Search Results (22)

The wide occurrence and expansive nature of invasive plant species are worldwide problems because these plants by their competitive character can lead to the loss of biodiversity. As a result, they significantly disrupt ecosystems, create economic damage and threats to human health, and diminish the quality of recreational resources. Therefore, sustainable, bio-based solutions are needed for their control, focusing on the utilization of their biomass after eradication. To better understand the potential application possibilities of invasive plants and their potential role in bioeconomy, species such as Lupinus polyphyllus—Lindl., Impatiens glandulifera Royle, Heracleum sosnowskyi Manden, Solidago canadensis L., Echinocystis lobata (Michx.), and Elodea canadensis Michx. were studied. These plants are not only widely spread but also form dense mono-stands and produce substantial amounts of biomass, which provides more options for their harvesting. In particular, their composition was analysed to assess the feasibility of their use for bioactive compound extraction. The amount of total polyphenols and flavonoids was determined in various parts of the studied invasive plants, and their corresponding radical scavenging activities were determined using DPPH, ABTS, FRAP and CUPRAC. The studied invasive plants are rich sources of polyphenols, and the highest concentrations were found in Impatiens glandulifera leaves, reaching a concentration of 7.78–11.75 g GAE/100 g DW, but in Lupinus polyphyllus, the highest concentrations of polyphenols were identified in the extracts of the flowers (12.77 g GAE/100 g DW) and leaves (11.88 g GAE/100 g DW) of the plant. Among the various plant parts studied, the leaves and flowers consistently showed the highest concentrations of polyphenols and flavonoids, as well as the greatest antioxidant and radical scavenging activities. These findings underscore the potential of invasive plant biomass as a source of valuable bioactive substances, particularly polyphenols, after the eradication of these invasive species. Full article

Globalization has greatly expanded the opportunities for plant species to enter new areas through a wide range of pathways. Elucidating the pathways of spread of alien species and the characteristics of organisms that make them invasive is one of the most pressing problems in ecological sciences. Once established, alien species may have serious implications for communities and vice versa. Allelopathy has been proposed as one of the possible invasion mechanisms of exotic plants. Impatiens parviflora and Impatiens glandulifera are among the widely spread invasive plant species in the Baltic region. The aim of the study was to evaluate the allelopathic effect of invasive Lithuanian Impatiens spp. and their neighboring plants (11 pristine species) using parameters of germination and seedling growth of biotest species Lepidium sativum, and to expand this study by determining the content of phenolic compounds and the radical scavenging activity in the leaf extracts of Lithuanian Impatiens spp. populations (20 of each Impatiens species). Leaf extracts of all species examined had an inhibitory effect on Lepidium sativum germination and morphology of the seedlings. In our study, at all leaf extract concentrations, significantly higher allelopathic potential on radicle growth was characteristic of I. glandulifera compared to native species Alnus glutinosa, Calystegia sepium, and Urtica dioica. At all leaf extract concentrations, I. parviflora showed significantly higher allelopathic potential on radicle growth compared to native species Urtica dioica. Impatiens glandulifera had a higher juglone index than Impatiens parviflora. I. glandulifera also had the highest juglone index compared to all neighboring species studied. The differences between the populations in the content of phenolic compounds, DPPH and ABTS radical scavenging activity were 2.3, 2.2 and 2.7 times for I. glandulifera and 2.6, 5.2 and 2.7 times for I. parviflora. The mean values of total phenolic content, DPPH and ABTS radical scavenging activity of I. glandulifera populations were 2.1, 2.7 and 3.3 times higher than those of I. parviflora populations, respectively. In general, our results about allelopathic potential and phenolics content, as well as free radical scavenging ability, confirm the supreme competitive ability of I. glandulifera compared to both I. parviflora and to the native co-occurring species. Full article

An HPLC-MS-DAD analysis of phenolic compounds was carried out on the extracts of staghorn sumac (Rhus typhina L.) and Himalayan balsam (Impatiens glandulifera Royle). This study focuses on the influence of solvent type and extraction time on the phenolic extraction efficiency from both invasive plants. Methanol extraction resulted in a 4.2 times higher content of hydroxybenzoic acids, a 3.7 times higher content of hydroxycinnamic acids, a 3.2 times higher content of flavanols, a 9.6 times higher content of flavanones, and an 8.7 times higher content of flavonols in the Himalayan balsam extract compared to aqueous extraction. Anthocyanins were only detected in the alcohol-based extraction. In comparison, the aqueous extraction from staghorn sumac resulted in a higher yield of total hydroxybenzoic acids, hydroxycinnamic acids, and flavonols, while the methanol extraction resulted in a 1.4-fold lower total polyphenolic content compared to the aqueous extraction. The type of solvent had no significant effect on the total content of flavanols in staghorn sumac. Extraction time considerably affected the total phenolic content in both plant extracts. After 84 h of extraction, the staghorn sumac extract showed a 3.5-fold increase in the total phenolic content compared to the initial measurement. In contrast, the Himalayan balsam extract showed a 40% decrease in the total phenolic content after 84 h. The Himalayan balsam extract reduced the germination of perennial ryegrass seeds by 55%, while the staghorn sumac extract reduced it by 80%. Both extracts also inhibited shoot and root growth of perennial ryegrass, although the Himalayan balsam extract at a concentration of 0.125 g/mL stimulated root growth of perennial ryegrass. The strategic use of invasive alien plants could be an effective approach to control their spread in the environment, potentially reducing management costs. The effectiveness of this approach depends largely on the type and content of allelochemicals present in the invasive plants. Full article

