Vaccinium Uliginosum Research Articles

Structural changes of potato starch and activity inhibition of starch digestive enzymes by anthocyanin from lingonberry (Vaccinium uliginosum L.) retarded starch digestibility

The effects of anthocyanins on in vitro and in vivo digestibility of potato starch were evaluated in this study. Then the influence of anthocyanins on physicochemical property of potato starch and the activity of starch digestive enzymes (α-amylase and α-glucosidase) were also investigated to understand the mechanism of anthocyanins on starch digestibility. Results have shown that dietary anthocyanins could effectively inhibit the biological activities of α-amylase and α-glucosidase to delay the peak of postprandial blood glucose. Characterization of physicochemical properties of potato starch indicates a structural change due to the presence of anthocyanins, hindering its access to starch digestive enzymes. Among all anthocyanins, lingonberry anthocyanin significantly promoted the retrogradation of potato starch (7.153 % to 25.913 %) and exert promising inhibition on α-amylase and α-glucosidase. Lingonberry anthocyanins mainly interacted with potato starch through hydrogen bonds, which reduce the amount of amylose molecules leached from potato starch and loosen the three-dimensional (3D) network structure of starch gel. This study could provide theoretical evidence for utilization of anthocyanins in diabetic-management function food.

Identification and Analysis of Phenolic Compounds in Vaccinium uliginosum L. and Its Lipid-Lowering Activity In Vitro.

Vaccinium uliginosum L. (VU), rich in polyphenols, is an important wild berry resource primarily distributed in extremely cold regions. However, the detailed composition of Vaccinium uliginosum L. polyphenols (VUPs) has not been reported, which limits the development and utilization of VU. In this study, VU-free polyphenols (VUFPs) and VU-bound polyphenols (VUBPs) were, respectively, extracted using an ultrasonic, complex enzyme and alkali extraction method; the compositions were identified using ultra-performance liquid chromatography-electrospray ionization mass spectrometry, and lipid-lowering activity in vitro was evaluated. The results showed that 885 polyphenols and 47 anthocyanins were detected in the VUFPs and VUBPs, and 30 anthocyanin monomers were firstly detected in VU. Compared with the model group, the accumulation of lipid droplets and the total cholesterol and triglyceride contents in the high-concentration VUP group reduced by 36.95%, 65.82%, and 62.43%, respectively, and liver damage was also alleviated. It was also found that VUP can regulate the level of Asialoglycoprotein receptor 1, a new target for lipid lowering. In summary, this study provides a detailed report on VUP for the first time, confirming that VUP has lipid-lowering potential in vitro. These findings suggest new strategies and theoretical support for the development and utilization of VU, especially in the field of functional foods.

Nutrient responses of vascular plants to N2-fixing tree Alnus hirsuta encroachment in a boreal peatland.

The N2-fixing trees Alnus spp. have been widely encroaching into boreal peatlands, but the nutrient responses of native vascular plants remain unclear. Here, we compared nutrient concentrations and isotope signal of six common plants (Betula fruticosa, Salix rosmarinifolia, Vaccinium uliginosum, Rhododendron tomentosum, Chamaedaphne calyculata, and Eriophorum vaginatum) between Alnus hirsuta island and open peatland and assessed plant nutrient responses to A. hirsuta encroachment in boreal peatlands. Alnus hirsuta encroachment increased nitrogen (N) concentration of leaf, branch, and stem. Despite no significant interspecific difference in branch and stem, the increment magnitude of leaf N concentration varied among species, with greatest magnitude for R. tomentosum (55.1% ± 40.7%) and lowest for E. vaginatum (9.80% ± 4.40%) and B. fruticosa (18.4% ± 10.7%). Except for E. vaginatum, the significant increase in δ15N occurred for all organs of shrubs, with interspecific differences in change of leaf δ15N. According to the mass balance equation involving leaf δ15N, R. tomentosum and E. vaginatum, respectively, obtained highest (40.5% ± 19.8%) and lowest proportions (-14.0% ± 30.5%) of N from A. hirsuta. Moreover, the increment magnitudes of leaf N concentration showed a positive linear relationship with the proportion of N from A. hirsuta. In addition, A. hirsuta encroachment reduced leaf phosphorus (P) concentration of deciduous shrubs (i.e., B. fruticosa, S. rosmarinifolia, and V. uliginosum), thus increasing N:P ratio. These findings indicate that Alnus encroachment improves native plant N status and selectively intensifies P limitation of native deciduous shrubs, and highlight that the N acquisition from the symbiotic N2-fixing system regulates plant N responses in boreal peatlands.

