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• Wilding pines in the Cape Floristic Region cover approximately 130,000 condensed hectares. • Wilding pines negatively reduce water resource, change fire regimes and impact biodiversity. • Funding and management of wilding pines are insufficient. • Balancing conservation and economic interests remains a challenge. • More effort needed to secure funding and to enhance collaboration between forestry and conservation. The occurrence and continuing spread of wilding pines (genus Pinus) in the Cape Floristic Region (CFR), South Africa, impacts negatively on water resources, threatens the region's rich biodiversity, and increases the damage caused by uncontrolled wildfires. The invasive potential and threat of wilding pines has been regularly reported since the 1940s, leading to the development and implementation of various control strategies. The last substantial review of pine invasions and their management in the CFR (in 2012) recommended several actions, including securing more sustainable funding and adopting alternative control methods. We review the last 12 years of wilding pine research and management in the CFR, and provide updates on spread and impact, government funding, payments for ecosystems services initiatives, and contributions of the South African Forest industry. We note an increase in private funding, specifically to address invasion in priority catchment areas in the Greater Cape Town region, as well as a recent decline in government funding. Steps have also been taken to revive research aimed at biological control of pines originating from the Iberian Peninsula. The forest industry has deployed species with lower fecundity in some parts of the CFR and has also started experimenting with hybrids that could potentially be less invasive. New methods for applying herbicides may prove to be more efficient than currently used methods. We discuss five opportunities for addressing current shortcomings in the management of wilding pines, namely broadening sources of funding to increase sustainability, effectively integrating all available management techniques, accommodating the need for commercial forestry, focussing scarce funds on priority areas, and raising awareness. We stress that failure to contain rampant invasions by wilding pines will have far-reaching consequences for conservation in the CFR. [ABSTRACT FROM AUTHOR]

The urban landscape is often designed for its aesthetic appeal, yet the vegetation in these environments performs crucial ecological functions in maintaining biodiversity. In this study, we evaluated the availability of nectar-producing plants utilized by hummingbirds in an urban area of southern Brazil. This study examines the richness of plant species, the ratio of native to exotic plants, their flowering seasons, and the hummingbird species that inhabit this urban area throughout the year. The urban area evaluated here follows the common pattern of having a combination of native and exotic plants being utilized by generalist hummingbird species. We recorded twenty-seven plant species used by six hummingbird species in the urban area. Exotic plant species represented a more stable supply of resources over the months, although a native plant species was visited by the highest number of hummingbird species. In addition to heavy anthropogenic pressure, the local urban vegetation evaluated is often subject to intensive management, with frequent pruning of trees and shrubs, as well as plant species suppression and replacement, making the resource supply less stable and predictable over time. [ABSTRACT FROM AUTHOR]

Plants host diverse assemblages of fungi on their foliar tissues, both in internal compartments and on exterior surfaces. When plant distributions shift, they can move with their fungal associates (i.e., co‐introduction) or acquire new associates present in the novel environment (host‐jumping). The fungal communities that plants acquire influence a plant's ability to establish and spread in this new environment. Here, we aimed to assess whether invasive C. ciliaris hosts similar groups of fungi in its native and introduced ranges and to evaluate community overlap of fungi associated with foliar tissue of C. ciliaris and native and non‐native plants within the introduced range. In the introduced range, the majority of OTUs associated with C. ciliaris were not found in its native range, although 3.2% of OTUs were common to both ranges. Of these shared OTU, 77.6% were found on co‐occurring natives and non‐natives in the introduced range, whereas 22.4% were unique to C. ciliaris indicating a possible co‐introduction. Fungal communities within the introduced range contained a higher proportion of generalist symbionts and increased heterogeneity of foliar communities than in its native range. Within the introduced range, host phylogenetic distance explained more variation than native status. Our findings provide evidence that non‐natives acquire fungi opportunistically from their environment, although host and environmental filtering is present suggesting that successful invasive plants may be able to limit the effect of poor symbionts and select for better ones. Future experimental work will be needed to confirm the occurrence of host selection and identify its mechanisms. [ABSTRACT FROM AUTHOR]

Invasive alien plants pose a great threat to local plants and ecosystems. How to effectively alleviate this hazard is an unresolved issue. This study explored the carbon release characteristics of an invasive plant Spartina alterniflora and evaluated the ability of nitrogen removal from shrimp culture wastewater through constructing seawater wetland. The results showed that fresh S. alterniflora had a significantly higher carbon release potential and bioavailability than that of withered S. alterniflora, and alkali-heat treatment could increase the carbon release with an average COD release rate of 33.39 mg/g from fresh S. alterniflora. The removal rate of total nitrogen was improved by about 22% in seawater constructed wetlands by adding fresh S. alterniflora biomass. Moreover, the addition of fresh S. alterniflora biomass was beneficial to the increase in the abundance of denitrification-related genera Vibrio, which might be the key to the improvement of nitrate removal efficiency in seawater constructed wetland systems. These findings indicated that invasive plants S. alterniflora as carbon sources of seawater wetland was a feasible and effective resource utilization strategy. [ABSTRACT FROM AUTHOR]

Globally, the majority of ecosystems are being invaded by multiple co‐occurring alien species. While most of the quantitative syntheses have focused on single invasive species impacts, a global‐scale quantitative synthesis on the interaction effects of species co‐invasions across multiple taxa and levels of ecological organization remain largely unexplored. We address this knowledge gap by synthesizing quantitative information from 256 effect sizes published in 36 studies, that reported the individual and interaction effects of co‐occuring alien plant and animal species. Although, our meta‐analysis showed that the mean interaction effect of co‐invasions across a range of variables was antagonistic (i.e. combined effect less than the sum of individual effects), the vote‐counting revealed additive interaction effects (i.e. combined effect equal to the sum of individual effects) to dominate individual observations. Also, the frequency of interaction effect types varied significantly with response variables, ecological organization, ecosystems, continents and study design, thereby indicating the role of these ecological characteristics in shaping co‐invasion interaction effects. Synthesis. Overall, our synthesis highlights the need for incorporating local ecological complexities in future co‐invasion impact research to better predict their interaction effect on biodiversity and ecosystem functioning across spatio‐temporal scales. Looking ahead, we call for concerted research efforts on the ecological impacts of co‐invasions to unravel the causes of variability in interaction outcomes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Beak deformation, known as avian keratin disorder (AKD), can impair feeding and preening of birds, reducing their survival. This disorder is apparently caused by Poecivirus infection, although to date, the viral origin has been corroborated in only a few North American bird species. Considering that fruit‐eating birds can track spatiotemporal variations in fruit abundance and that AKD may have a viral origin, the incidence of this disease can be expected to increase with flocking by birds. Therefore, we evaluated if austral thrushes (Turdus falcklandii) were attracted to urban areas when exotic plants offered fruits and if flocking of thrushes in urban areas increased the spread of AKD in this species in a Patagonian town. We fitted GPS loggers on some individuals with normal beaks in rural areas and found that they visit the town in fall. Through point count censuses, we recorded greater abundances of thrushes with normal and deformed beaks during fall–winter in urban sites than in rural sites. However, the abundance of birds with AKD declined more (78–87%) than that of individuals with normal beaks (44–52%) during the transition from fall–winter to spring–summer. In urban zones in our study area, fruits of exotic species ripen during fall, attracting austral thrushes from rural sites. Nevertheless, such an attraction for food resources may be an ecological trap for this species, as the increase in incidence of AKD in urban areas may drastically reduce the survival of birds during the most unfavorable period of the year. [ABSTRACT FROM AUTHOR]