Invasive alien plants represent one of the five major threats to biodiversity and the disruption of ecosystems. They are introduced through various routes, starting with commercial trade. Preventing their introduction is essential to avoid the spread of new invasive plants. In this paper, we propose a new early warning DNA barcoding tool for invasive plant detection. Eight invasive alien species of European Union concern (i.e., Ludwigia grandiflora, Elodea nuttallii, Myriophyllum aquaticum, Pontederia crassipes, Ailanthus altissima, Heracleum mantegazzianum, Impatiens glandulifera, Pueraria montana) were selected and analysed. A unique DNA marker for each species was identified and amplified using species-specific primers capable of identifying the presence of alien species. To verify whether the approach could detect the presence of alien plants in urban areas from lawn clippings, mixes with typical urban spontaneous plants and invasive species were tested. In all mixes, only the invasive species was identified. This rapid detection capability will enable environmental operators to intervene promptly to contain the spread of invasive plants before they can cause significant damage to the local ecosystem. This tool could have a significant impact on the protection of local biodiversity and the integrity of urban habitats. Full article

The study of the semiochemicals produced by the flowers of Impatiens spp. is an important topic that may explain the reason for the rapid expansion of some species in this genus. Impatiens L. belongs to the Balsaminaceae family, which includes several species considered to be invasive plants in Europe. This study aimed to characterize the phytochemistry of four naturally occurring plant species in Poland, including three invasive alien taxa (Impatiens parviflora, I. glandulifera, and I. capensis) and one native species (I. noli-tangere). Gas chromatographic techniques were used to assess phytochemical profiles of chemical attractant cues in their pollination biology. We detected differences in the scent profiles of the investigated species. All the examined Impatiens species produce various alcohols, i.e., heptacosanol, octacosanol, aldehydes (e.g., octadecanal, eicosanal, etc.), and fatty acids, as well as long-chain hydrocarbons such as dodecane, tricosane, petacosane, hexacosane, and farnesene. Impatiens parviflora, I. glandulifera, and I. capensis produce geraniol and linalool, which attract members of the Apidae family, including bumblebees and honeybees. Impatiens parviflora also produces linalool-derived monoterpenes (linalool oxide and 8-hydroxylinalool), which are a strong attractant for Diptera; this may clarify why the species is mainly visited and pollinated by syrphid flies. A list of insect visitors to the Impatiens species under study can be found in the article. Full article

Two polyphenols–hyperoside (HYP) and protocatechuic acid (PCA) were reported to exert antidepressant activity in rodents after acute treatment. Our previous study also showed that this activity might have been influenced by the monoaminergic system and the upregulation of the brain-derived neurotropic factor (BDNF) level. A very long-term pharmacological therapy is required for the treatment of a patient with depression. The repetitive use of antidepressants is recognized to impact the brain structures responsible for regulating both emotional and cognitive behaviors. Thus, we investigated the antidepressant, anxiolytic, and procognitive effects of HYP and PCA in mice after acute and prolonged treatment (14 days). Both polyphenols induced an anxiogenic-like effect after acute treatment, whereas an anxiolytic effect occurred after repetitive administration. PCA and HYP showed procognitive effects when they were administered acutely and chronically, but it seems that their influence on long-term memory was stronger than on short-term memory. In addition, the preset study showed that the dose of 7.5 mg/kg of PCA and HYP was effective in counteracting the effects of co-administered scopolamine in the long-term memory impairment model induced by scopolamine. Our experiments revealed the compounds have no affinity for 5-HT_1A and 5-HT_2A receptors, whereas a significant increase in serum serotonin level after prolonged administration of PCA and HYP at a dose of 3.75 mg/kg was observed. Thus, it supports the involvement of the serotonergic system in the polyphenol mechanisms. These findings led us to hypothesize that the polyphenols isolated from Impatiens glandulifera can hold promise in treating mental disorders with cognitive dysfunction. Consequently, extended studies are necessary to delve into their pharmacological profile. Full article

