experimental and calculated electronic circular dichroism spectra. In in vitro bioassays at 10 μM, compounds 1-6 showed hepatoprotective activities against dl-galactosamine-induced toxicity in HL-7702 cells.

Clark, M. J. and Zheng, Y. 2015. Species-specific fertilization can benefit container nursery crop production. Can. J. Plant Sci. 95: 251–262. To determine the responses of six container-grown shrub species to different controlled-release fertilizer (CRF) application rates, plant growth and root-zone traits were evaluated following fertilization with Polyon®16–6–13, 5–6 month CRF incorporated at 0.60, 0.89, 1.19, 1.49 and 1.79 kg m−3N. The six species tested at a southwestern Ontario, Canada, nursery were Cornus stolonifera ‘Flaviramea’ (yellow-twig dogwood), Euonymus alatus ‘Compactus’ (dwarf winged euonymus), Hydrangea paniculata ‘Grandiflora’ (Pee Gee hydrangea), Physocarpus opulifolius ‘Nugget’ (Nugget ninebark), Spiraea japonica ‘Magic Carpet’ (Magic Carpet spirea), Weigela florida ‘Alexandra’ (Wine and Roses weigela). Different species responded differently to the CRF rates applied. For the majority of species at the final harvest, growth index, plant height, canopy area, leaf area and above-ground dry weight were greater in high vs. low CRF rates; however, different species had different optimal CRF application rates or ranges: 1.49 kg m−3N for Hydrangea and Spiraea, 1.19 kg m−3N for Weigela, 1.19 to 1.49 kg m−3N for Cornus and Physocarpus, and ≤0.60 kg m−3N for Euonymus. Based on these species-specific optimal fertilizer rates or ranges, growers can group plant species with similar fertilizer demands, thereby reducing fertilizer waste and maximizing plant production.

This study was conducted to assess the hyperaccumulation and phytoremediation potential of copper (Cu) and lead (Pb) in Hardy ‘Limelight’ Hydrangea (Hydrangea paniculata) and the common sunflower (Helianthus annuus). The study also investigated the capacity of these two plants to transpire the metals in a temperature-controlled greenhouse. Plants were grown for 4 weeks and periodically watered with known elemental concentrations of copper oxide nanoparticles, copper sulfate, and lead nitrate. Both H. annuus and H. paniculata accumulated significant amounts of Cu and Pb to be classified as hyperaccumulator species. H. annuus took up significant amounts of Cu in the shoots, specifically the leaves (Cu max. = 1368 ppm), and easily translocated it from stem to leaf (translocation factor (TF) ranged from 2.7 to 81.0). Pb was not as easily taken up and translocated (TF = 0.6) as Cu was by this species. H. paniculata took up Cu and Pb in high concentrations but preferentially stored more metals in the stems (Cu max. = 1757 ppm; Pb max. = 780 ppm) than in the leaves (Cu max. = 126 ppm; Pb max. = 35 ppm). The translocation ability of H. paniculata was much lower for both metals compared to H. annuus. Both Cu and Pb transpired from H. annuus at concentrations of 0.04 and 0.005 ppm, respectively.

Region-specific trials examining optimum controlled-release fertilizer (CRF) rates for the Canadian climate are limited. This study was conducted to determine an optimum range of CRF application rates and the effect of the application rate on growth, nitrogen (N), and phosphorus (P) losses of six economically important container-grown woody ornamental shrubs using typical production practices at a southwestern Ontario nursery. Salix purpurea ‘Nana’, Weigela florida ‘Alexandra’, Cornus sericea ‘Cardinal’, Hydrangea paniculata ‘Bombshell’, Hibiscus syriacus ‘Ardens’, and Spiraea japonica ‘Magic Carpet’ were potted in 1-gal pots and fertilized with Polyon® 16N-2.6P-10K (5–6 month longevity) incorporated at rates of 0.8, 1.2, 1.7, 2.1, and 2.5 kg·m−3 N in 2012. The experiment was repeated for the 2013 growing season with rates of CRF incorporated at 0.05, 0.35, 0.65, 0.95, and 1.25 kg·m−3 N. Plant performance (i.e., growth index) and leachate electrical conductivity (EC) and pH were evaluated once every 3 to 4 weeks during the respective growing seasons. The amount of N and P lost to the environment was determined for the 2012 growing season. The interaction between nutrient supply rate and target species affected most response variables. Although higher levels of fertilization produced larger plants and had the potential to decrease production time, increased losses of N and P and higher EC leachate values occurred. Results of this study indicate that an acceptable range of CRF application rates can be used for each species depending on the production goals, i.e., decreased production time, maximum growth, or decreased nutrient leachate. Overall, the highest acceptable CRF rates within the optimal range were: 1.25 kg·m−3 N for Spiraea; 1.7 kg·m−3 N for Hydrangea; 2.1 kg·m−3 N for Cornus; and 2.5 kg·m−3 N for Weigela, Salix, and Hibiscus. The lowest acceptable rates within the optimal range were: 0.35 kg·m−3 N for Hibiscus; 0.65 kg·m−3 N for Cornus, Weigela, Salix, and Spiraea; and 0.80 kg·m−3 N for Hydrangea.

