Crowberry Empetrum Nigrum Research Articles

How Do Nitrogen Deposition, Mowing, and Deer Grazing Drive Vegetation Changes on Dune Heaths?

Heathland vegetation has undergone significant changes in the past century, e.g., due to airborne pollutants and a lack of proper management. Understanding the interactions between these factors in combination is pivotal for heathland conservation. Here, we studied the vegetation changes at a dune heath in a four-year manipulation experiment analysing the combined effects of nitrogen deposition, mowing, and deer grazing. Our results showed no significant effect of nitrogen deposition and deer grazing on plant growth and cover of dwarf shrubs within the experimental plots. However, high loads of nitrogen decreased bryophyte cover and increased the growth and cover of sand sedge Carex arenaria L. Mowing adversely affected the dwarf shrub community, e.g., the dwarf shrub species crowberry Empetrum nigrum L., and facilitated increased cover and plant growth of graminoids. Plant growth and the cover of C. arenaria increased in plots without deer grazing, whereas bryophyte cover decreased significantly without grazing. We do not recommend intensive mowing of vegetation as a conservation method for dune heaths because it promotes graminoids. From a conservation aspect, it is essential to consider the effect of deer on heathlands because they both impede some species and benefit others and mitigate the adverse effects of nitrogen deposition on dune heaths.

Using high performance thin layer chromatography for the detection of pharmacologically active secondary metabolites in Empetrum nigrum L.

Introduction. The article presents the results of the detection of pharmacologically active secondary metabolites in black crowberry Empetrum nigrum L. using the method of high performance thin layer chromatography (HPTLC).Aim. To show the efficiency of HPTLC for conducting preliminary phytochemical analysis to determine the main groups of metabolites in promising medicinal plant species.Materials and methods. HPTLC analysis was carried out on a CAMAG device (Switzerland), using MERCK HPTLC silica gel 60 F154, 20 × 10 cm plates. For the evaporation of the samples, a Heidolph vacuum rotary evaporator (Germany) was used. The aerial parts (shoots) of Empetrum nigrum were harvested next to St. Petersburg State Chemical and Pharmaceutical University (SPCPU) nursery garden of medicinal plants (Leningrad Region, Vsevolozhsky District, Priozerskoe Highway, 38 km) in August 2019.Results and discussion. In the course of the research, four fractions from the aerial parts of Empetrum nigrum were obtained: hexane, dichloromethane, butanol, and water. Then, these fractions were investigated by HPTLC in two solvent systems – n-butanol : acetic acid : water (BAW) (4 : 1 : 2) and hexane : dichloromethane : methanol (HDM) (1 : 2 : 0.5). After scanning densitometric analysis of the plates eluted in the HDM system, it was revealed, that the hexane and dichloromethane fractions have a similar composition and contain the greatest amount of compounds, compared to the butanol and water fractions, and in the BAW system, it was found, that the butanol fraction contains the greatest variety of metabolites. As a result of UV spectroscopy, it was found, that the main groups of compounds contained in the hexane and dichloromethane fractions are derivatives of chalcones, dihydrochalcones, bibenzyls and 9,10-dihydrophenanthrenes. While in the butanol fraction, the main groups of secondary metabolites were derivatives of flavonoids and tanninsConclusion. The data obtained allow us to note the efficiency, speed and simplicity of HPTLC for conducting preliminary phytochemical analysis to determine the main groups of metabolites of promising medicinal plant species.

Host species shape the community structure of culturable endophytes in fruits of wild berry species (Vaccinium myrtillus L., Empetrum nigrum L. and Vaccinium vitis-idaea L.).

ABSTRACTWild berries are interesting research subjects due to their rich sources of health-beneficial phenolic compounds. However, the internal microbial communities, endophytes, associated with the wild berry fruits are currently unknown. Endophytes are bacteria or fungi inhabiting inside plant tissues, and their functions vary depending on the host species and environmental parameters. The present study aimed to examine community composition of fungal and bacterial endophytes in fruits of three wild berry species (bilberry Vaccinium myrtillus L., lingonberry Vaccinium vitis-idaea L. and crowberry Empetrum nigrum L.) and the effects of host plant species and their growth sites on shaping the endophytic communities. We found that the endophytic community structures differed between the berry species, and fungi were predominant over bacteria in the total endophytic taxa. We identified previously unknown endophytic fungal taxa including Angustimassarina, Dothidea, Fellozyma, Pseudohyphozyma, Hannaella coprosmae and Oberwinklerozyma straminea. A role of soluble phenolic compounds, the intracellular components in wild berry fruits, in shaping the endophytic communities is proposed. Overall, our study demonstrates that each berry species harbors a unique endophytic community of microbes.