River channels are regulated in various ways and the fertile soils of valleys are occupied for agricultural purposes, accompanied by human settlements. In many places on the floodplains, gravel or sand is mined and former pits fill with water. The consequences are changes in water relations, changes in land use and land cover. Natural riparian ecosystems gradually disappear. In addition, river valleys are susceptible places for the spread of invasive plant species. In the section of the Upper Odra Valley discussed in this article, all of the aforementioned factors have played roles in shaping modern habitats. The present study shows the impact of human-induced changes on the transformation of the plant cover of the Upper Odra Floodplain. In designated transects, we studied land use changes from 1910 to the present day and examined plant species diversity. The results show that the more heavily transformed floodplain adjacent to the channelized channel has a higher level of species diversity than agricultural areas located along a section of the river with a natural channel course. Most of the river valleys are colonized by geographically invasive alien species, such as Reynoutria japonica, Reynoutria sachalenesis and Impatiens glandulifera, which have contributed to the fact that all of the species typical of the ash, poplar and willow riparian forests characteristic of this habitat type have retreated, which is the main reason for the very low biodiversity. Full article

Impatiens glandulifera or Himalayan balsam is one of the most invasive weeds across Europe and can seriously reduce native plant diversity. It often forms continuous monocultures along river banks, but the mechanisms of this arrested succession are largely unknown. Here, we investigated the effect of arbuscular mycorrhizal (AM) fungi on balsam competitive ability with two native plant species, Plantago lanceolata and Holcus lanatus. We also studied how competition with Impatiens affects colonisation by foliar endophytes and mycorrhizas of two other co-occurring native species, Urtica dioica and Cirsium arvense. Mycorrhizal colonisation reduced balsam growth when the plants were grown singly, but appeared to have little effect when balsam experienced intra- or interspecific competition. Competition with balsam together with the addition of mycorrhizas had no effect on P. lanceolata biomass, suggesting that the fungi were beneficial to the latter, enabling it to compete effectively with balsam. However, this was not so with H. lanatus. Meanwhile, competition with Impatiens reduced endophyte numbers and mycorrhizal colonisation in U. dioica and C. arvense, leading to enhanced susceptibility of these plants to insect attack. Himalayan balsam is known to degrade soil fungal populations and can also reduce foliar beneficial fungi in neighbouring plants. This allows the plant to compete effectively with itself and other native species, thereby leading to the continuous monocultures. Full article

Biological invasions are a major component of global environmental change with severe ecological and economic consequences. Since eradicating biological invaders is costly and even futile in many cases, predicting the areas under risk to take preventive measures is crucial. Impatiens glandulifera is a very aggressive and prolific invasive species and has been expanding its invasive range all across the Northern hemisphere, primarily in Europe. Although it is currently spread in the east and west of North America (in Canada and USA), studies on its fate under climate change are quite limited compared to the vast literature in Europe. Hybrid models, which integrate multiple modeling approaches, are promising tools for making projections to identify the areas under invasion risk. We developed a hybrid and spatially explicit framework by utilizing MaxEnt, one of the most preferred species distribution modeling (SDM) methods, and we developed an agent-based model (ABM) with the statistical language R. We projected the I. glandulifera invasion in North America, for the 2020–2050 period, under the RCP 4.5 scenario. Our results showed a predominant northward progression of the invasive range alongside an aggressive expansion in both currently invaded areas and interior regions. Our projections will provide valuable insights for risk assessment before the potentially irreversible outcomes emerge, considering the severity of the current state of the invasion in Europe. Full article

The invasive plant species Impatiens glandulifera native to Asia mainly occupies European riparian ecosystems. It is still unclear to which extent this invasive plant can alter physico-chemical soil properties in terms of carbon turnover, microstructural stability and soil hydraulic properties threatening native plant species, here represented by Urtica dioica. Soil samples were collected from three sites in the Palatine forest near the river Queich, including bare soil (Control), or soil within dense stands of either I. glandulifera or U. dioica with similar texture. Basic soil parameters including SOM content and quality were analyzed. SOM is known to impact soil microstructural stability and soil hydraulic properties. We therefore assessed microstructural stability, the pore size distribution and the wettability. Our results implied more recalcitrant SOM for soil colonized by U. dioca including a lower pH. For soil colonized by I. glandulifera less recalcitrant SOM was detected indicating a reduced degradation which is likely given due to lignin as a predominant component in the plant biomass of I. glandulifera Soil microstructural stability was higher for soil colonized by the invader showing a slight increase with soil depth, due to higher SOM content. All in all, this case study indicates that I. glandulifera most likely affects the soil microbiome while basic soil parameters, soil hydraulic properties, wettability and soil microstructural stability showed no significant effect. Full article

