Berberis Thunbergii Research Articles

Analysis and Prediction of Land Use Changes Related to Invasive Species and Major Driving Forces in the State of Connecticut

Land use and land cover (LULC) patterns play an important role in the establishment and spread of invasive plants. Understanding LULC changes is useful for early detection and management of land-use change to reduce the spread of invasive species. The primary objective of this study is to analyze and predict LULC changes in Connecticut. LULC maps for 1996, 2001 and 2006 were selected to analyze past land cover changes, and then potential LULC distribution in 2018 was predicted using the Multi-Layer Perceptron Markov Chain (MLP_MC) model. This study shows that the total area of forest has been decreasing, mainly caused by urban development and other human activity in Connecticut. The model predicts that the study area will lose 5535 ha of deciduous forest and gain 3502 ha of built-up area from 2006 to 2018. Moreover, forests near built-up areas and agriculture lands appear to be more vulnerable to conversion. Changes in LULC may result in subtle spatial shifts in invasion risk by an abundant invasive shrub, Japanese barberry (Berberis thunbergii). The gain of developed areas at the landscape scale was most closely linked to increased future invasion risk. Our findings suggest that the forest conversion needs to be controlled and well managed to help mitigate future invasion risk.

Biotic interactions with natural enemies do not affect potential range expansion of three invasive plants in response to climate change

The ranges of species, including invasives, are expected to shift poleward in response to climate change. As their distributions expand, invasive species will encounter different communities and the resulting biotic interactions could affect invasive species range expansion dynamics. Here, we assess whether biotic interactions with natural enemies have the potential to affect range expansion dynamics of three invasive woody plants (Berberis thunbergii, Celastrus orbiculatus and Elaeagnus umbellata). To do so, we planted them in two sites in a region where they are currently abundant and in three sites in a northern region near their range edge where they are expected to become more common due to climate change. Two of the species have not yet been observed within any of the northern sites and one species is present within one of the northern sites. All species experienced more foliar herbivory in the higher latitude (northern) region and the two species that are currently absent from the northern sites experienced less foliar disease there. However, the regional differences in biotic interactions had very minor effects on survival; the only statistically significant reduction in survival was from foliar disease for B. thunbergii, and even that had only a marginal effect on survival. This suggests that, at least for these invasive species in this area, interactions with existing natural assemblages of natural enemies will have only an exceedingly minor effect on populations establishing near range edges.

Diversity-oriented natural product platform identifies plant constituents targeting Plasmodium falciparum.

BackgroundA diverse library of pre-fractionated plant extracts, generated by an automated high-throughput system, was tested using an in vitro anti-malarial screening platform to identify known or new natural products for lead development. The platform identifies hits on the basis of in vitro growth inhibition of Plasmodium falciparum and counter-screens for cytotoxicity to human foreskin fibroblast or embryonic kidney cell lines. The physical library was supplemented by early-stage collection of analytical data for each fraction to aid rapid identification of the active components within each screening hit.ResultsA total of 16,177 fractions from 1300 plants were screened, identifying several P. falciparum inhibitory fractions from 35 plants. Although individual fractions were screened for bioactivity to ensure adequate signal in the analytical characterizations, fractions containing less than 2.0 mg of dry weight were combined to produce combined fractions (COMBIs). Fractions of active COMBIs had EC50 values of 0.21–50.28 and 0.08–20.04 µg/mL against chloroquine-sensitive and -resistant strains, respectively. In Berberis thunbergii, eight known alkaloids were dereplicated quickly from its COMBIs, but berberine was the most-active constituent against P. falciparum. The triterpenoids α-betulinic acid and β-betulinic acid of Eugenia rigida were also isolated as hits. Validation of the anti-malarial discovery platform was confirmed by these scaled isolations from B. thunbergii and E. rigida.ConclusionsThese results demonstrate the value of curating and exploring a library of natural products for small molecule drug discovery. Attention given to the diversity of plant species represented in the library, focus on practical analytical data collection, and the use of counter-screens all facilitate the identification of anti-malarial compounds for lead development or new tools for chemical biology.Electronic supplementary materialThe online version of this article (doi:10.1186/s12936-016-1313-7) contains supplementary material, which is available to authorized users.