Mapping Characteristics in Vaccinium uliginosum Populations Predicted Using Filtered Machine Learning Modeling

Bog bilberry (Vaccinium uliginosum L.) is considered a highly valued non-wood forest product (NWFP) species with edible and medicinal uses in East Asia. It grows in the northeastern forests of China, where stand attributes and structure jointly determine its population characteristics and individuals’ growth. Mapping the regional distributions of its population characteristics can be beneficial in the management of its natural resources, and this mapping should be predicted using machine learning modeling to obtain accurate results. In this study, a total of 60 stands were randomly chosen and screened to investigate natural bog bilberry populations in the eastern mountains of Heilongjiang and Jilin provinces in northeastern China. Individual height, canopy cover area, and fresh weight all increased in stands at higher latitudes, and shoot height was also higher in the eastern stands. The rootstock grove density showed a polynomial quadratic distribution pattern along increasing topographical gradients, resulting in a minimum density of 0.43–0.52 groves m−2 in stands in the southern part (44.3016° N, 129.4558° E) of Heilongjiang. Multivariate linear regression indicated that the bog bilberry density was depressed by host forest tree species diversity; this was assessed using both the Simpson and Shannon–Wiener indices, which also showed polynomial quadratic distribution patterns (with a modeling minimum of 0.27 and a maximum of 1.21, respectively) in response to the increase in latitude. Structural equation models identified positive contributions of tree diameter at breast height and latitude to shoot height and a negative contribution of longitude to the bog bilberry canopy area. Random forest modeling indicated that dense populations with heavy individuals were distributed in eastern Heilongjiang, and large-canopy individuals were distributed in Mudanjiang and Tonghua. In conclusion, bog bilberry populations showed better attributes in northeastern stands where host forest trees had low species diversity, but the dominant species had strong trunks.

The biochemical composition of wild berries and fruits growing in the Southwestern Taimyr

This article presents research findings on the chemical composition of fruits and berries found in the Southwestern Taimyr region, including bilberry (Vaccinium myrtíllus), northern redcurrant (Ribes triste), blueberry (Vaccinium uliginosum), prickly wild rose (Rosa acicularis), lingonberry (Vaccinium vitis-idaea), almost-holarctic crowberry (Empetrum subholarcticum), Siberian rowan (Sorbus sibirica), and cloudberry (Rubus chamaemorus). We revealed that rowan, blueberries, and prickly wild rose are particularly rich in crude fat. Additionally, prickly wild rose, and red currants were found to be high in crude fiber content, while bilberries, red currants, and cloudberries were dominant in crude protein. Potassium and calcium content were highest in prickly wild rose and rowan, while bilberries, red currants, and prickly wild rose had high sodium content. Moreover, crowberries and rowan berries were rich in phosphorus, and lingonberries, rowan berries, bilberries, and cloudberries were abundant in magnesium. Red currants, bilberries, and cloudberries had the highest total amino acid content, with essential amino acids being more prevalent than non-essential ones in redcurrant, bilberry, crowberry, and cloudberry samples. The content included high levels of leucine, isoleucine, valine, and threonine. Overall, the fruits and berries in the Southwestern Taimyr region have significant biological value and could be effectively used in creating functional biologically active substances.

First report of Fusarium commune Causing Bulb Rot on Lily (Lilium brownii var. Viridulum Baker) in Hunan Province of China.