An ericoid shrub plays a dual role in recruiting both pines and their fungal symbionts along primary succession gradients

Relative importance of positive and negative interactions between plant species may change along disturbance and resource gradients. Positive interactions are suggested to prevail in low resource, low productivity (high stress) conditions and negative interactions in high resource availability. A dwarf shrub, mountain crowberry Empetrum nigrum ssp. hermaphroditum, is known to have allelopathic impacts on both Scots pine Pinus sylvestris and its ectomycorrhizal symbionts. We aimed to study if the outcome of Empetrum impacts on Scots pine changes along primary succession gradients on the dune shores of Bothnian Bay, in Finland, where abiotic stress gradually changes to biotic stress along the succession. We found that Empetrum may act as a facilitator despite its allelopathic effects, since the proportion of Scots pine seedlings established in Empetrum patches was higher than in patches without the shrub in early and mid succession stages, whereas patches without Empetrum were preferred in late succession. The amount of mycelial fungal biomass (ergosterol) in the soil in the vicinity of the seedling roots was higher in Empetrum patches than in patches without Empetrum and it increased along the succession gradient. Proportion of pine root tips colonised by suilloid morphotypes with abundant external mycelia and the diversity of ectomycorrhizal morphotypes were higher in mid successional stage in Empetrum patches compared to patches without Empetrum. Our results suggest that in the harsh physical conditions of the dune shore Empetrum facilitates pine seedling establishment in the early and mid stages of succession by providing mechanical and physical shelter whereas in late succession negative interactions (competition and allelopathy) between the shrub and the pine are dominating. To our knowledge we present the first finding that an ericoid mycorrhizal shrub could enhance both the performance of the ectomycorrhizal host tree and the tree's fungal symbionts.

Antioxidant Capacity and Quercetin Levels in Alaska Wild Berries

Alaska wild berries were harvested in 2003 to evaluate levels of antioxidants in non-cultivated fruit. Berries were stored frozen for up to 20 months until analysis for levels of quercetin and hydrophilic oxygen radical absorbance capacity (H-ORACFL). H-ORACFL levels were highest in lingonberry Vaccinium vitis-idaea L.(119-320, average 203 µmol of Trolox Equivalents (TE)/g fresh weight (FW), n = 13). H-ORACFL levels in other berries from interior Alaska averaged 174 µmol TE/g for highbush cranberry Viburnum edule (Michx.) Raf., 107µmol of TE/g for crowberry Empetrum nigrum L., and 77 µmol of TE/g for bog blueberry Vaccinium uliginosum L. Quercetin levels ranged from 0.5 to 14.6 µg/g FW in these 4 species from interior Alaska. Lingonberry and bog blueberry had higher levels of quercetin than most other berries tested. Alaskan wild berries are rich sources of antioxidants.

Habitat selection, diet, arthropod availability and growth of a moorland wader: the ecology of European Golden Plover Pluvialis apricaria chicks

Habitat use, diet and food supply of European Golden Plover Pluvialis apricaria chicks were studied on blanket bog in the South Pennines, UK. The home ranges occupied by chicks until fledging averaged 40 ha; they contained relatively more cotton grass and bare peat than was available generally, but less heather and grassland. Use of Bilberry Vaccinium myrtillus and Crowberry Empetrum nigrum increased with age, whereas that of cotton grass Eriophorum spp. declined. Dietary composition, as assessed by faecal analysis, was similar to that obtained from the crops of dead birds. The diet of younger chicks, assessed by dry weight of prey, consisted of about 30% each of adult and larval tipulids, whereas for chicks older than 16 days, about 70% was tipulid larvae. Beetles, spiders and caterpillars each comprised 5–20% of the diet, depending on age. Older chicks took larger prey. The exploitation of larval tipulids was correlated positively with the chicks’ use of cotton grass and bare peat areas, whereas caterpillars, beetles and spiders were more often taken from dwarf shrubs, reflecting variation in prey abundance. Bare peat was an important foraging habitat, whose exploitation was associated positively with the growth rate of young chicks, and with mean prey size. Both weight gain and survival of young chicks were positively correlated with the abundance of tipulid adults, confirming the hypothesis that the flush of tipulid hatching is an important determinant of breeding success. Golden Plover chicks are capable of considerable movements to track variation in prey availability. This behaviour is likely to be an important survival strategy facilitating the utilization of a mosaic of cotton grass and dwarf shrub habitats. Appropriate rotational strip‐burning or grazing management could be used to create and maintain such habitats.