Long-Term Effects of White-Tailed Deer Exclusion on the Invasion of Exotic Plants: A Case Study in a Mid-Atlantic Temperate Forest.

Exotic plant invasions and chronic high levels of herbivory are two of the major biotic stressors impacting temperate forest ecosystems in eastern North America, and the two problems are often linked. We used a 4-ha deer exclosure maintained since 1991 to examine the influence of a generalist herbivore, white-tailed deer (Odocoileus virginianus), on the abundance of four exotic invasive (Rosa multiflora, Berberis thunbergii, Rubus phoenicolasius and Microstegium vimineum) and one native (Cynoglossum virginianum) plant species, within a 25.6-ha mature temperate forest dynamics plot in Virginia, USA. We identified significant predictors of the abundance of each focal species using generalized linear models incorporating 10 environmental and landscape variables. After controlling for those predictors, we applied our models to a 4-ha deer exclusion site and a 4-ha reference site, both embedded within the larger plot, to test the role of deer on the abundance of the focal species. Slope, edge effects and soil pH were the most frequent predictors of the abundance of the focal species on the larger plot. The abundance of C. virginianum, known to be deer-dispersed, was significantly lower in the exclosure. Similar patterns were detected for B. thunbergii, R. phoenicolasius and M. vimineum, whereas R. multiflora was more abundant within the exclosure. Our results indicate that chronic high deer density facilitates increased abundances of several exotic invasive plant species, with the notable exception of R. multiflora. We infer that the invasion of many exotic plant species that are browse-tolerant to white-tailed deer could be limited by reducing deer populations.

A comparative phytochemical and pharmacological analysis of the extracts from leaves of the ukrainian flora shrubs

In the Ukrainian flora such plants as Forsythia europaea Deg. et Bald, Jasminum officinale L., Berberis thunbergii DC, Weigela hybrida Jaeg., Ligustrum vulgare L., and Corylus avellana L. hold a special place among shrubs. The aim of our research was to analyse the relationship between the chemical composition and the anticonvulsant activity of the extracts from leaves of the given shrubs. The highest content of flavonoids has been determined in aqueous extracts of Forsythia europaea (2.83%) and Corylus avellana (1.95%) leaves comparing to other extracts. The highest amount of polyphenols has been determined in Corylus avellana ethanol (96%) extract (1.31%) and Jasminum officinale ethanol (50%) extract (1.30%). The dry aqueous extract of Corylus avellana leaves has shown the most pronounced anticonvulsant activity. Dry extracts of Berberis thunbergii leaves, Weigela hybrida leaves, and Ligustrum vulgare leaves have not revealed a significant anticonvulsant activity. According to the strength of the effect the dry aqueous extract of Corylus avellana can be a promising substance for creating an original herbal remedy with anticonvulsant properties.

Deer feeding selectivity for invasive plants

Native generalist herbivores might limit plant invasion by consuming invading plants or enhance plant invasion by selectively avoiding them. The role of herbivores in plant invasion has been investigated in relation to plant native/introduced status, however, a knowledge gap exists about whether food selection occurs according to native/introduced status or to species. We tested preference of the native herbivore white-tailed deer (Odocoileus virginianus) for widespread and frequently occurring invasive introduced and native plants in the northeastern United States. Multiple-choice deer preference trials were conducted for the species and relative preference was determined using biomass consumption and feeding behavior. While more native than introduced plant biomass was consumed overall, deer food selection varied strongly by plant species. Results show consistent deer avoidance of several invasive introduced plants (Alliaria petiolata, Berberis thunbergii, and Microstegium vimineum) and a native plant (Dennstaedtia punctilobula). Other invasive introduced plants (Celastrus orbiculatus, Ligustrum vulgare, and Lonicera morrowii) and a native plant (Acer rubrum) were highly preferred. These results provide evidence that herbivore impacts on plant invaders depend on plant species palatability. Consequently, herbivore selectivity likely plays an important role in the invasion process. To the extent that herbivory impacts population demographics, these results suggest that native generalist herbivores promote enemy release of some plant invaders by avoiding them and contribute to biotic resistance of others by consuming them.