Lily (Lilium brownii var. Viridulum Baker) is a well-known edible plant with large, white and sweet bulb scales that has important medicinal value (Zhou et al. 2021) and is grown mainly in the Hebei, Shanxi and Henan provinces of China. In May 2021, a case of bulb rot was discovered in a 3.33 hm2 plantation in Huaihua, Hunan Province, affecting 20% of the area (27°59'30″N, 110°32'20″E). The disease is most severe during the rainy season in May and June. In the early stage, irregular brown spots appeared on the lily scales, the necrosis was depressed and gradually enlarges, and in the later stage, the scales were scattered from the base of the disc and slough off. Ten samples were taken randomly from different plants in the plantation area to isolate the pathogens. After washing with sterile water, they were cut into small pieces and sterilised with 3% hydrogen peroxide for 30 s, 75% ethanol for 90 s, rinsed three times with sterile water and dried on sterile filter paper, then placed on a water agar plate and incubated in the dark in a constant temperature incubator at 28℃ for 3 to 5 days. After 2 days, the mycelium at the edge of the colony was transferred to a PDA plate and incubated for 3-5 days at 28°C in the dark to obtain pure fungal isolates. Eighteen purified fungal isolates were obtained, of which sixteen looked like Fusarium (88.9% isolation rate) and three representative isolates (BHBR2, BHBR3 and BHBR5) were selected for further study. The surface of this fungus was white with dense aerial mycelium. Some had an orange centre in the medium. Microconidia were oval in shape and appeared either straight or slightly curved. These microconidia were colourless, had 0-1 septa and measured 3.334 to 14.724 × 2.216 to 5.385 μm (n=100). Macroconidia were predominantly three-septate, crescent-shaped structures that were thin-walled and slightly curved. Cells at the apex and base were similarly curved. Macroconidia measured 17.956 to 32.150 × 2.788 to 4.492 μm (n=100). The mitochondrial small subunit (mtSSU) and translation elongation factor 1-α (TEF1) genes were amplified and sequenced using the NMS1/NMS2 and TEF-R/TEF-F primers to verify the identity of the pathogens (Stewart et al. 2006). The sequences were submitted to GenBank (BHBR2: mtSSU, PP273435; TEF, OR900976; BHBR3: mtSSU, PP277729; TEF, OR900977; BHBR5: mtSSU, PP277728; TEF, OR900978). A concatenated phylogenetic tree of the two genes was constructed and analysis showed that BHBR2, BHBR3 and BHBR5 were significantly clustered with Fusarium commune. Based on the results of morphological identification and phylogenetic tree analysis, the three isolates were identified as Fusarium commune. We carried out pathogenicity tests using two methods, one in which 6 × 6 mm fungal blocks were inoculated on lily (L. brownie var. viridulum Baker) scales and controls inoculated with sterile blocks, and the other in which strain BHBR2 was selected to carry out pathogenicity tests on bulbs of live plants soaked with 50 ml of a 1 × 106 conidial suspension and bulbs of control plants soaked with sterile water, all in three replicates. They were placed in a growth chamber at 28°C and 80% relative humidity, and the scales were moistened with moistened sterile filter paper. After 3 days of rearing treated scales, lesions appeared on lily scales inoculated with mycelial blocks and expanded with time, whereas no lesions appeared on lily scales inoculated with sterile blocks. One month later, whole plants soaked in the spore suspension wilted, while the control plants grew well. The pathogens re-isolated from the diseased tissues had the same morphological characteristics as representative isolates. This confirms Koch's hypothesis. Fusarium commune has been shown to be the most important pathogenic fungus causing root rot in Alfalfa (Medicago sativa) (Yang et al. 2022) and blueberry (Vaccinium uliginosum L.) (Li et al. 2023) in China. To our knowledge, this is the first report of Fusarium commune causing lily bulb rot in the world, which will lay the foundation for future control of lily bulb rot.