Appropriate timing and rate of cold deacclimation is a critical component of winter-survival of temperate perennials. However, little is known about the physiological and biochemical changes involved in the deacclimation process. In this study differential expression of proteins in bark and xylem and changes in the quantity and biophysical nature of water in stems of Hydrangea paniculata during deacclimation were investigated. Increasing temperature caused a sigmoid deacclimation pattern in H. paniculata, which was characterized by a distinct decrease in the abundance of several stress- or defence-related proteins, most of which are known to be associated with increased freezing tolerance. In addition to quantitative reduction of stress- or defence-related proteins, proteins changing in abundance during deacclimation mainly fell into the functional categories of carbohydrate and energy metabolism, translation regulation and protein metabolism. Several tissue-specific responses in the accumulation patterns of proteins involved in stress, defence, carbohydrate metabolism or regulation/signalling and structural components were observed between bark and xylem. This indicates different stress responses in the two tissue types or is related to their different structure and functions. Deacclimation of bark was associated with rehydration and a decrease in the accumulation of dehydrins. The latter was correlated with changes in the least mobile stem water fraction, indicating that dehydrins may be involved in binding water in freezing tolerant cells. In xylem, no clear seasonal trend in the content and biophysical nature of water was observed and no dehydrins changing in abundance were identified. The results offer insight into tissue-specific responses during deacclimation of a moderately freezing tolerant woody perennial.

Irrigation practices for container nursery crops often result in over-application and can lead to leaching of nutrients and reduced growth. Our objectives were to: (1) compare growth and foliar nutrient content for plants under daily water use (DWU) based irrigation treatments, (2) determine DWU of 14 woody ornamental taxa, and (3) classify taxa into irrigation functional groups based on crop coefficients (KC). Irrigation was applied daily to 8 taxa in 2009 and 2010 using a control of 19 mm and three irrigation treatments: (1) replacing 100% plant DWU (100DWU) each day, (2) alternating 100% DWU with 75% DWU in a 2-day cycle (100-75DWU), and (3) a 3-day cycle replacing 100% DWU the first day and 75% DWU on the second and third days (100-75-75DWU). In 2009, seasonal average DWU ranged between 8.8 and 17.3 mm depending on taxa and treatment. Most DWU-based treatments resulted in less water applied than the control, yet plant growth was not reduced, and for one taxon (Hydrangea paniculata &lsquo, Limelight&rsquo, ) the 100DWU increased plant growth index. Lower foliar P and K concentrations were found for several taxa in control versus DWU treatments. In 2010, DWU for the season ranged between 2.1- and 22.0-mm d&minus, 1 depending on taxa and treatment. Growth was lower only for 100-75-75DWU Hydrangea paniculata &lsquo, compared to other treatments and there were no differences in foliar nutrient content.

In 2017, a new fungal species, Alternaria hydrangeae, was isolated from necrotic leaf spots of Hydrangea paniculata in Shenyang Botanical Garden, Liaoning, China. Phylogenetic analyses based on five genes (ITS, GPDH, Alt a1, RPB2 and TEF1) indicated that the species is a new taxon closely related to Alternaria deserticola in section Porri. Both species were significantly different from each other based on cultural features on SNA and PCA. Previously, A. deserticola was morphologically considered as A. acalyphicola. With respect to conidial characters, the species was distinct from A. acalyphicola in conidia shape, size and transverse septa. Pathogenicity tests indicated that it could induce necrotic symptoms on its host. The species is illustrated here as a new one causing leaf spot on H. paniculata.

The objective of these experiments was to evaluate the response of Little Lime™ hardy hydrangea (Hydrangea paniculata ‘Jane’) across two seasons in response to single foliar applications of three plant growth regulators (PGRs) at two rates: dikegulac sodium at 800 or 1600 ppm, benzyladenine at 300 or 600 ppm, or ethephon at 500 or 1000 ppm. There were two additional treatments: a hand-pruned control leaving three nodes and an unpruned water control (untreated) applied the same day as the PGR applications. To evaluate PGR efficacy, vegetative growth, floral attributes, branch symmetry, and phytotoxicity were assessed. Dikegulac sodium significantly increased branch number (BN) compared with all other treatments. Branch symmetry was greater in dikegulac sodium (800 or 1600 ppm) and hand-pruned treatments compared with the untreated and other PGR treatments (2011 and 2012). Flower number was greater in all PGR treatments compared with hand-pruned plants (2011 and 2012). The only treatment that promoted more symmetrical branching without reducing flower count was dikegulac sodium (800 or 1600 ppm). Phytotoxicity was observed in both seasons; however, no injury symptoms were evident 16 weeks after treatment (WAT), the termination of the experiment.

