Empress Tree Research Articles

Impact of Foliar Conditioner on Translocation and Bioaccumulation of Trace Elements in Paulownia (Paulownia Siebold & Zuccarini, 1835)

The main objective of this engineering study was to investigate the impact of foliar conditioners on the translocation and bioaccumulation of trace elements in Paulownia trees. Paulownia, commonly known as the "empress tree," serves as a promising research subject within the environmental engineering context. The study focused on analyzing the effects of foliar conditioners on trace elements in this species, taking into account ecological and economic aspects. The obtained results aim to contribute to the development of effective strategies supporting the healthy growth of plants, addressing environmental protection concerns, and offering practical applications in Paulownia plantation management

RESEARCH ON SEED GERMINATION STIMULATION AT PAULOWNIA TOMENTOSA THUNB. STEUD.

Paulownia tomentosa (Thunb.) Sieb. & Zucc. Ex Steud. (syn. P. Imperialis Sieb. & Zucc.), is a native species to China, popularly being called “Princess Tree”. In Romania, the species is sensitive to the early frosts, which cause frostbite of non-lignified stems. Unprotected trees can be destroyed to ground level, but recover vigorously from shoots. Paulownia tomentosa is an invasive species introduced to the US from China as an ornamental and landscape tree in the mid-1800s. The family name derives from its genus Paulownia Siebold & Zucc., 1835 whose name was given in honour of the Danish princess Anna Paulowna or Pavlovna (1795-1865), the consort of King William II of the Netherlands and the daughter of Tsar Paul I of Russia (Gledhill, D., 2008). The aim of the research was to speed up the germination of Paulownia tomentosa seeds with Nitrozyme (based upon a highly concentrated and purified extract of marine kelp) in different concentrations: 0.1%, 0.3%, 0.5%, 0.7%, 0.9%. The germination capacity of the seeds decreases from the moment of dispersal even in optimal conditions of storage in the laboratory. In the case of treated seeds with 0.1% Nitrozyme the values of height and diameter of the seedling increased slightly.

The response of the invasive princess tree (Paulownia tomentosa) to wildland fire and other disturbances in an Appalachian hardwood forest

This study examined the response of princess tree (Paulownia tomentosa) to different disturbances and its potential to spread throughout its current range in the U.S. The study was established in Shawnee State Forest in southern Ohio, USA, which has historically experienced disturbances from mining, logging, ice storms and wildfire. Plots were established for vegetation sampling where fire had occurred with and without princess tree present, and where no fire had occurred with and without princess tree present. To determine the influence of disturbance types on the density of princess tree, redundancy analysis (RDA) was used. High stem density of princess tree seedlings occurred in areas that experienced high fire intensities and herbicide treatment. Seedlings on southwest slopes increased in abundance as the time from the last logging activity increases. Princess tree saplings were present in greater densities in areas that experienced medium fire intensities and the highest ice storm damage. Sapling density is greatest as ground cover and vegetation height increases and slope decreases. Princess trees reach maximum stem density on northeast slopes in areas not impacted by the 2009 fire. All disturbances considered, including wildfire, have created conditions conducive to princess tree growth and expansion into forest areas.

Laboratory Assessment of Host Plant Selection of the Brown Marmorated Stink Bug (<i>Halyomorpha halys</i>)

The behavioral response of brown marmorated stink bug, <i>Halyomorpha halys</i> (Hemiptera: Pentatomidae), to various phenological growth stages (leaf, flower and pod/seed/kernel) of six host plants (soybean, corn, sunflower, Early Scarlet and Mississippi Silver cowpeas, and princess tree leaf) was investigated in a Dual Choice Arena Test (DCAT) and Multiple Choice Arena Test (MCAT). In DCAT, each experiment consisted of one of the growth stages of each plant with princess tree leaf as the standard. In MCAT, two experiments were conducted using: (1) similar growth stages from the different plants and (2) different growth stages from the same plant. <i>Halyomorpha halys</i> distribution was observed at time intervals up to 24 hours after insects were released. Results from MCAT and Preference Index (PI) from the DCAT indicated that more <i>H. halys</i> were recorded on princess tree leaves. Mississippi Silver (PI=1.59±0.05) and Early Scarlet (PI=1.49±0.08) flowers were preferred over princess tree leaves and other flowers (PI≤1). Sunflower seed was the least preferred (PI=0.43±0.18) among similar growth stages. Overall, the reproductive stages were preferred over the vegetative stage. Our findings can be useful in developing management programs such as trap cropping for this pest.