Evaluating exotic plants as evolutionary traps for nesting Veeries

ABSTRACT Human-induced rapid environmental change, such as the introduction of exotic species, can create novel species interactions that might be detrimental to native organisms. For birds, introduced plant species may represent potentially attractive, but dangerous, locations to place a nest. If the environmental cues that birds use to select safe nest sites are unreliable when they apply to nonnative plant species, these plants could act as evolutionary traps: preferred nest substrates that confer the poorest reproductive outcomes. We tested this possibility by assessing reproductive consequences of nest substrate preference in the Veery (Catharus fuscescens). We followed the fates of nests in native plants and in three nonnative plants associated with reduced nest success in previous studies (Amur honeysuckle [Lonicera maackii], multiflora rose [Rosa multiflora], and Japanese barberry [Berberis thunbergii]). Veeries preferred to locate nests in nonnative plants and in denser patches of vegetation more...

Hnojiva s pozvolným uvolňováním a možnosti jejich využití ve školkařství

Reserve, slow-release fertilizers (SRF) enable to simplify the whole system of plant nutrition and fertilisation. Tabletted fertilizers of the Silvamix series represent a prospective product of Czech provenience. At our university, these fertilizers have been tested and used since the year 1991. Ornamental woody species grown in containers were investigated in two stages. Experiments with ornamental plants were established using one-year-old cuttings and seedlings of the following deciduous and evergreen woody species:Cotoneaster dammeri Skogholm,Berberis thunbergii,Potentilla fruticosa Snowflake,Ligustrum vulgare AtrovirensandPicea omorika. After planting into containers, fertilizers in the dose of 1 tablet (i.e. 10 g) per litre of substrate were applied either to roots level or on the soil surface in the container. Silvamix in the dose of 5 g.l-1was used as the tested fertilizer in the second stage. It was applied during the planting in the form of tablets and/or a powder. Control plants were fertilized in the course of growing season using a common agricultural fertilizer Cererit Z. The annual plants increments were measured. These experiments demonstrated a long-term optimum effect of this product on woody species and an equal quality and efficiency of its tabletted and powdered forms.

Historic Mining and Agriculture as Indicators of Occurrence and Abundance of Widespread Invasive Plant Species.

Anthropogenic disturbances often change ecological communities and provide opportunities for non-native species invasion. Understanding the impacts of disturbances on species invasion is therefore crucial for invasive species management. We used generalized linear mixed effects models to explore the influence of land-use history and distance to roads on the occurrence and abundance of two invasive plant species (Rosa multiflora and Berberis thunbergii) in a 900-ha deciduous forest in the eastern U.S.A., the Powdermill Nature Reserve. Although much of the reserve has been continuously forested since at least 1939, aerial photos revealed a variety of land-uses since then including agriculture, mining, logging, and development. By 2008, both R. multiflora and B. thunbergii were widespread throughout the reserve (occurring in 24% and 13% of 4417 10-m diameter regularly-placed vegetation plots, respectively) with occurrence and abundance of each varying significantly with land-use history. Rosa multiflora was more likely to occur in historically farmed, mined, logged or developed plots than in plots that remained forested, (log odds of 1.8 to 3.0); Berberis thunbergii was more likely to occur in plots with agricultural, mining, or logging history than in plots without disturbance (log odds of 1.4 to 2.1). Mining, logging, and agriculture increased the probability that R. multiflora had >10% cover while only past agriculture was related to cover of B. thunbergii. Proximity to roads was positively correlated with the occurrence of R. multiflora (a 0.26 increase in the log odds for every 1-m closer) but not B. thunbergii, and roads had no impact on the abundance of either species. Our results indicated that a wide variety of disturbances may aid the introduction of invasive species into new habitats, while high-impact disturbances such as agriculture and mining increase the likelihood of high abundance post-introduction.