A new phenylpropanoid glycoside (1), and two new coumarin glycosides (2, 3), together with two known compounds (4, 5), have been isolated from the stems of Hydrangea paniculata Sieb. Their structures have been determined by spectroscopic and chemical methods. Furthermore, compound 1 (50 μM) exhibited significant hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in vitro assays.

The purpose of this study was to evaluate the potential of naturally occurring aldose reductase (AR) inhibitors from white-color natural products (Aruncus dioicus var. kamtschaticus, Chionanthus retusa, Cosmos bipinnatus, Hibiscus syriacus, Hydrangea paniculata, Magnolia denudata, Prunus padus, Robinia pseudo-accacia, Rhododendron mucronulatum for. albiflorum, Spiraea blumei, and Spiraea prunifolia var. simpliciflora). The MeOH extract of white-color natural products were tested on rat lens AR inhibition in vitro. Among them, the MeOH extract of R. mucronulatum for. albiflorum showed highest inhibition on AR (IC 50 value, 1.07 ㎍/ml). These results suggested that R. mucronulatum for. albiflorum, a white-color natural product, could be a useful resource in the development of a novel AR inhibitory agent against diabetic complications.

Suitability for production of woody floral stems in a pecan [Carya illinoinensis (Wangenh.) C. Koch] alley cropping was determined for nine shrub species in northwest Florida. Treatments included partial shade without root competition, partial shade with root competition, and full sun. Only three species had high rates of survival for all treatments throughout both years of the study: Callicarpa americana L. (American beautyberry), C. americana var. Lactea (white American beautyberry), and Crataegus marshallii Eggl. (parsley haw). For C. americana, plant growth index increased through time and was similar among the three treatments, indicating that this species grew equally well in sun or shade irrespective of root competition from the tree crop. C. americana var. Lactea had similarly high rates of survival and grew largest in partial shade without root competition (81.7 cm) compared to partial shade with root competition (67.2 cm) and full sun (57.0 cm). C. marshallii had 100 % survival in partial shade without root competition, with one mortality in partial shade with root competition (91.7 % survival) and one in full sun (91.7 % survival). Growth index did not increase over time and was similar among all three treatments. Other species tested had low rates of survival in all treatments throughout both years of the study and included: Ilex glabra L. (inkberry), Ilex myrtifolia Walt. (myrtle-leaf holly), Hydrangea paniculata Seibold var. ‘Tardiva’ (panicle hydrangea), Hydrangea quercifolia Bart. (oakleaf hydrangea), Lyonia lucida (Lam.) K. Koch, and Salix matsudana Koidz. F. tortuosa Rehd. (corkscrew willow). No species produced sufficient flowers, fruits or ornamental stems during this establishment period to allow a florist evaluation of the stems for use as woody floral stems.

Seed germination was optimized for ten Hydrangea macrophylla (Thunb.) Ser. and two Hydrangea paniculata Siebold cultivars in vitro. Methods were also developed to assay seed physiology. Best results for in vitro study were obtained with 0.5× Gamborgs solid media in conjunction with Plant Preservative Mixture (PPM), and by sterilizing seed with trichloro-s-triazinetrione (Trichlor). Assays of physiology were conducted by sterilizing seed and treating with combinations of white and red light, cold-treatment, gibberellic acid and potassium nitrate, and light cycles. Estimates of seed viability/dormancy, germination of non-dormant seed, and germination overall were calculated for each treatment combination. The most favorable conditions for overall Hydrangea seed germination were cold-treatment for 6 weeks, imbibition with GA3 + KNO3, and plating on half-strength Gamborgs media supplemented with GA3 in the presence of white light.

Landscape mulches are widely promoted to improve soil moisture retention, suppress weeds, and improve the growth of landscape plants. The objective of this project was to determine the effect of common landscape mulches (pine bark, hardwood fines, cypress mulch, color-enhanced ground pallets) on soil moisture, soil pH, weed control, and physiology and growth of landscape shrubs. Two additional treatments were not mulched: no mulch + no weed control and no mulch + weed control. Growth was measured on eight taxa (Euonymus alatus ‘Compactus’, Spiraea ×bumalda ‘Goldflame’, Weigela florida ‘Java red’, Taxus ×media ‘Runyan’, Thuja occidentalis ‘Golden Globe’, Hydrangea paniculata ‘Tardiva’, Viburnum dentatum ‘Synnestvedt’, Viburnum trilobum ‘Compactum’). Leaf gas exchange [net photosynthesis and stomatal conductance (g s)] were measured on Hydrangea paniculata, V. dentatum, and V. trilobum only. All mulches increased soil moisture compared with no mulch + weed control. There was no difference in soil pH or foliar nitrogen among treatments. All mulches, except cypress mulch, increased plant growth of most shrub taxa compared with no mulch without weed control. Mulches increased g S relative to no mulch without weed control. Photosynthetic rates of plants mulched with cypress mulch were less than the other mulches and not different from no mulch. Overall, the result suggests that, except for cypress mulch, the organic mulches tested are equally effective in improving growth of landscape plants. Reduced photosynthetic efficiency and growth of shrubs with cypress mulch suggest potential allelopathic effects.