The diet of brown bears Ursus arctos in central Scandinavia: effect of access to free‐ranging domestic sheep Ovis aries

The seasonal food habits of brown bears Ursus arctos were estimated based on the analysis of 266 scats in central Norway and Sweden. Free‐ranging domestic sheep Ovis aries were common in the Norwegian part of the study area, but were not found in the Swedish part. Correction factors were used to correct for differences in digestibility and nutritional value of different foods. Because correction factors for ungulates are difficult to estimate, the results should be interpreted with some caution. In terms of digestible energy, ungulates, mostly carrion, were the most important food in both areas during spring. During summer, ants, forbs, and ungulates (reindeer Rangifer tarandus and moose Alces alces) were the most important food items in the Swedish area, and sheep were most important in the Norwegian area. The autumn diet was dominated by berries in the Swedish area and sheep and berries in the Norwegian area. Among berries, crowberry Empetrum nigrum was the most important species, followed by bilberry Vaccinium myrtiUus in Sweden. The major difference between the Swedish and Norwegian areas was the large consumption of sheep in Norway, which provided protein and lipids, and was associated with a relatively reduced consumption of ants and forbs in summer and berries in the autumn. Based on different ingestion rates among the seasons, we estimated the relative contribution of major foods to total digestible energy. In the Swedish area, bears obtained 44–46 and 14–30% of their total annual energy from berries and ungulates, respectively. The remaining energy was obtained from insects (14–22%, mostly ants) and forbs and graminoids (12–18%, mostly blue sow thistle Cicerbita alpina). In Norway, bears obtained 65–87% of the energy from ungulates (mostly sheep), 6–17% from berries, 5–13% from insects, and 2–6% from forbs and graminoids. To gain weight prior to denning, brown bears in Norway selected lipid‐rich and easily obtainable sheep in summer and autumn. In Sweden, they relied on carbohydrate‐rich berries in autumn.

Response of bilberry Vaccinium myrtillus L. stands in the Derbyshire Peak District to sheep grazing, and implications for moorland conservation

Exclosure systems were set up at two sites in Derbyshire, England, in 1990 to compare summer, winter, year-round and zero grazing. Initially the sites were similar in bilberry Vaccinium myrtillus extent, with cover means c. 70%, but they differed in heather Calluna vulgaris extent, with cover means 1 and 25%. Sheep occupance was estimated from counts of faecal-pellet groups six or seven times a year and utilisation of bilberry and heather from assessments in permanent positions four times a year. Plant cover was measured each August from 1990 to 1996. It was found that the sheep consistently chose to graze the bilberry swards much more heavily in autumn than the rest of the year. Dung deposition rates were quite similar at the two sites, but the winter-only grazed plots had significantly greater dung deposition at the heather-bilberry site than the pure bilberry site. Shoot utilisation reflected sheep occupance. Winter protection reduced utilisation, significantly so at the pure bilberry site, but differences were minimised because of bursts of heavy usage following the reopening of the plots to grazing in April. At the pure bilberry site the height of bilberry stayed remarkably constant under all three grazing regimes, but increased sharply in the absence of grazing. Bilberry cover was unaffected by season of grazing, but crowberry Empetrum nigrum appeared to benefit from winter protection. At the heather-bilberry site, bilberry was significantly reduced in cover under all the grazing treatments, whereas heather increased significantly in cover and height despite an average grazing pressure of 1·4 sheep ha −1. This suggests that the desired light stocking rates presently being advocated to conserve heather moorland will cause losses of bilberry moorland, and that for the conservation of a diversity of vegetation types in a block of moorland some zonal variation in grazing pressure is required.