Effect of Nitric Oxide on Seed Germination and Dormancy in Empress Trees

Freshly harvested empress tree (Paulownia elongata) seeds have physiologic dormancy. The aim of this study was to investigate the effects of exogenous and endogenous nitric oxide (NO) on the dormancy and germination of empress tree seeds. After treatment with different concentrations of sodium nitroprusside (an NO-releasing compound) solution, the germination percentage of seeds under 12 h of continuous light was significantly greater. Seed germination percentage was promoted significantly by 10–4 M sodium nitroprusside plus cold stratification compared with seeds treated with cold stratification only. At different hours during imbibition, empress tree seeds treated with 2-(4-carboxyphenyl)-4, 4, 5, 5- tetramethylimidazoline -1-oxyl-3-oxide potassium salt (c-PTIO), NG-nitro-L-arginine methyl ester (L-NAME), and sodium tungstate showed reduced seed germination percentages. During the early hours of imbibition, c-PTIO or sodium tungstate treatment inhibited seed germination significantly. The results showed that both exogenous and endogenous NO can release empress tree seed dormancy. Endogenous NO oxide was involved in dormancy release and germination of seeds during the early stages of imbibition. Wider application of NO may be used for breaking seed dormancy in other species.

Ґрунтова схожість насіння павловнії повстистої Paulownia Tomentosa (Thunb.) Steud. різного географічного походження

Досліджено ґрунтову схожість насіння павловнії повстистої, заготовленого у трьох регіонах України: Одеській, Закарпатській та Львівській областях. Встановлено, що насіння павловнії повстистої характеризується високою ґрунтовою схожістю незалежно від географічного походження материнських дерев в умовах України. Найвища ґрунтова схожість притаманна насінню походженням зі Львова. Оцінено вплив температурних умов на ґрунтову схожість насіння за двох змінних температурних режимів пророщування: +15 °С вночі і +20 °С вдень та +21 °С вночі і +25 °С вдень. Встановлено, що температура пророщування істотно впливає на ґрунтову схожість насіння. За температурного режиму пророщування +21…25 °С показники ґрунтової схожості значно вищі. Досліджено вплив стимуляторів схожості: попереднє намочування насіння у воді та розчинах стимовіту, корневіну, бурштинової кислоти, епіну, радіфарму на ґрунтову схожість насіння павловнії повстистої. Встановлено, що попереднє намочування насіння має найвищу стимуляційну дію на подальше проростання насіння в ґрунті серед досліджених стимуляторів схожості. Попереднє оброблення насіння препаратами стимовіт, корневін, бурштинова кислота, епін, радіфарм загалом дало позитивний ефект, підвищивши ґрунтову схожість насіння. Наведено дані з поширення плантацій представників роду Paulownia у країнах Європи.

Antibacterial potential of the phenolics extracted from the Paulownia tomentosa L. leaves as studied with use of high-performance thin-layer chromatography combined with direct bioautography

Paulownia tomentosa (Thunb.) Steud. is a medicinal plant with a very long established and considerable position in traditional Chinese medicine (TCM) and in those of the other Far East Asian countries (mainly in Vietnam, Laos, Japan, and Korea). In Europe, Americas and Australia, P. tomentosa is known as princess tree, empress tree, or foxglove tree, and it is cultivated as a beautifully blossoming ornamental tree. In TCM, all parts of P. tomentosa (i.e., timber, bark, leaves, flowers and fruits) are used for curative purposes. From a literature survey, a conclusion can be drawn that in phytochemical and ethnopharmaceutical studies relatively less attention has been paid to investigating the chemical composition and biological activity of the leaves than that of the other parts of this medicinal plant and for this reason, our research was focused on antibacterial properties of the phenolics extracted from the P. tomentosa leaves. There are two important novelties of our approach. One novelty is that the phenolics extract from the P. tomentosa leaves was fractionated into six fractions (I–VI, expectedly containing flavonoid aglycons, free phenolic acids, non-polar flavonoid glycosides, polar flavonoid glycosides and phenolic acids liberated by the acidic and basic hydrolysis, respectively). The other novelty is that antibacterial assay was performed for each isolated fraction with the use of high-performance thin-layer chromatography combined with direct bioautography (HPTLC-DB). The best separations were obtained for fractions I and II, somewhat worse separations were obtained for fractions III–V, and the lack of characteristic bands was observed with fraction VI. In the antibacterial assay performed upon the HPTLC fingerprints, the Gram positive Bacillus subtilis and the Gram negative Aliivibrio fischeri bacteria were used. Well pronounced antibacterial activity was established with the selected fingerprint zones derived from fractions I–IV, whereas a lack of antibacterial activity was observed with fractions V and VI. Identification of apigenin and p-coumaric acid in the chromatographic zones from fractions I and II was performed with use of HPTLC and HPLC-DAD-MS, aided by external standards. Fractions III and IV were found to have similar chromatographic patterns, which suggests the presence of semi-polar flavonoid sugar conjugates in the P. tomentosa leaves.