Ecological restoration often requires exotic invasive plant control. In many ecosystems, reestablishment of biological soil crusts (biocrusts) is a desired restoration outcome because biocrusts enhance ecosystem function and may favor native plants over exotics. We sought to pair exotic plant suppression with biocrust restoration using a novel restoration material: biocrust‐covered weed barriers. We tested five different barriers, including three biodegradable weed barriers, one synthetic weed barrier commonly used in the study area, and burlap cloth, because it has previously been shown to be useful in biocrust establishment. We grew biocrust moss over the surface of each barrier type in a fog chamber. Each barrier type was attached to the ground in the field with moss on the underside of the barrier (moss‐down), the top, or not present. We monitored the establishment of moss biocrusts and exotic plants and the durability of the barriers. The most successful barrier type for biocrust establishment was burlap, but one biodegradable weed barrier made of maize‐derived polylactic acid (corn) promoted biocrusts, especially in the moss‐down position. Only the synthetic weed barrier suppressed exotic plants for two growing seasons. The corn barrier only partially suppressed exotic plants for one growing season. Less durable weed barriers were less able to suppress exotic plants. Though we failed to identify a biodegradable barrier that both stimulates biocrust recovery and suppresses exotic plants beyond one growing season, our results suggest that our goal may be attainable if more durable biodegradable weed barriers were used or created. [ABSTRACT FROM AUTHOR]

The pyrolysis of water hyacinth is gaining attention and acceptance as a resource recovery technique due to its availability and economic viability. However, the presence of lignin, one of the three major biomass fractions, presents significant challenges for profitable water hyacinth processing for biofuel production. Fungal pretreatment of water hyacinth for lignin breakdown has been explored but the application of Trichoderma atroviride as a pretreatment for pyrolysis is relatively novel. The efficacy of T. atroviride pretreatment in improving water hyacinth's pyrolytic products using a fixed‐bed reactor was therefore investigated in this study. The optimization process was studied using a central composite design in response surface methodology with Design Expert 13. Delignification of the biomass was established because the elemental analysis showed a 25.42% increase in cellulose content and a 23.40% and 3.37% decrease in lignin and hemicellulose content, respectively. The biomass pretreatment applied influenced the physical and chemical characteristics of the pyrolytic products. The highest pyrolysis oil yield increased by 25.81% at 575 °C and particle size 2290 μm, and the highest char yield decreased by 4.23% at 273 °C and particle size 1500 μm. This research is crucial for policy and research conversations as it offers a scientific basis for the application of T. atroviride pretreatment in biomass pyrolysis technology and emphasizes the optimal utilization of water hyacinths to obtain socio‐environmental benefits. [ABSTRACT FROM AUTHOR]

The invasion of plant species is considered to be one of the most dangerous forces in biodiversity change and alteration of soil properties. Due to their significant impact on ecology and the economy, it is important to find an effective approach to manage invasive plant expansion and utilize them as a beneficial biomass source. This review focuses on the characterization of the negative and positive features of invasive plant species in general. Most studies focus on invasive species removal and lack an evaluation of their potential in modern biotechnologies. Currently, there are studies aimed at investigating their use in soil remediation, medicine, the chemical industry, the textile industry, and even gastronomy. Based on these reviews, we bring forward possible future developments in this research field which might serve as a theoretical premise for further research. [ABSTRACT FROM AUTHOR]

The broad-scale inventories of alien species reveal macroecological patterns, but these often fall short in guiding local-level management strategies. Local authorities, tasked with on-the-ground management, require precise knowledge of the occurrence of invasive species tailored to their jurisdictional boundaries. What proves critical at the local scale may not hold the same significance at national or regional levels. In this context, we present a comprehensive inventory of alien vascular plant species across the ecologically diverse Jammu, Kashmir, and Ladakh (JKL) regions of India. Our study identifies 312 alien plant species belonging to 210 genera and 61 families. These alien plant species are predominantly herbaceous dicots. Of these, ca. 62% are naturalized, and 28% exhibit invasive behavior in the region. Introductions have been primarily unintentional, with a notable fraction (26%) introduced for ornamental purposes. The families with the highest number of alien plant species are Asteraceae (46 species), Fabaceae (28 species), and Amaranthaceae (23 species). The genera with the most species are Amaranthus (10 species), Solanum (8 species), Iris (7 species), and Oenothera (5 species). The Jammu region has the highest number of alien plant species, with 221 documented species, including 99 unique to this region. This is followed by the Kashmir Himalaya, with 212 alien species, 70 of which are exclusive to the area. In Ladakh, 76 alien species are recorded, with only one exclusive to the region. Fifty-five alien species are common across all three regions. In each region, more than 50% of species are naturalized, while invasive species constitute about 30% of the total. Therophytes are the dominant life-form category across all regions. Only 18% of species are shared across the three regions. Our findings emphasize the imperative of integrating local-scale knowledge into invasion management frameworks, ensuring targeted and effective strategies aligned with local administrative capacities. By bridging the gap between broad ecological patterns and localized management needs, our study advocates for a nuanced approach to invasive species management that accounts for regional and local specificity. [ABSTRACT FROM AUTHOR]

Plant invasion is a leading threat to biodiversity, ecosystem services and human wellbeing worldwide. In the central Himalayas intentionally or accidentally introduced invasive alien plant species (IAPS) facilitate their own establishment and spread, which is altering forest structure, vegetation composition, species diversity and livelihood. To understand the perception and awareness amongst local communities about invasive alien and native plants and its effect on local livelihood, a questionnaire-based study was conducted in 10 villages of Nainital district, Uttarakhand, India. Household data of 179 respondents were triangulated with key informants such as community leaders, teachers and older people. A majority of the respondents were found to be more familiar with the native species (Berberis asiatica, Pyracantha crenulata and Rubus ellipticus) than IAPS (Ageratina adenophora and Lantana camara). Both the IAPS negative impacts on native biodiversity, ecosystem services and livelihood. During the last two decades IAPS have encroached on various forests and caused a decrease in native species in the study area. According to the local perception, deforestation, forest fire, climate change, increased transport, light weight seed, no use and grazing etc. have been the main factors behind the spread of IAPS. A. adenophora invaded both chir pine (Pinus roxburghii) and banj oak (Quercus leucotrichophora) forests while L. camara remained more prominent in low elevation open canopy chir pine forest. Uprooting is the primary method used to control IAPS in crop fields and forests. The studied villages have not reported awareness and education programs about the IAPS. Our study demonstrates the wide range of perspectives on the threat posed by IAPS to forest ecosystems and natural resources. Education could help to raise awareness about the issue and could be beneficial in managing and controlling invasion in the Himalayan region. [ABSTRACT FROM AUTHOR]