Response of Japanese Barberry to Varying Degrees of Defoliation

Abstract Until recently, it was thought that Berberis thunbergii (Japanese Barberry), a non-native invasive plant that has become particularly widespread in certain regions of New Jersey, benefited from a lack of herbivorous defoliators. However, in 2007 extensive defoliation was documented across a wide geographical distribution in New Jersey, calling this assumption into question. We tested whether Japanese Barberry was negatively affected by partial defoliation by manually clipping 50% or 100% of leaves on current-year stems on small and large plants in the summer of 2008. We found almost no impact of defoliation on growth, carbon storage, or leaf-level physiology for either treatment. We noted some differences between large and small plants, but these were not related to defoliation treatments. Our results suggest that, even in the presence of herbivory, Japanese Barberry is capable of maintaining growth and carbon reserves, thus making it an effective competitor for resources.

Interactive effects of deer, earthworms and non-native plants on rare forest plant recruitment

Multiple biotic and abiotic factors, operating at several stages may affect plant demography and recruitment. Across forests in North America increased white-tailed deer (Odocoileus virginianus) abundance, non-native earthworms and non-native plant invasions are likely to generate single and interactive effects. We evaluated effects of these stressors on recruitment of three rare plants (Aristolochia serpentaria, Carex retroflexa and Trillium erectum). We conducted a multiple year seed addition experiment using paired open and fenced plots (experimentally excluding deer) at 12 forested sites that differ in earthworm density and non-native plant cover. We found strong microsite limitations for C. retroflexa, which completely failed to establish after a 3-year period despite successful germination in greenhouse trials. Addition of A. serpentaria and T. erectum seed resulted in successful seedling emergence; however, A. serpentaria recruitment steadily decreased over the study period. We found no significant effects of non-native Alliaria petiolata or Berberis thunbergii on seedling recruitment but surprisingly, we found strong positive effects of non-native Microstegium vimineum on A. serpentaria and T. erectum. Deer exclusion resulted in increased T. erectum emergence and seedling survival. Earthworm abundance negatively affected survival of T. erectum seedlings, and the effect manifested itself through interactive effects with fencing and non-native plants. Comparing recruitment through seeding addition to recruitment through transplants in a parallel study, we identified strong potential for T. erectum restoration using seed addition, but this will be dependent upon a significant reduction of deer impacts. Restoration of A. serpentaria and C. retroflexa will require manipulation of microsite conditions to promote recruitment.

Single and interactive effects of deer and earthworms on non-native plants

Understanding drivers of plant invasions is essential to predict and successfully manage invasions. Across forests in North America, increased white-tailed deer (Odocoileus virginianus) abundance and non-native earthworms may facilitate non-native plant invasions. While each agent may exert independent effects, earthworms and deer often co-occur and their combined effects are difficult to predict based solely on knowledge of their individual effects. Using a network of twelve forested sites that differ in earthworm density, we evaluated deer exclusion effects (30×30m; with an adjacent similar sized unfenced control plot) on cover, growth and reproduction of three non-native plant species: Alliaria petiolata, Berberis thunbergii and Microstegium vimineum. In addition, we assessed interactive effects of deer exclusion and earthworm invasions on B. thunbergii ring-growth. Five years after fence construction, A. petiolata frequency and density, B. thunbergii height, and M. vimineum cover were all significantly lower in fenced compared to open plots. In addition, B. thunbergii ring-growth was significantly lower in fenced compared to open plots, and ring-growth was positively correlated with earthworm density. Moreover, deer access and earthworm density synergistically interacted resulting in highest B. thunbergii ring-growth in open plots at sites with higher earthworm density. Results indicate facilitative effects of deer on non-native plant species and highlight the importance of understanding interactions among co-occurring factors in order to understand non-native species success. Successful long-term control of invasive plants may require a reduction in deer abundance, rather than just removing invasive plant species.