Post-wildfire recovery of an upland oak\u2212pine forest on the Cumberland Plateau, Kentucky, USA

BackgroundMany forests within the southern Appalachian region, USA, have experienced decades of fire exclusion, contributing to regeneration challenges for species such as oaks (Quercus spp. L.) and pines (Pinus spp. L.), and threatening the maintenance of oak-dominated forests in the future. While the use of prescribed fire as a forest management tool is increasing within this region, there remains a lack of information on the potential role of wildfire. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided an opportunity to investigate how wildfire affected forest vegetation response.ResultsWe examined the effects of fire severity, quantified using composite burn index (CBI), on basal area, stem density, and sapling recruitment for several key species. We also examined the effects of fire severity on understory species richness and illuminated the consequence of non-native species invasions following fire. Our results demonstrated a negative relationship between fire severity and basal area (stems ≥2 cm diameter at breast height; P ≤ 0.001), and a positive relationship with the recruitment of oak and pine saplings (both P ≤ 0.001), oak sapling density (P = 0.012), and non-woody understory species richness (P ≤ 0.001). We also found that increasing fire severity heightened likelihood of invasion by non-native species, specifically princess tree (Paulownia tomentosa [Thunb.] Siebold & Zucc. ex. Steud; P = 0.009) and Chinese silvergrass (Miscanthus sinensis Andersson; P = 0.028).ConclusionsWhere it is feasible, public land managers may be able to generate a range of fire severity during future prescribed fires that approximate some characters of wildfire. These fires, when implemented in southern Appalachian upland forests, may help recruit oaks and pines and boost their potential as future canopy dominants. However, the increased occurrence of non-native invasive species invasion following fire conveys the importance of targeted and timely eradication treatments before new populations of non-native species may become established or reproduce, contradicting the ecological benefits of fire.

Utilization of wood and bark of fast-growing hardwood species in energy production

In this research, the calorific value and ash content of wood and bark of some fast-growing hardwood species, such as tree-of-heaven, (Ailanthus altissima (Miller) Swingle), empress tree (Paulownia tomentosa (Thunberg) Steudel), trembling aspen (Populus tremuloides Michaux), oriental plane (Platanus orientalis Linnaeus) and black locust (Robinia pseudoacacia Linnaeus) were investigated in order to comprehend their behaviour during combustion and estimate their utilization potential as solid biofuels (pellets). Beech (Fagus sylvatica Linnaeus) wood was used for comparative reasons. Different ratios of all the studied species in mixture were examined in order to investigate the material ratio that provides a satisfactory calorific value, while parallelly meeting the ash content requirements of the pellet production standard (ISO 17225-2:2014). Black locust bark seems to greatly increase the calorific value of the material. Empress tree wood had the lowest ash content, meeting the requirements of the best class (ENplus A1 – residential use), while tree-of-heaven and poplar were classified into ENplus B class (third class of residential use). By using the appropriate proportions, all the materials examined could be utilized in pellet production.