Background: Biological invasions pose an escalating threat to native ecosystems. The accumulation of invasive alien plants worldwide is not saturated yet, underscoring the persistent and growing impact of invasions. Soil microorganisms play a key role in the process of alien plant invasion. However, the temporal dynamics of microbial communities has rarely been determined during the invasion owing to the dearth of long-term, in situ experimental systems. Results: Here, we examined the temporal succession of soil microbial communities 8 years after experiment setup in a common garden. Bacterial communities displayed divergent temporal succession, with invasive plants exhibiting higher turnover rates. Invasive alien plants reduced stochasticity in bacterial communities, likely acting as an environmental filter on community assembly. Plant growth-promoting microbes underwent higher succession rates in invasive alien plants compared to native plants, suggesting that invasive alien plants may possess a distinct advantage in fostering a favorable microbiota for their own growth and establishment. In sharp contrast, native plants selectively increased succession rates of specific plant pathogens. Furthermore, the microbial co-occurrence network was more complex in invasive plants, suggesting that invasive plants foster intricate relationships among microbial communities. Conclusions: Therefore, the asymmetric succession in soil microbial communities enables invasive plants recruit beneficial microbiota from the surrounding soil. These results deepen our understanding of the mechanism underlying plant invasion and provide novel insights into predicting the ecological consequences resulting from widespread plant invasion. This knowledge can be incorporated into management strategies to address the evolving challenges posed by invasive plants. 5vpGYAwD-uHSvdMdk78npk Video Abstract [ABSTRACT FROM AUTHOR]

Anthropization worldwide is increasingly homogenizing biodiversity, i.e., impoverishment of phylogenetic and functional diversity. This study aimed to assess plant phylogenetic relationships of riparian communities in anthropogenically disturbed and undisturbed sites across Continental Portugal. For the analyses, we used 947 species distributed in 205 undisturbed sites and 180 disturbed sites sampled in 100 m plots distributed throughout the country. Then, we assessed the phylogenetic diversity and structure, evolutionary distinctiveness (ED), and conservation of functional traits (life forms) and geographic origin (alien or native) in each site. Our findings. Indicated a higher phylogenetic diversity (higher scores for PD, MPD, MNTD and their standardized effect size) and ED in the undisturbed sites compared to the disturbed ones. The lower phylogenetic diversity in the disturbed sites also relates to the phylogenetic conservatism we found for the lineages of alien and hydrophyte species, which increases the diversity homogenization in those sites. On the other hand, we also recorded higher aliens' ED for the undisturbed sites. Based on the results, we conclude that although the undisturbed sites still harbor higher phylogenetic diversity, they also require monitoring to track the spread of alien species from phylogenetic distant lineages (i.e., high ED) that might thrive in the native communities. [ABSTRACT FROM AUTHOR]

The direction and intensity of plant–soil feedbacks (PSFs) and the reciprocal effects between plants and soils can change over time. PSFs can also affect competition between invasive and native plants. However, most PSF research is conducted in simple experimental settings where temporal changes are not considered. Few studies have assessed the temporal dynamics of PSFs among invasive plants, newly introduced plants and native plants. Here, we conducted a two‐stage PSF experiment to evaluate the temporal dynamics of PSFs among the invasive alien Phytolacca americana, the non‐invasive alien Phytolacca icosandra, and native Phytolacca acinosa. We conducted the experiment with different conditioning time periods. First, we planted the three species individually in pots to condition the soils. Then, each species was grown in a pot conditioned by the same species (‘home soil') or pots conditioned by one of the other two species (‘away soil'). Invasive and native plants produced higher biomass in home soils while non‐invasive alien plants produced higher biomass in away soils. The direction and intensity of PSFs varied with conditioning time among the three species and conditioning time had a significant effect on plant total biomass. Furthermore, sterilizing soils or adding activated carbon altered plant–soil feedbacks, indicating a role for microbes and allelopathic substances in mediating temporal changes. Our study indicates that changes in microbes and allelopathic substances in soils drove temporal changes in PSFs. Invasive alien plants can amplify their competitive advantage through PSFs and also potentially favor establishment of new non‐invasive alien plants. [ABSTRACT FROM AUTHOR]

Invasive alien species play a major role in biodiversity decline. We studied the impacts of invasive alien plant species (IAPS) on bird assemblages and their habitats in Jalthal Forest, a biogeographically unique lowland remnant forest in eastern Nepal. We surveyed birds by point counts and quantified environmental variables at 89 sites. Observations of 1,373 individuals of 86 species showed that species richness was the highest in wooded grasslands and floodplains and lowest in sal forests invaded by IAPS, whereas abundance was highest in IAPS-invaded forests. Abundance and richness decreased with increasing cover of IAPS, shrub cover and distance to water. The abundance and richness of every feeding guild except omnivores were negatively correlated with IAPS cover. Our results increase our understanding of the impacts of IAPS on birds and clearly indicate the need of controlling IAPS in Jalthal Forest, and thus, are valuable for forest management and biodiversity conservation. [ABSTRACT FROM AUTHOR]

Functional traits, which shift as a plant develops from seed to adult and may be phylogenetically conserved, are widely acknowledged to be associated with exotic species invasion. However, existing studies comparing functional traits between native and invasive species often focus on a single ontogenetic stage, yielding mixed results. It remains unclear whether the functional trait differences and their relationship with invasiveness (e.g. range size) of exotic species remain consistent across ontogenetic stages.In this study, we experimentally compared 18 traits across the seed, early growth and adult stages of 127 native and exotic species from 19 families. These species are common and often co‐occur in the subtropical region of China. We also explored the linkage between these traits, alongside their phylogenetic relatedness with native species and exotic species' range size in China.Our results show that only seed mass differed between native and exotic species. Moreover, the compositions of traits across all stages and the entire lifespan were primarily influenced by phylogenetic relatedness rather than geographic origin. Further, the range size of exotic species in China positively correlated with their mean phylogenetic distance to native species, with no association with individual functional traits or functional distinctiveness.Synthesis. Our results emphasize the importance of comparing functional traits across ontogenetic stages between native and exotic species to improve our understanding of the role of functional traits in shaping plant invasion. Our findings also underscore the pivotal role of phylogenetic relatedness in shaping plant functional traits and the distribution of exotic species in their new ranges. [ABSTRACT FROM AUTHOR]