Suitability of Eight Northeastern U.S. Native Shrubs as Replacements for Invasive Plants in a Difficult Landscape Site with White-tailed Deer Pressure

Nursery and landscape professionals are interested in white-tailed deer (Odocoileus virginianus)–resistant native plants to replace invasive species used in difficult landscape sites, such as parking lot islands, which are dry, nutrient-poor, and exposed to sun and heat. Eight native shrubs [creeping sand cherry (Prunus pumila var. depressa), elderberry (Sambucus canadensis), gray dogwood (Cornus racemosa), highbush blueberry (Vaccinium corymbosum), round leaf dogwood (Cornus rugosa), northern spicebush (Lindera benzoin), sweetbells (Eubotrys racemosa), and virginia rose (Rosa virginiana)] were planted in a large commuter parking lot on the University of Connecticut campus to evaluate their suitability for use in difficult landscapes. The non-native, invasive shrubs ‘Compactus’ winged euonymus (Euonymus alatus) and ‘Crimson Pygmy’ japanese barberry (Berberis thunbergii) were also planted as controls representing non-native species typically planted in such sites. Aesthetic quality ratings for sweetbells matched the controls (rating of 4.5 out of 5.0) and plants exhibited a high level of white-tailed deer resistance. Virgina rose and creeping sand cherry had similar aesthetic quality to controls, despite light grazing of plants by white-tailed deer. Elderberry was damaged by moderate white-tailed deer grazing and snow load, but plants regenerated to 485% of initial size in one growing season with white-tailed deer exclusion. Gray dogwood, round leaf dogwood, and northern spicebush exhibited the least resistance to white-tailed deer grazing. Both dogwood species had lower aesthetic quality than the controls, and round leaf dogwood had the lowest survival rate (68%) after 2 years. However, several individuals of gray dogwood, round leaf dogwood, and northern spicebush that were less heavily damaged by white-tailed deer grew into attractive shrubs after white-tailed deer exclusion. Highbush blueberry had significantly lower aesthetic quality than controls and only 75% survival after 2 years, indicating that this species is an unsuitable replacement for invasives in difficult landscape sites. This study identified the underused native shrubs sweetbells, virginia rose, and creeping sand cherry as suitable replacements for invasives in difficult landscape sites with white-tailed deer pressure.

Citizen science contributes to our knowledge of invasive plant species distributions

Citizen science is commonly cited as an effective approach to expand the scale of invasive species data collection and monitoring. However, researchers often hesitate to use these data due to concerns over data quality. In light of recent research on the quality of data collected by volunteers, we aimed to demonstrate the extent to which citizen science data can increase sampling coverage, fill gaps in species distributions, and improve habitat suitability models compared to professionally generated data sets used in isolation. We combined data sets from professionals and volunteers for five invasive plant species (Alliaria petiolata, Berberis thunbergii, Cirsium palustre, Pastinaca sativa, Polygonum cuspidatum) in portions of Wisconsin. Volunteers sampled counties not sampled by professionals for three of the five species. Volunteers also added presence locations within counties not included in professional data sets, especially in southern portions of the state where professional monitoring activities had been minimal. Volunteers made a significant contribution to the known distribution, environmental gradients sampled, and the habitat suitability of P. cuspidatum. Models generated with professional data sets for the other four species performed reasonably well according to AUC values (>0.76). The addition of volunteer data did not greatly change model performance (AUC > 0.79) but did change the suitability surface generated by the models, making them more realistic. Our findings underscore the need to merge data from multiple sources to improve knowledge of current species distributions, and to predict their movement under present and future environmental conditions. The efficiency and success of these approaches require that monitoring efforts involve multiple stakeholders in continuous collaboration via established monitoring networks.