Himalayan balsam (Impatiens glandulifera Royle) is an invasive garden ornamental plant species originating from Asia, which produces significant amounts of nectar. In Croatia, it is widely distributed along the banks of the Mura River. Although this plant species is widespread in Europe, there are still no available scientific data about this unifloral honey type. The results showed that Himalayan balsam honey is characterized by the high presence of pollen grains in the pollen spectrum (59–85%), natural higher diastase activity (39.1 ± 7.98 DN), negative specific rotation (−21.2° ± 6.89) and an extra light amber color (48.5 ± 12.69 mm Pfund). The carbohydrate profile is characterized by monosaccharides fructose (39.34 ± 0.65 g/100 g) and glucose (31.91 ± 1.42 g/100 g) with a ratio >1.23, while the most commonly represented disaccharide was maltose (3.04 ± 0.79 g/100 g). The average total phenolic content was 130.97 ± 11.17 mg gallic acid/kg honey, and the average antioxidant capacity value was 225.38 ± 29.58 µM Fe(II). The major mineral element was K, with an average of 533.92 ± 139.70 mg/kg. The sensory profile was characteristic with a light orange color and medium-intensity odor and aroma. The crystallization rate was moderate and characterized by the appearance of opalescence and gelatinous forms of crystals. The results of this study provide the first insight into the melissopalynological, physico-chemical and sensory profile of Himalayan balsam honey. Full article

An annual plant, Himalayan balsam (Impatiens glandulifera Royle) is globally widespread and one of Europe’s top invaders. We focused on two questions: does this species indeed not invade the southern areas and does the environment affect some of its key invisibility traits. In an isolated model mountainous valley, we jointly analyzed the soil (21 parameters), the life history traits of the invader (height, stem diameter, aboveground dw), and the resident vegetation (species composition and abundances, Ellenberg indicator values), and supplemented it with local knowledge (semi-structured interviews). Uncontrolled discharge of fecal wastewaters directly into the local dense hydrological network fostered mass infestation of an atypical habitat. The phenotypic plasticity of the measured invasion-related traits was very high in the surveyed early invasion (30–50% invader cover) stages. Different microhabitat conditions consistently correlated with its growth performance. The largest individuals were restricted to the deforested riparian habitats, with extreme soil nutrient enrichment (primarily by P and K) and low-competitive, species-poor resident vegetation. We showed that ecological context can modify invasion-related traits and what could affect a further invasion process. Finally, this species is likely underreported in the wider region; public attitude and loss of traditional ecological knowledge are further management risks. Full article

Biological invasions are renowned for their negative ecological and economic implications, however from studying invasions invaluable insights can be gained in the fields of ecology and evolution- potentially contributing towards conservation plans to deal, not only with biological invasion, but with other concerning issues, such as climate change. Impatiens glandulifera, or Himalayan balsam, is widely considered to be a highly problematic invasive, having spread across more than thirty countries during the past century. This paper will examine the findings which have arose from studying I. glandulifera and its impacts on the invaded ecosystem. Full article

Drought and higher temperatures caused by climate change are common stress conditions affecting plant growth and development. The reproductive phase is particularly sensitive to stress, but plants also need to allocate their limited resources to produce floral traits and resources to attract pollinators. We investigated the physiological and floral consequences of abiotic stress during the flowering period of Impatiens glandulifera, a bee-pollinated species. Plants were exposed to three temperatures (21, 24, 27 °C) and two watering regimes (well-watered, water stress) for 3 weeks. Not all parameters measured responded in the same manner to drought and/or heat stress. Drought stress induced leaf senescence, decreasing leaf number by 15–30% depending on growth temperature. Drought also reduced photosynthetic output, while temperature rise affected stomatal conductance. The number of flowers produced dropped 40–90% in response to drought stress, while higher temperatures shortened flower life span. Both stresses affected floral traits, but flower resources diminished in response to higher temperatures, with lower nectar volume and pollen protein content. We conclude that increased temperatures and drought stress, which are becoming more frequent with climate change, can negatively affect flowering, even if plants deploy physiological resistance strategies. Full article

The rapid spread of invasive plant species (IPS) over several decades has led to numerous impacts on biodiversity, landscapes, and human activities. Early detection and knowledge on their spatiotemporal distribution is crucial to better understand invasion patterns and conduct appropriate activities for landscape management. Therefore, remote sensing has great potential for detecting and mapping the spatial spread of IPS. This study presents a mapping of IPS (Reynoutria japonica and Impatiens glandulifera) over the last decade on two sites located in the central Pyrenees in the southwest of France, created using very high-resolution RGB aerial photographs. A supervised classification based on the random forest algorithm was performed using pixel attributes. The original spectral bands (RGB) were used, to which vegetation indices and textures were added to improve detection. The classification models yielded a mean prediction accuracy (F-score) of 0.90 (0.87 to 0.92) at Site 1 and 0.87 (0.81 to 0.91) at Site 2. Results show that the expansion of IPS is closely related to the presence of corridors (e.g., roads, power lines) and to environments disturbed by human activity such as land clearing. Full article