Phytotelma refers to the water accumulated in certain plant structures that constitute the main natural microhabitats for the development of mosquitoes. This study aimed to identify native and exotic plants with phytotelmata and their mosquito fauna (Diptera, Culicidae) in a subtropical area of northeastern Argentina, looking for new records of plant-mosquito associations. The samples were collected bimonthly during 2015-2017 at two sites in each of three localities in the Formosa, Corrientes and Chaco provinces. Species of Apiaceae, Araceae, Arecaceae, Bromeliaceae, Fabaceae, Poaceae and Strelitiaceae were identified as having phytotelmata and all except the latter harbored mosquitoes. Most woody phytotelmata were found in native bamboo Guadua chacoensis (Poaceae), which harbored six culicid species mainly of the Sabethini tribe. The herbaceous phytotelmata with the highest abundance were found in native Aechmea distichantha (Bromeliaceae), which harbored four culicid species, most of the Culicini tribe. New records of culicids that inhabit native phytotelmata in Argentina include Haemagogus spegazzinii in Prosopis nigra and Culex coronator in Acrocomia aculeata, and in exotic phytotelmata include Wyeomyia codiocampa and Toxorhynchites theobaldi in Bambusa vulgaris. Furthermore, two species of the Microculex subgenus were found in Alocasia macrorrhiza and one in Aechmea miniata. The diversity of native plant species with phytotelmata is an important factor in supporting a diverse assemblage of Culicidae, playing a relevant role in the conservation of mosquito diversity. [ABSTRACT FROM AUTHOR]

Invasive alien cacti threaten indigenous biodiversity and negatively impact agricultural productivity in the Eastern Cape Province. One of the most problematic species is jointed cactus, Opuntia aurantiaca Lindley (Cactaceae). A biological control agent, the cochineal insect Dactylopius austrinus De Lotto (Dactylopiidae), is mass-reared and released against O. aurantiaca in the province. The aim of this study was to evaluate the efficacy and safety of D. austrinus against O. aurantiaca through post-release monitoring as perceived by land-users. Post-release monitoring indicated that the number of cladodes of O. aurantiaca declined from 30 (SE ± 1.1)/m2 to 5 (SE ± 1.7)/m2 during a 30-month study period. Forty-seven land-users who had received D. austrinus for O. aurantiaca were interviewed with standardised questionnaires. Most land-users perceived biocontrol as effective, with 71% of land-users reporting a decrease of O. aurantiaca after the release of D. austrinus, and 62% of land-users indicating that the reduction in O. aurantiaca had resulted in environmental and agricultural benefits. Ninety-four per cent of the land-users perceived biocontrol as a safe method without non-target impacts. This study confirms that biological control has been accepted by land-users and they believe it is effective and that mass-rearing of the agent should be increased so that more releases can be made. [ABSTRACT FROM AUTHOR]

The document from the EPPO Bulletin outlines inspection procedures for consignments of plants for planting to prevent the import of regulated invasive plants. It highlights the threat of invasive alien plant species to biodiversity and agricultural systems, particularly through the horticulture trade. The document provides detailed guidance on inspection, sampling, and identification of invasive alien plants, emphasizing the importance of accurate identification and proper hygiene measures during inspections. Additionally, it includes tables listing specific invasive alien plant species of concern for the EPPO region and provides information on growing media types that may facilitate the survival of invasive alien plants. [Extracted from the article]

We compiled bird feeding records in Lima City (Peru) through an in-depth review of online citizen science platforms. Additionally, we analyzed bird-plant interaction networks to assess how the origin status of bird and plant species, as well as species with ornithophilous flowers, contribute to structuring those interactions. The compiled records encompassed 43 bird species and 96 food resources. The native Amazilis amazilia and the exotic Forpus coelestis were the most recorded birds, accounting for 21.5% and 9.9% of the total feeding records, respectively. Plants were the most frequent resource, making up 82.7% of feeding records, while the rest corresponded to insects, fish, and other uncommon cases. Nectarivory and frugivory were the main bird-plant interactions observed. Interaction network analyses for general bird-plant interactions and nectarivory interactions did not show significant modular or nested structures in either case and were highly disconnected. At the species level, the measure of centrality did not significantly differ between exotic and native plants, as well as birds. This suggests that these groups contribute almost equally to maintaining bird-plant interactions. However, for nectarivory interactions, plants with ornithophilous flowers had greater importance in the network, as indicated by their higher centrality values. [ABSTRACT FROM AUTHOR]

Background and aims: Naturalized alien and native plants can impact each other directly when they grow next to each other, but also indirectly through their soil legacies. These alien-native interactions can also be modified by the presence of a third alien or native species. However, it is unknown how the performance of co-growing alien and native species is affected by their soil legacies and by the presence of an additional species. Methods: In our two-phase plant-soil-feedback experiment, soils were first conditioned by eight herbaceous species, four of which are naturalized and four of which are native to Germany. We then grew all 16 pairwise alien-native species combinations on soil conditioned by the respective alien or native species, on a mixture of soils conditioned by both species or on control soil. Each pair of test plants was grown on these soils without or with an additional alien or native species. Results: Soil conditioning, and particularly conspecific soil conditioning, reduced growth of the alien and native test plants. The addition of another species also reduced growth of the test plants. However, the negative conspecific soil-legacy effect on alien test plants was reduced when the additional species was also alien. Conclusion: The negative conspecific plant-soil feedback for alien and native plants in our study could promote their coexistence. However, as partial alleviation of negative conspecific effects on alien plants occurred with an additional alien species, the chances of coexistence of alien and native species might decrease when there are multiple alien species present. [ABSTRACT FROM AUTHOR]

Based on fieldwork in May and June 2024, a number of alien taxa are reported as new to Crete (or even to Greece in general): Bidens subalternans, Commelina erecta, Datura wrightii, Dimorphotheca ecklonis, Euphorbia cyathophora, Leucaena leucocephala, Oenothera rosea, Paraserianthes lophantha, Senecio angulatus and Washingtonia robusta. For a number of other alien taxa that have only recently been known from Crete (Cenchrus longisetus, Euphorbia hypericifolia and Vachellia farnesiana), new locations are presented and/or their degree of naturalization is updated. Taking into account previous experiences in climatically similar regions, almost all of these species have the potential to become invasive in Crete in the near future. [ABSTRACT FROM AUTHOR]

The release of allelochemicals is one of the contributing factors to the success of invasive plants in their non-native ranges. It has been hypothesised that the impact of chemicals released by a plant on its neighbours is shaped by shared coevolutionary history, making natives more susceptible to "new" chemicals released by introduced plant species (novel weapons hypothesis). We explored this hypothesis in a New Zealand system where the two invasive plants of European origin, Cytisus scoparius (Scotch broom) and Calluna vulgaris (heather) cooccur with natives like Chionochloa rubra (red tussock) and Leptospermum scoparium (mānuka). We characterised the chemical composition of root extracts of broom, heather, red tussock and mānuka using gas chromatography–mass spectrometry and then investigated the influence of aqueous root extracts at different concentrations (0.1%, 1%, 5%, 50% and 100% v/v) on mānuka seed germination and seedling growth (root and shoot length and biomass), using deionised water as control. The results show clear distinctions in the chemical composition of the four plants' root extracts, with 4-O-methylmannose dominating the broom extract and (E)-pinocarveol the heather extract, while 16-kaurene and methyl palmitate were abundant in both mānuka and tussock extracts. We found a significant effect of invasive plant (heather and broom) root extracts on mānuka germination at all concentrations tested, and adverse effects on seedling growth and biomass only at higher concentrations (≥ 5%). Broom displayed stronger allelopathic effects than heather at the highest concentration (100%). For extracts of conspecific and other native species (mānuka and red tussock) allelopathic effects were only observed at very high concentrations (50 and 100%) and were generally weaker than those observed for invasive plants. These results show that while both native and invasive plants produce chemicals with allelopathic potential, native species are likely to be more vulnerable to the allelopathic effects of species they did not co-evolve with, supporting the novel weapons hypothesis. However, this study also highlights differences in allelopathic potential between invasive species. [ABSTRACT FROM AUTHOR]