MNOŽENÍ BERBERIS THUNBERGII L. ŘÍZKY PŘI POUŽITÍ MÉNĚ ZNÁMÝCH ZPŮSOBŮ STIMULACE

The different type of own produce stimulators were tested at Berberis thunbergii L. 'Green Carpet', Berberis thunbergii 'Red Shift' and Berberis thunbergii 'Aureum'. We used the combination of growing inhibitors and quick-dip method, single quick-dip metod in solution of acetone and stimulant in form of gel. Groving inhibitors is including paclobutrazol and CCC in test. We used IBK, NAA, IAA and nicotin acid as auxins in quick-dip method. Medium was aceton solution.

Little impact of the invasive shrub Japanese barberry (Berberis thunbergiiDC) on forest understory plant communities1

As exotic species invasions continue to transform patterns of biological diversity, it becomes increasingly urgent to understand invasions' full consequences. Woody exotics that colonize closed-canopy forests have the potential for strong effects on plant communities. Berberis thunbergii DC, one such species, has invaded forests throughout eastern North America. Here we quantified the impacts of B. thunbergii invasions on the diversity and composition of native plant communities, both directly and through possible modifications of nutrient, moisture, and light availability. Plots with and without B. thunbergii had similar species richness, evenness, and diversity. Only two species were less likely to occur in plots with B. thunbergii. We also found no effect of B. thunbergii on soil moisture or other key soil properties such as pH and organic matter content. Plots with B. thunbergii had lower light levels at 10 cm from the ground, as under any shrub. It is possible that the invasion we observed may develop into a dense thicket with more severe impacts; however, the effects of B. thunbergii were modest at this time.

Biochemical changes in barberries during adventitious root formation: the role of indole-3-butyric acid and hydrogen peroxide

Peroxidase, polyphenol oxidase (PPO), phenolic compounds and total sugars (TS) were investigated during root formation in cuttings of Berberis vulgaris var. asperma (BVA) and Berberis thunbergii var. atropurpurea (BTA) treated with indole-3-butyric acid (IBA) and IBA+H2O2. Rooting was observed on BTA cuttings but not on BVA cuttings. The BTA cuttings treated with IBA and IBA+H2O2 showed higher rooting percentages, number of roots, and root length over the control. Those treated with IBA+H2O2 recorded the lowest peroxidase activity after planting. BTA cuttings treated with IBA+H2O2 showed the highest peroxidase activity at 50 d after planting; BVA cuttings under different treatments showed no significant difference for peroxidase activity at planting time or up to 80 d after planting. PPO activity for the BTA cuttings in the control treatment was lower than for other treatments during root formation. The cuttings in the IBA and IBA+H2O2 treatments showed increased PPO activity from 0 to 50 d after planting and a slight decrease in PPO activity from 60 to 80 d after planting. PPO activity for the BVA cuttings was significantly lower than for BTA during root formation. The BTA cuttings treated with IBA and IBA+H2O2 showed the highest phenolic compound content during root formation. The BVA cuttings displayed higher TS than BTA during the initial stage of root formation. A comparison of the anatomical structure of easy-to-root and difficult-to-root cuttings indicated that physical inhibitors did not affect the rooting capacity of BVA.