Plant Community Effects and Genetic Diversity of Post-fire Princess Tree (Paulownia tomentosa) Invasions

Many naturalized populations of the invasive tree princess tree exist in North America, yet little research has quantified its effect on native plant communities. A series of recent wildfires in the Linville Gorge Wilderness Area (LGWA) promoted multiple large-scale princess tree invasions in this ecologically important area. To measure community shifts caused by these princess tree invasions across burn areas, we sampled vegetation in paired invaded and noninvaded plots in mature and immature invasions within two burn areas of the LGWA. Plant community composition shifted in response to princess tree invasion across all invasion stages and burn areas. Species richness and Shannon diversity values decreased in invaded plots. Overall community structure also differed in invaded plots within immature invasions (P=0.004). The distribution of princess tree age classes in both burn areas indicates that fire promotes invasion but is not necessary for subsequent recruitment. Additionally, preliminary genetic analyses among distinct princess tree populations revealed very low genetic diversity, suggesting that a single introduction may have occurred in the LGWA. This information regarding community shift and strong post-fire recruitment by princess tree may inform management decisions by prioritizing princess tree control immediately after wildfires and immediately before and after prescribed burns.

Laboratory rearing of the brown marmorated stink bug (Hemiptera: Pentatomidae) and the impact of single and combination of food substrates on development and survival

AbstractThe brown marmorated stink bug (BMSB),Halyomorpha halys(Stål) (Hemiptera: Pentatomidae) is non-native species that has rapidly expanded its range in the United States of America and Canada. This study was aimed at increasing our knowledge of the biology of BMSB and developing a rearing method. A laboratory culture maintained on 15 different foods (pear, peach, Granny Smith apple, red delicious apple, squash, tomato, carrot, green bean, grape, corn, leaves of princess tree, leaves of butterfly-bush, dry seeds of sunflower, cowpea, and peanut) had on average 26.0±2.1 eggs per egg mass, and an incubation period averaging 6.94±1.2 days. Developmental duration from second instar to adult averaged 28.2±0.9 days similar to second instars reared to adult on single diet of green beans, corn, sunflower, cowpea, and peanut seeds. Survival from egg to adult was 85.4% and a growth index (GI) of 2.2±0.2 for the laboratory culture comparable to ⩾2.0 GI and 80–90% reported nymphal development on a diet of dry sunflower, cowpea, and peanut seeds. We reared six generations of BMSB before the study was terminated. Our results indicate the foods that are better for BMSB growth, development, and survival.

Ornamental, crop, or invasive? The history of the Empress tree (Paulownia) in the USA

The Paulownia tree first arrived in the USA in the early nineteenth century and quickly transitioned from an exotic oddity to a beloved ornamental by some and a reviled invasive species by others. Many gardeners and horticulturalists praised the tree for its rapid growth and beautiful lavender blossoms. Critics thought the non-native tree a threat to native flora and sought its eradication. One species, Paulowniatomentosa, is invasive and has been especially vilified by organizations ranging from the National Park Service and National Forests Service to the US Department of Agriculture. Another species, Paulowniaelongata, started to gain attention as a viable domestic tree crop in the 1980s. Demand derived primarily from Asian countries, especially Japan where the tree had been traditionally used for dowry chests, furniture, and musical instruments. Due to over harvesting, Japan had suffered a severe shortage to the extent that Paulownia made up a large chunk of the country's wood imports. P. elongata and various hybrids are currently grown by Americans ranging from diversified farmers to businessmen and even former president Jimmy Carter. Paulownia growers believe that the tree's value expands beyond furniture and other carvings to environmental possibilities such as biofuels, biomass, electricity, and even air purification. Deemed a pest by some and a profitable commodity by others, the Paulownia has become a permanent part of the American landscape but measures must be taken to contain P.tomentosa and keep P.elongata from becoming invasive.

Removal of a hazardous azo dye (Basic Red 46) from aqueous solution by princess tree leaf

Batch biosorption experiments were carried out for the removal of Basic Red 46 (BR 46) from aqueous solution by using princess tree leaf (PTL) as a potential biosorbent. The effects of solution pH, biosorbent dosage and size, dye concentration, temperature and contact time on the biosorption of BR 46 onto the PTL were investigated. The experimental results showed that maximum pH for efficient BR 46 biosorption was about 8.0. The equilibrium was attained in 70 min. The amount of BR 46 sorbed onto the PTL increased with the increase of dye concentration, in contrary, it decreased with increases of temperature, biosorbent dosage and size. The equilibrium sorption was best described by the Langmuir isotherm model. The maximum monolayer sorption capacity was found as 43.10 mg g − 1 at 25 °C. Kinetic studies indicated that the pseudo-second order model fitted to the experimental data well. Thermodynamic parameters demonstrated that the biosorption process was spontaneous and exothermic. The results revealed that the PTL could be used as a low-cost alternative biosorbent for the dye removal from wastewater.