One of the characteristic features of urban floras is their homogenization, which is synonymous with the loss of regionally unique species and a reduction in functional diversity. Here we examined the species composition of native and alien species in the flora of Russian cities to identify the contribution of these groups of species to the homogenization and differentiation of urban floras. The results we obtained showed that the species similarity of urban flora depends on the distance between cities—urban flora of geographically close cities have the lowest species dissimilarity. This distance-dependence is highest for neophytes dissimilarity and lowest for archeophytes dissimilarity. Thus, the homogenization of the species composition of the Ural and Volga region urban floras is provided mainly by archeophytes, while a group of neophytes increases the β-diversity of urban flora. [ABSTRACT FROM AUTHOR]

Parrot feather (Myriophyllum aquaticum) is an introduced, noninvasive amphibious plant found in coastal provinces, but it has the potential to become an invasive species in China. The plant is heterophyllous, with both emergent (aerial) and submerged (aquatic) leaves, and has two distinct root types: aquatic (adventitious) and edaphic (sediment) root systems. This morphological plasticity allows M. aquaticum to effectively absorb nutrients from different layers of the environment, making it a suitable model plant for exploring nutrient dynamics in both water and soil systems and investigating how wetland plants respond to cultural eutrophication. We designed an outdoor mesocosm experiment to assess plant growth traits and root topological indices in response to different nitrogen (N) and phosphorus (P) concentrations. The results indicated that the plant has a high tolerance to N loading. In contrast, the P content had greater impacts than the N content on plant growth and root topological indices, indicating that the P content was the main influencing factor affecting and suppressing the development of M. aquaticum. The aquatic or edaphic root branching did not change, but the aquatic root topology of M. aquaticum exhibited similar stable trends with increasing P concentration, indicating typical herringbone branching; additionally, its edaphic roots exhibited decreasing topological indices, indicating more typical dichotomous branching with increasing P concentration. The plant has a high tolerance to N, and it may become invasive following the current trend of increasing cultural eutrophication. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) present a significant threat to ecosystems and agricultural production, necessitating rigorous monitoring and detection for effective management and control. To realize accurate and rapid detection of invasive alien plants in the wild, we proposed a rapid detection approach grounded in an advanced YOLOv9, referred to as YOLO-IAPs, which incorporated several key enhancements to YOLOv9, including replacing the down-sampling layers in the model's backbone with a DynamicConv module, integrating a Triplet Attention mechanism into the model, and replacing the original CIoU with the MPDloU. These targeted enhancements collectively resulted in a substantial improvement in the model's accuracy and robustness. Extensive training and testing on a self-constructed dataset demonstrated that the proposed model achieved an accuracy of 90.7%, with the corresponding recall, mAP50, and mAP50:95 measured at 84.3%, 91.2%, and 65.1%, and a detection speed of 72 FPS. Compared to the baseline, the proposed model showed increases of 0.2% in precision, 3.5% in recall, and 1.0% in mAP50. Additionally, YOLO-IAPs outperformed other state-of-the-art object detection models, including YOLOv5, YOLOv6, YOLOv7, YOLOv8, YOLOv10 series, Faster R-CNN, SSD, CenterNet, and RetinaNet, demonstrating superior detection capabilities. Ablation studies further confirmed that the proposed model was effective, contributing to the overall improvement in performance, which underscored its pre-eminence in the domain of invasive alien plant detection and offered a marked improvement in detection accuracy over traditional methodologies. The findings suggest that the proposed approach has the potential to advance the technological landscape of invasive plant monitoring. [ABSTRACT FROM AUTHOR]

Riparian softwood forests support numerous ecological functions and high biodiversity. In the context of the LIFE+ Traisen project, a non-regulated new riverbed for the lower Traisen River ("New Traisen") was created within an artificially lowered floodplain corridor. Using vegetation monitoring from 2014 to 2021, we determined (i) the role of Solidago gigantea in the establishment of softwood forests, (ii) the habitat parameters (such as flooding height, fine substrate layer thickness, and vegetation cover) that impact the establishment and growth of woody plants, and (iii) the successional phase at which woody plants become established, as well as the potential creation of new germination habitats. During early succession, the softwood species, as light-tolerant pioneer species, colonized the open sites together with S. gigantea and subsequently established a floodplain softwood forest. Unexpectedly, we observed negative forest development only when the S. gigantea cover exceeded 90%. Neither the habitat parameters nor S. gigantea cover significantly impacted tree occurrence. However, we highlight the need for optimum habitat parameters for softwood forest development in early succession phases, ideally before S. gigantea forms dense, monospecific stands. Tailored monitoring strategies are needed to guide the succession of such semi-aquatic habitats toward the development of the desired habitat type. [ABSTRACT FROM AUTHOR]

Biological invasion is the second most important threat to biodiversity and consequently is a cause of great concern for the ecology and economy of the invaded community. Documentation of invasive plants in a region is crucial as it provides the baseline information for future research and management activities. In this study, we have produced an annotated checklist of the invasive alien plants of Gorakhpur district in the Terai region of Eastern Uttar Pradesh based on field observation, existing literature, and herbarium consultation. A total 58 alien plants species are listed, belonging to 25 angiosperm families of which 15 alien species are invasive having high impact, 37 alien species are naturalized having moderate impact and 6 alien species are casual having low impact over ecological communities. All the invasive plants are not equally problematic and spread across the district while some of them viz. Ageratum houstonianum Mill., Alternanthera philoxeroides (Mart.) Abh., Chromolaena odorata (L.) R.M. King & H. Rob., Mesosphaerum suaveolens (L.) Kuntze., Mikania micrantha Kunth Nov., Parthenium hysterophorus L., Pontederia crassipes Mart., Antigonon leptopus Hook. & Arn., Lantana camara L., are spread in most parts of the district and they are capable of spreading into the protected areas of this region. The present study is based on firsthand field observations, and provides a detailed and recent checklist of invasive species of Gorakhpur district. Therefore, this information can help researchers and policymakers to develop effective management strategies. [ABSTRACT FROM AUTHOR]

Exotic plants can selectively recruit beneficial microorganisms, such as arbuscular mycorrhizal fungi (AMFs) and Bacillus spp., during their invasion process to enhance growth and competitiveness by improving nutrient absorption and strengthening defense capabilities against herbivores. However, research in the context of invasive plants remains limited. In this study, a greenhouse pot experiment was conducted to examine the effects of different treatments on the growth and defense of Ageratina adenophora. The treatments included no inoculation, inoculation with Bacillus thuringiensis (BT), inoculation with arbuscular mycorrhizal fungus (Claroideoglomus etunicatum, CE), dual inoculation with BT and CE (BT + CE), and the presence or absence of Procecidochares utilis. The results showed that both CE and BT + CE significantly enhanced nutrient concentration and promoted the growth of A. adenophora. The aboveground biomass increased by 35.48 and 53.38% under non-parasitism and by 68.03% and 103.72% under the parasitism of P. utilis for these two treatments, respectively. In comparison to the control P. utilis-parasitized A. adenophora, the BT, CE, and BT + CE treatments significantly increased protective enzyme activity, jasmonic acid concentration, and secondary metabolites. Our study indicates that the recruitment of B. thuringiensis in the rhizosphere of A. adenophora can enhance its defense ability, while C. etunicatum improved both growth and defense ability. The interaction effects of these two microorganisms enhances the regulation of growth and defense ability of A. adenophora against P. utilis parasitism, providing insights into the feedback effects of beneficial microorganisms on the interactions between invasive plants and biological control. [ABSTRACT FROM AUTHOR]