Comparing Effectiveness and Impacts of Japanese Barberry (Berberis thunbergii) Control Treatments and Herbivory on Plant Communities

AbstractTwo factors that can degrade native plant community composition and structure, and hinder restoration efforts, are invasive species and chronic overbrowsing by ungulates such as white-tailed deer. Beginning in 2007, the effectiveness, costs, and impacts of Japanese barberry control treatments and herbivory on nonnative and native plant communities was examined at eight study areas over 4 to 5 yr. Prescribed burning and mechanical mowing by wood shredder or brush saw were utilized as initial treatments to reduce the aboveground portion of established barberry and were equally effective. Without a follow-up treatment, barberry had recovered to 56 to 81% of pretreatment levels 50 to 62 mo after initial treatment. Follow-up treatments in mid-summer to kill new sprouts included directed heating and foliar herbicide applications. Relative to untreated controls, follow-up treatments lowered barberry cover 50 to 62 mo after initial treatment by at least 72%. Although all follow-up treatments were equally effective, the labor cost of directed heating was four times higher than for herbicide applications. Follow-up treatment type (directed heating vs. herbicide) had minimal impact on species other than barberry. White-tailed deer herbivory had a larger impact on other species than did barberry control treatments. Native grass and fern cover was higher outside of exclosures. Areas inside exclosures had higher cover of Oriental bittersweet and multiflora rose, but not Japanese barberry. Thus, recovery of native communities will require more than simply removing the dominant invasive species where deer densities are high. Excellent reduction of Japanese barberry cover can be achieved using either directed heating or herbicides as follow-up treatments in a two-step process, but other invasive plants may become a problem when barberry is removed if deer populations are low.

Mszyce z rodziny bawełnicowatych (Pemphigidae) w pojemnikowej uprawie roślin ozdobnych

Summary The following species of woolly aphids appeared in containers with coniferous shrubs: Gootiella tremulae on yews (Juniperus chinensis, J. horizontalis, J. × media and J. squamata), Prociphilus (Stagona) pini on pines (Pinus sylvestris and P. mugo) and Pachypappa vesicalis on Norway spruce (Picea abies). In container production of perennial plants, Colopha compressa was feeding on roots of sedges (Carex buchananii and C. morowii) and Thecabius (Parathecabius) lysimachiae on roots of golden creeping jenny (Lysimachia nummularia). In containers with deciduous shrubs such as Thunberg's barberry (Berberis thunbergii), smooth hydrangea (Hydrangea arborescens), weigela (Weigela florida), shrubby cinquefoil (Potentilla fruticosa), Japanese spiraea (Spiraea japonica) and Grefsheim spiraea (Spiraea × cinerea), the lettuce root aphid (Pemphigus bursarius) was found. However, this aphid was not inhibiting roots of deciduous shrubs, but was feeding on roots of common dandelion (Taraxum officinale) – common weed in container production.

Amplicon pyrosequencing reveals the soil microbial diversity associated with invasive Japanese barberry (Berberis thunbergii DC.)

The soil microbial community acts as a reservoir of microbes that directly influences the structure and composition of the aboveground plant community, promotes plant growth, increases stress tolerance and mediates local patterns of nutrient cycling. Direct interactions between plants and rhizosphere-dwelling microorganisms occur at, or near, the surface of the root. Upon introduction and establishment, invasive plants modify the soil microbial communities and soil biochemistry affecting bioremediation efforts and future plant communities. Here, we used tag-encoded FLX amplicon 454 pyrosequencing (TEFAP) to characterize the bacterial and fungal community diversity in the rhizosphere of Berberis thunbergii DC. (Japanese barberry) from invasive stands in coastal Maine to investigate effects of soil type, soil chemistry and surrounding plant cover on the soil microbial community structure. Acidobacteria, Actinobacteria, Proteobacteria and Verrucomicrobia were the dominant bacterial phyla, whereas fungal communities were comprised mostly of Ascomycota and Basidiomycota phyla members, including Agaricomycetes and Sordariomycetes. Bulk soil chemistry had more effect on the bacterial community structure than the fungal community. An effect of geographic location was apparent in the rhizosphere microbial communities, yet it was less significant than the effect of surrounding plant cover. These data demonstrate a high degree of spatial variation in the rhizosphere microbial communities of Japanese barberry with apparent effects of soil chemistry, location and canopy cover on the microbial community structure.