Interaction of fire‐related cues in seed germination of the potentially invasive species Paulownia tomentosa Steud

AbstractThe Empress tree (Paulownia tomentosa Steud.) is a fast growing deciduous tree originating from East Asia. It is grown as an ornamental plant, but can also be used as industrial wood. However, in some parts of North America, this species is considered invasive, with high impact on autochthonous populations. We have investigated whether post‐fire expansion of this species can be explained at the germination level by analyzing the interaction between physical (light and temperature) and chemical (smoke and nitrogenous compounds) fire‐related cues in the regulation of P. tomentosa germination. Light is the key environmental signal in the induction of germination of positively photoblastic P. tomentosa seeds. Smoke, applied in the form of extract (liquid smoke [LS]), stimulates light‐induced germination if applied during imbibition, or shortly after the inductive irradiation. This stimulatory effect of LS can be effectively prevented by far‐red light, suggesting that the mechanism of smoke action is phytochrome related. The LS had no effect on the germination percentage when applied during the phase of radicle protrusion. However, LS reduced radicle elongation and slowed its protrusion. The LS had no effect on the optimal temperature range of germination (23–27°C). The combined action of LS and KNO3 in light‐induced germination was more effective then when each chemical was applied separately. It can be concluded that all tested components of fire, except elevated temperature, operate to stimulate germination of P. tomentosa seeds, suggesting that the post‐fire invasive potential of this species can, at least in part, be explained at the germination level.

Predicting the post-fire establishment and persistence of an invasive tree species across a complex landscape

The reintroduction of pre-European fire regimes has allowed the entry of many invasive plant species into fire-dependant ecosystems of North America. However, the environmental factors that favor the post-fire establishment of these species across complex landscapes are not well understood and the initial establishment of invasive species does not necessarily result in long-term persistence. To evaluate the post-fire establishment and persistence of disturbance-dependent invasive plants, we studied the invasion of Paulownia tomentosa (princess tree, an early-successional species introduced from Asia) across three burns in the southern Appalachian Mountains. Based upon classification tree analysis, the presence/absence of P. tomentosa 2 years after burning was most strongly related to the cover of residual vegetation, topographic shading, and moisture availability. Spatial application of classification tree models to repeated survey data showed that P. tomentosa established across a wide range of microsites 2 years after burning. However, predicted habitat for P. tomentosa decreased by 63% 4 years after fire and by 73% 6 years after fire. Following its initial widespread establishment, P. tomentosa only persisted on xeric and exposed topographic positions that experienced high intensity burning. However, the sites where it persisted include rare community types that contain two endangered plant species that depend upon fire for successful reproduction. The control of P. tomentosa on these ecologically important sites may require special attention from land managers.

Population Variation of the Fall Armyworm,Spodoptera frugiperda,in the Western Hemisphere

Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), the fall armyworm is the most economically important maize pest in the western hemisphere. This research focused on the genetic variability of the maize host strain because there is a lack of information in this area of S. frugiperda research. Amplified fragment length polymorphism (AFLP) was used to assess the genetic variability of S. frugiperda over a large geographic area. Twenty populations were collected from the maize, one population was collected from princess tree, one population was collected from lemon tree, and one population was collected from bermudagrass. The 23 populations were from Mexico, the continental United States, Puerto Rico, Brazil, and Argentina. The objective of this research was to evaluate whether the majority of genetic variability was within populations or between populations. The AFLP results showed that the majority of the genetic variability is within populations and not between populations, indicating minor gene flow and suggesting that S. frugiperda in the Western Hemisphere are an interbreeding population.