One threat pollinators face in a rapidly changing climate is the decoupling of their activity period from the blooming period of their host plants. Pollinators active in the earliest part of spring may be especially susceptible, as there are few alternative food resources available if they become active before their host plants begin blooming. Thus, urban landscapes, although often associated with decreased insect biodiversity, may buffer pollinators from such food shortages by offering a diversity of both native and exotic plant species that bloom in the late winter and early spring. However, more data are needed to ascertain the degree to which pollinators utilize flowers of spring-blooming exotic species. Here, we surveyed flower-visiting Hymenoptera and Diptera on 26 flowering plant taxa in three urban botanical gardens in the Oklahoma City metropolitan area in the early spring (March and April). We found that flowers of both native and exotic plants were attractive to Hymenoptera and Diptera, although pollinator visitation rates varied by more than an order of magnitude across plant taxa. Overall, woody plants were more attractive to pollinators compared to herbaceous plants, regardless of whether the plant was native or exotic. Implications for insect conservation: Our results suggest that regardless of native status, urban plants that bloom in the early spring—especially woody species—may be coopted to support pollinators that are especially susceptible to climate change. However, care needs to be taken to select plant species and varieties that pollinators will actually use. [ABSTRACT FROM AUTHOR]

Biological invasions pose a major environmental challenge, often facilitating the unregulated dissemination of pathogens and parasites associated with their hosts. These pathogens can severely impact native and cultivated species, with far-reaching ecological and economic consequences. Despite their importance, the mycobiota associated with invasive plant species remains relatively understudied, posing a complex challenge for researchers. The aim of this manuscript is to underscore the most significant threats posed by the uncontrolled transmission of fungal pathogens from invasive alien plants to native environments and agricultural systems, and to identify the factors influencing this phenomenon. We emphasize the role of pathogen spillback and spillover mechanisms in the domestication of invasive alien plants. The influence of environmental, host, and pathogen-related factors on the survival of fungal pathogens were also investigated. Finally, we explore the technical and legal feasibility of using plant pathogens as "green agents" to control invasive alien plants. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The ability of seeds to germinate under a wide range of environmental conditions is an important characteristic of invasive alien plant species. Solanum rostratum Dunal, has been widely distributed in the Northeast and Northwest of China and is causing huge damage to the local agricultural production. Studies on seed germination and response among populations to environmental stress may assist in revealing the adaptability of invasive plants and how they cope with climate change. In this study, we collected seeds from five invasive plant populations of S. rostratum, with intervals of over 3000 km between them, distributed in different habitats and climate zones. We measured the differences in seed traits between populations and studied the trends in germination responses of S. rostratum seeds under diverse abiotic stress conditions. The weight and size of S. rostratum seeds distributed in Northeast China were significantly greater than those distributed in Northwest China; for the response of S. rostratum seed germination to environmental factors, seeds from arid and extremely arid areas of Northwest China had greater tolerance to high temperatures and osmotic stress, while seeds from semi-arid areas of Northeast China were more sensitive to low temperatures and high salt stress. Overall, the germination of S. rostratum seeds responded differently to various environmental stress factors, reflecting the ability of S. rostratum to occupy germination sites under low resource competition. Given the rapid changes in the global climate, our findings provide new insights into the seed adaptation strategies of alien plants during the invasion process and the mechanisms involved. [ABSTRACT FROM AUTHOR]

In Ethiopia, Parthenium hysterophorus (P. hysterophorus) is an invasive alien plant affecting various ecosystems. P. hysterophorus displaces native plant species and causes a serious threat to biodiversity. With this background, we aimed to assess the soil seed bank of P. hysterophorus under major land use types and assess the perception of the community toward the effects of P. hysterophorus on social aspects in the lower Hare watershed. For this study, 210 soil samples were collected from 15 transect lines in grassland, cropland, and forest land use types. Statistical analysis using three-way factorial analysis of variance (ANOVA) was used to analyze the difference in density of P. hysterophorus among various land uses soil depths and sites (P < 0.05). For assessing the perception of local communities regarding the effects of P. hysterophorus, a total of 117 respondents were enrolled and semi-structured and close-ended questionnaires were used for data collection. It was found that all factors, that is, land use, site, and soil depth, significantly affected the soil seed bank density in the lower Hare watershed (P < 0.05). Results indicated that the mean density of seeds was the highest in croplands among the land use types. Meanwhile, the highest mean density of seeds was identified in 0–10 cm soil depth, but the lowest mean density of seeds was identified in 10–15 cm soil depth. The highest seeds were identified at Chano Cheliba, but the density of seeds the lowest in Kola Shera. Moreover, 38.5% of households in Kola Shera and 21.4% of households in Kola Cheliba, but 8.5% of households in Kola Doriga said that it had effects on ecosystem services such as crop yield and livestock production. There should be a need for increased awareness about the density of P. hysterophorus in various land uses and its impacts on native plant species. Seeking for possible solutions such as mechanical control methods in terms of abortion of its seed set and weeding in early vegetative period are among the local people, researchers, and extension workers can use for the management of its invasion, and appropriate control measures can be designed to combat its further invasion and impacts on different land uses of the region. [ABSTRACT FROM AUTHOR]

Urbanization has reshaped the distribution of biodiversity on Earth, but we are only beginning to understand its effects on ecological communities. While urbanization may have homogenization effects strong enough to blur the large-scale patterns in interaction networks, urban community patterns may still be associated with climate gradients reflecting large-scale biogeographical processes. Using 103 hummingbird–plant mutualistic networks across continental Americas, including 176 hummingbird and 1,180 plant species, we asked how urbanization affects species interactions over large climate gradients. Urban networks were more generalized, exhibiting greater interaction overlap. Higher generalization was also associated with lower precipitation in both urban and natural areas, indicating that climate affects networks irrespective of habitat type. Urban habitats also showed lower hummingbird functional trait diversity and over/ underrepresentation of specific clades. From the plant side, urban communities had a higher prevalence of nonnative nectar plants, which were more frequently visited by the hummingbird species occurring in both urban and natural areas. Therefore, urbanization affected hummingbird–plant interactions through both the composition of species and traits, as well as floral resource availability. Taken together, we show that urbanization consistently modifies ecological communities and their interactions, but climate still plays a role in affecting the structure of these novel communities over the scale of continents. [ABSTRACT FROM AUTHOR]

Although herbivory and allelopathy play important roles in plant invasions, their roles in mediating the effect of plant diversity on invasion resistance remain unknown. In a 2‐year field experiment, we constructed native plant communities with four levels of species richness (one, two, four, and eight species) and used a factorial combination of insecticide and activated carbon applications to reduce herbivory and allelopathy, respectively. We then invaded the communities with the introduced plant Solidago canadensis L. One year after the start of the experiment, there was no statistically significant net effect of species richness on biomass of the invader. However, a structural equation model showed that species richness had a positive direct effect on invader biomass that was partially balanced out by a negative indirect effect of species richness via increased light interception. In the second year, the relationship between invader biomass and species richness was negative when we analyzed the treatment combination with herbivory and allelopathy separately. Therefore, we conclude that joint effects of herbivory and allelopathy may play major roles in driving the diversity–invasibility relationship and should be considered in future studies. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Methods Results Main Conclusion We aim to investigate whether invasive alien plants introduced at different times exhibit variations in elevational distribution patterns and to explore the correlations of these patterns with climate, native plants and human activity.Guangxi, China.We recorded plant richness and cover across elevational gradients at 25–34 sites within each reserve, utilising 84–134 roadside plots per site. Using generalised linear mixed model (GLMM), we assessed the impacts of climate, native plants and human activity on the distributions of all, old and new invasive alien plants across the region and within the nature reserves.At regional scales, the cover of all, new and old invasive alien plants decreased with increasing elevation, while only the richness of old invasive alien plants exhibited a similar pattern. Contrasting patterns were observed in Dayao Mountain, where the cover of old invasive alien plants decreased while the cover of new invasive alien plants increased. The richness patterns of all and new invasive alien plants were opposite between Dayao Mountain and Yachang Orchid. Moreover, native plant richness was negatively correlated with the richness of invasive alien plants, while interference intensity positively affected new invasive alien plants at both regional and reserve scales. At the regional scale, native plant richness accounted for 78.27%, 91.94% and 60.9% of all, old and new invasive alien plants respectively. Interference intensity accounted for 33.85% of the variation in new invasive alien plants. Annual mean temperature positively influenced the cover of all and old invasive alien plants at both regional and reserve scales, explaining 36.91% and 74.28% of their regional variation. Additionally, interference intensity and distance to human settlements positively impacted the cover of new invasive alien plants, contributing to 50.95% and 31.92% of their variation at regional scales.The distinct distribution patterns of old and new invasive alien plants highlight the significance of residence time in understanding their dynamics. Climate factors constrain the cover distribution of all and old invasive alien plants, whereas interference intensity and distance to settlements determine the distribution of new invasive alien plants. Notably, native plants play a vital role in preventing the establishment and spread of invasive alien plants within nature reserves, and their effectiveness increases with longer residence times. Our findings highlight the critical importance of minimising human interference and conserving native species for the effective management of invasive alien plants in nature reserves. [ABSTRACT FROM AUTHOR]

Invasive alien plants (IAPs) are nonnative species that pose significant threats to the environment by outcompeting native vegetation and disrupting ecosystem functions. Efforts to monitor and eradicate IAPs have been limited due to the challenges in accurately identifying these plants using traditional remote sensing (RS) methods. This paper reviews the literature to identify the most accurate and reliable plant detection methods for IAPs. Advanced searches were conducted on ScienceDirect, Scopus and Institute of Electrical and Electronics Engineers (IEEE) Xplore databases using keywords such as 'Remote Sensing (RS)', 'Machine Learning (ML)', 'Deep Learning (DL)', 'Invasive Alien Plant (IAP)' and 'detection'. The search yielded 1689 articles: 1129 focused on the RS methodologies, 303 on ML, 142 on DL and 115 combining all three approaches. The review found that the RF and support vector machine (SVM) algorithms are the most effective for detecting IAPs. This suggests that future research should prioritize the application of ML and DL techniques, particularly RF and SVM, due to their high potential for improving IAP identification and aiding in their eradication. These advancements align with Sustainable Development Goal (SDG) 15, which emphasizes the protection, restoration and sustainable use of terrestrial ecosystems, and SDG 8, which promotes sustained, inclusive and sustainable economic growth. Effective IAP management not only preserves biodiversity but also creates economic opportunities by improving land value and usability. This review underscores the importance of integrating advanced technological methods in environmental management to support both ecological and economic objectives. [ABSTRACT FROM AUTHOR]

There is increasing recognition that alien species may be 'sleepers', becoming invasive with favourable changes in conditions, yet these changes remain difficult to predict. As populations of frugivorous birds shift with urbanisation and climate change, they could provide dispersal services for introduced fruiting plants that have previously been considered benign. This is likely to be especially problematic at higher latitudes where bird migration phenologies are altering rapidly. However, any consequences for fruit dispersal have not yet been explored. Here, we use Helsinki, Finland, to investigate whether (i) streetscapes provide birds with a fruit resource that differs from urban forest fragments and (ii) the chances for dispersal of alien species (i.e., preferential consumption of native fruits). While there were both more fruits and birds in streetscapes (replicated across multiple years), fruits were not consumed preferentially according to origin. Additionally, seed analysis from faecal samples of blackbird Turdus merula L., a previously migratory but increasingly resident species, suggested that alien and native plants are equally likely to be dispersed. These results indicate that birds could be dispersing alien species more frequently than previously thought and highlight the complex effects of changing climates on potentially invasive species. [ABSTRACT FROM AUTHOR]

Mauritius raspberry (Rubus rosifolius) is an exotic plant cultivated in Indonesia. Studies showed that the productivity of exotic plants is reducing due to a lack of pollination agent for their origin region. Several methods could be applied to overcome this problem. The study aimed to find the most effective method for pollinating this plant among four pollination regimes: Self-pollination, wild insects, stingless bees (Tetragonula laeviceps), and hand-pollination. The observation was conducted on the insect pollinators' activities (visitation rate, flower constancy, and flower handling time), pollination efficiency, and quality of the fruits produced (fruit volume). The results showed a higher visitation rate (10 to 70 per hour), higher flower constancy (visited from 07.00 to 16.00), and longer flower handling time (13.6 s) of T. laeviceps on raspberry flowers than other insects. High activities related to better raspberry pollination success (96%) and bigger fruits produced. Based on this study, applying stingless bees as pollination agents for exotic plants was the best and potentially applicable to other exotic crops. [ABSTRACT FROM AUTHOR]