Stimulation of Empress Tree Seed Germination by Liquid Smoke

The germination of Empress tree (Paulownia tomentosa Steud.) seeds is phytochrome-controlled. Liquid smoke could not induce germination in darkness but red light irradiation of liquid smoke imbibed seeds induced a high percentage of germination. Maximum germination was achieved at liquid smoke concentration of 0.1% (v/v) when present during the imbibition phase or during the phase of phytochrome activity. The light requirement of these seeds could be completely substituted by exogenously applied gibberellins. In the presence of liquid smoke, optimal concentrations of GA3, GA4, and GA9 necessary for inducing germination were several times lower than in the controls, while that of GA7 was equally active when applied at a concentration one order of magnitude lower. The inhibitory effect of the applied growth retardants was strongly reduced and liquid smoke, in the presence of retardants, allowed light-induced germination, if applied simultaneously or after retardants treatment.

Paulownia Tree Trials in Eastern Kansas

Paulownia [Paulownia tomentosa (Thunb.)], one of the fastest growing trees (Larson, 1981), has been grown in the southern United States for commercial production. Other names include princess tree, royal paulownia, and empress tree. It is a member of the Bignonia family and has enormous sized leaves (Johnson, 1973; Carpenter and Graves, 1981). This species was introduced into the USA in the early 1830's and has escaped cultivation in many areas and now proliferates throughout much of the southeast. It originally came from mainland China and is grown extensively in Japan, which is now the largest consumer of this commercial wood species. It is a short grown (rotation) species that is harvested at about 12 years. The United States exports large amounts of paulownia wood to Japan where it has been used for centuries primarily for furniture, which accounts for 75% of all imported logs. Wooden chests of drawers termed Tansu are made from this wood and nearly every Japanese home would have a Tansu of solid paulownia (Larson, 1981). It is a light wood, and chemical and physical properties indicate that it is not desirable for pulping, but good only for specialty wood products (Lee, 1981; Olson and Carpenter, 1985). Trees grow exceedingly fast on a variety of sites including hard, relatively infertile soils (Beckjord and McIntosh, 1983). Much has been written about nursery production and plantation culture of this species in the southeastern eastern United States (Stringer, 1986; Beckjord, 1982), but its potential in other areas has not been studied. This report presents a summary of our efforts to evaluate the suitability of establishing paulownia at four locations and its limit of latitude in the eastern part of Kansas.

Susceptibility of Paulownia elongata to Agrobacterium and production of transgenic calli and hairy roots by in vitro inoculation

Susceptibility of Paulownia elongata S.Y. Hu (princess tree) to Agrobacterium tumefaciens and A. rhizogenes was demonstrated by inoculating in vitro shoots. Shoots had a gall formation frequency of ≥83% when inoculated with any of three A. tumefaciens strains (542, A281, or C58). Timing of gall appearance and type of callus proliferation differed among A. tumefaciens strains. Rapidly proliferating callus was produced from explants that were inoculated with A. tumefaciens. Hairy roots were produced directly from wound sites on 33% of shoots inoculated with A. rhizogenes strain R1601. Rapidly growing detached roots were produced from explants that were inoculated with A. rhizogenes. Opine analyses demonstrated the expression of foreign genes in proliferating galls/hairy roots shortly after emergence from wound sites and in callus and roots after 12 weeks of in vitro culture. Southern analyses demonstrated the presence of tDNA in long-term callus and root cultures.

Effect of nitric oxide - releasing compounds on phytochrome - controlled germination of Empress tree seeds

Using different nitric oxide releasing compounds and appropriate controls we have obtained data strongly suggesting the involvement of nitric oxide in the phytochrome controlled germination of Paulownia tomentosa seeds. Direct detection of nitric oxide, under various experimental conditions, was performed by a spin-trapping technique combined with electron paramagnetic resonance (EPR) spectroscopy. The addition of methylene blue prevented light-induced and NO donors-potentiated germination of P. tomentosa seeds. This inhibition could be completely overcome by addition of gibberellin. The promotive effect of nitrite was pH dependent, maximally pronounced at the pH range where nitrite undergoes dismutation and liberates nitric oxide. Under these conditions, nitrite exerted its efficacy at the same concentrations at which nitric oxide releasing compounds such as sodium nitroprusside (SNP), S-nitroso acetylpenicillamine (SNAP), and 3-morpholinosydnonimine (SIN-1), were the most effective. Likewise, the potentiation of P. tomentosa seed germination could be achieved by chemical reduction of nitrite with Na2S2O4 during which liberation of nitric oxide could be detected.