Why nonnative invasive plant species commonly co‐occur, despite their competitive superiority and propensity to displace native species, remains a paradox in invasion biology. Negative interactions among competitively dominant invaders are potentially alleviated by two understudied mechanisms: seasonal priority effects, where phenological separation weakens the effect of competition on species with early phenology; and indirect facilitation, where competition between two species is mitigated by a third species. Although phenological separation has been speculated as a mechanism for explaining co‐occurrence patterns of invasive plants, it has never been directly tested. In a greenhouse experiment, we tested the effect of phenological separation on direct and indirect interactions between three co‐occurring invasive plant species found in the riparian forests of North America. These species have distinct natural phenological separation with reproduction in early spring (Ficaria verna), mid‐spring (Alliaria petiolata), and late summer (Microstegium vimineum). When phenology was experimentally synchronized, direct pairwise interactions among invasive species were overwhelmingly negative, asymmetric, and unlikely to promote co‐occurrence. However, increasing phenological separation generated seasonal priority effects, which weakened the effect of competition on species with early phenology. Furthermore, the addition of a third species generated indirect facilitative effects, which balanced competitive outcomes among the two weakest competitors. Based on these findings, we conclude that phenological separation modulates the strength of both seasonal priority effects and indirect facilitation within species interaction networks and may promote the co‐occurrence of three common invasive species within this study system. We articulate how future studies can test the external validity of these findings in more complex environmental conditions and with a larger range of invasive plants. [ABSTRACT FROM AUTHOR]

Like alien plant invasion, range expansion of native plants may threaten biodiversity and economies, rendering them native invaders. Variation in abiotic and biotic conditions across a large geographic scale greatly affects variation in traits and interactions with herbivores of native plant invaders, which is an interesting yet mostly unexplored issue. We used a common garden experiment to compare defensive/nutritional traits and palatability to generalist herbivores of 20 native (23.64° N–30.18° N) and introduced range (31.58° N–36.87° N) populations of Reynoutria japonica, which is a native invader following range expansion in China. We analyzed the relationships among herbivore pressure, climate, plant chloroplast haplotypes, leaf traits, and herbivore performance. Of the 16 variables tested, we observed range differences in 11 variables and latitudinal clines in nine variables. In general, herbivores performed better on the introduced plants than on the native plants, and better on the high‐latitude plants than on the low‐latitude plants within the introduced populations. Three key traits (leaf thickness, specific leaf area, and carbon‐to‐nitrogen [C:N] ratio) determined palatability to herbivores and were significantly associated with temperature and/or precipitation of plant provenance as well as with plant haplotypes but not with herbivore pressure. Our results revealed a causal sequence from plant‐range‐based environmental forces and genetic context to plant quality and palatability to herbivores in R. japonica. These findings suggest a post‐introduction evolution of R. japonica, which may partly explain the colonization success of this important native, but invasive plant. [ABSTRACT FROM AUTHOR]

Invasions by nonnative insect species can massively disrupt ecological processes, often leading to serious economic impacts. Previous work has identified propagule pressure as important driver of the trend of increasing numbers of insect invasions worldwide. In the present article, we propose an alternative hypothesis—that insect invasions are being driven by the proliferation of nonnative plants, which create niches for insect specialists and facilitate their establishment outside their native ranges where their hosts are planted or are invasive. We synthesize mechanisms by which plant invasions facilitate insect invasions, macroecological patterns supporting the tight link between plant and insect invasions, and case studies of plant invasions having facilitated subsequent insect establishment. This body of evidence indicates that plant invasions are a major driver of insect invasions. Consequently, the benefits of limiting the spread of nonnative plants include averting the proliferation of nonnative insects and their spillover onto native plant species. [ABSTRACT FROM AUTHOR]

Terrestrial plant communities often become invaded by alien species, which may benefit from high growth rates, strong phenotypic plasticity and reduced negative impacts from local soil communities. At the same time, terrestrial communities are increasingly more often exposed to periods of drought. However, how drought affects the competition between alien and native plants directly, and indirectly, through changing impacts of soil communities on plant performance, remains poorly understood.Here, we performed a greenhouse pot experiment in which we examined biomass responses of five native and five naturalized alien species (all occurring in mesic grasslands) to drought and benign soil moisture conditions, while growing in interspecific, intraspecific or absence of competition, in the presence or absence of native soil biota. We expected that alien plant species are less negatively affected by soil biota, but more negatively affected by drought than native species, and that drought indirectly weakens soil‐community‐driven competitive benefits of alien plant species over native ones.On average, soil‐community effects on plant biomass were positive, but native performance was less positively affected by soil communities than alien performance, suggesting reduced impacts of soil‐borne enemies on alien plants. Drought more negatively affected alien‐ than native plant performance. Drought impacts on plant biomass did not depend on soil community presence, but in the presence of soil biota, plants overall invested more in root biomass when exposed to drought. The effects of competition were subtle and species‐specific.To better understand the observed positive soil‐community effects on plant performance in our study, we examined mycorrhizal root colonization of plants grown in absence of competition. Among‐species variation in mycorrhizal colonization explained plant performance differences between soils with and without live soil communities, indicating a key role for arbuscular mycorrhizal fungi as driver of plant performance. However, mycorrhizal colonization did not differ between alien and native plants and was unaffected by drought.Overall, our study suggests that drought may weaken alien plant invasions through stronger direct negative impacts on alien than on native plant performance, but that drought does not affect soil‐biota‐driven differences in plant performance between alien and native plants. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Phylogeography of invasive exotic plant species is crucial for identifying the source population from which a given invading population has originated. Ardisia crenata Sims, a shade tolerant shrub native to East Asia, is one of the most serious invasive exotic plants in Florida, North America. The objective of this study is to investigate the genetic differentiation and phylogeographical relationships among A. crenata native populations in Japan and invasive populations in Florida. We analyzed DNA from 188 individuals gathered from eight populations in Japan and four subpopulations in Florida using double‐digestion restriction‐associated DNA sequencing (ddRAD‐seq) and estimated a maximum likelihood phylogenetic tree among them. The results revealed four genetic clusters, with a striking dominance of genetically identical clonal individuals within the invading populations in Florida and four Honshu populations in Japan. These groups were genetically close to each other and to one cultivated individual sampled in Japan. In contrast, the individuals from Miyazaki, Yakushima, Kochi, and Iriomote in southwestern Japan were genetically distinct from Honshu and Florida individuals, showing high genetic diversity indicative of outcrossing. Given that A. crenata does not exhibit a vegetative clonal habit and all wild and cultivated plants regenerate from seeds, these results suggest that Honshu and Florida populations exclusively reproduced with seeds produced by apomixis. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The success of ecosystem restoration is often evaluated by the stable establishment and growth of native plants while preventing the spread of alien plants. However, research on the factors and mechanisms controlling the abundance (richness and coverage) of native and alien plants remains limited. To address this, we analyzed data from 167 plots (100 m2) in forest restoration sites in South Korea. We assessed the effects of abiotic factors (topography, climate, and soil), biotic factors, and the number of years integrally since restoration on both plant groups by using a piecewise structural equation model. Native plant abundance was influenced by shrub density (species richness: β = 0.19; coverage: β = 0.20) and available phosphorus (β = 0.19), while alien plant abundance was controlled by soil pH (species richness: β = 0.45), elevation (β = −0.15), species richness, and tree (β = −0.15) and shrub species richness (β = −0.16). The number of years since restoration has indirectly affected native and alien plants through shrub species richness and shrub coverage. Our results indicate that high resource availability, such as light, in the early stages of restoration may allow native and alien herbaceous plants to coexist. However, as vegetation and forest strata develop, reduced light availability can lead to a decline in alien species and the dominance of native plants. We also provide management strategies to suppress alien plants by promoting structural complexity within forest stands. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)