Adaptation of dwarf shrubs to Arctic tundra conditions in West Svalbard

The stability of the biota in the Arctic regions under climate change and increasing anthropogenic burdens is influenced by the adaptive potential of its representatives. This study aimed to assess the adaptive potential of dwarf shrubs (Betula nana, Vaccinium uliginosum, and Salix polaris) in the flora of West Svalbard on the basis of their morphological and anatomical features and total leaf lipid fatty acid content. All species have similar leaf anatomy characteristics: small leaves, dorsoventral structure with clear differentiation into palisade and spongy mesophyll, which ensures their growth in the Arctic. However, S. polaris is characterized by high volumes of the stomatal apparatus, an amphistomatic type of leaf, a high palisade coefficient, a large volume of mechanical leaf tissue, and a high content of unsaturated fatty acids (UFA). These features provide high functional activity, passage through all stages of ontogenesis, and a wide distribution of the species in West Svalbard. In contrast to S. polaris, B. nana and V. uliginosum are characterized by a decrease in leaf area, a decrease in the palisade coefficient, and a hypostomatic leaf type, which, combined with an increase in the diversity of “secondary” UFA, as well as the lack of generative development, may indicate a higher level pressure of extreme conditions for the species. Thus, these features may explain their limited representation in the ecotopes of West Svalbard. In contrast to B. nana and V. uliginosum, the higher adaptive potential of S. polaris ensures its greater stability in conditions of changing habitat. All studied dwarf shrub species can be used as markers for monitoring the environment in the high Arctic.

Effects of short- and long-term experimental warming on plant–pollinator interactions and floral rewards in the Low Arctic

Plant phenological and growth responses to experimental warming are widely documented, but less is known about warming effects on plant–pollinator interactions. We investigated the effects of short- and long-term passive warming on flowering phenology, insect visitation, fruit production, and floral rewards in the Low Arctic in northern Alaska. To better understand the role of insect visitors in plant reproductive success, we quantified pollen loads on floral visitors and tested for pollen limitation in four species. Long-term warming advanced flowering onset in evergreen shrubs and forbs. Warming, in general, increased the duration of flowering for forbs, evergreen shrubs, and deciduous shrubs. Considering all growth forms together, long-term warming increased floral density. This pattern was primarily driven by deciduous and evergreen shrubs. Dipterans accounted for more visits than Hymenopterans, although Hymenopterans had higher pollen loads. Insect exclusion and warming decreased fruit set in the forb, Bistorta officinalis Delarbre. Nectar volume in the deciduous shrub, Vaccinium uliginosum, was higher in the warmed plots than the control, but nectar quality did not differ. Advanced flowering onset, longer flowering duration, and increased flower density and nectar volume may have important implications for the pollinator community, warranting further research on long-term warming effects on tundra ecosystems.

Study on Morphological Traits of Natural Populations of Vaccinium uliginosum at Different Altitudinal Gradients on Changbai Mountain

Vaccinium uliginosum (VU) is one of the most precious wild berry plants distributed in the Changbai Mountain region in northeast China. Eight key morphological traits of VU were analyzed to examine the variation among and within five natural populations at different altitudes, as well as their response to environmental factors. The study results showed an increasing trend of variation among populations with ascending altitudes, but the range variation within populations exhibited a decreasing trend. The diversity level among populations was found to be higher than that within populations, and the five populations of VU were classified into four groups. Except for leaf width and twig length, all other morphological traits demonstrated significant or extremely significant correlations. Generally, with increasing altitude, leaf length decreased, while plant height, clear bole height, and basal diameter decreased significantly, and similar trends were observed with moisture factors, while a significant positive correlation was found with temperature factors. Among them, the morphological traits of clear bole height and basal diameter exhibited the strongest correlation with environmental factor variations. Overall, these findings indicate extensive variation in the morphological traits of VU within and among populations at different altitudes, with clear responses to changes in environmental factors.

Vaccinium uliginosum L. (bog bilberry) and the search for its alleged toxicity: a review.

Bog bilberry (Vaccinium uliginosum L.) is a wild-growing berry native to all circumboreal regions. There is however a significant discrepancy in the uses of bog bilberry fruits around the world. There exists a strong prejudice against the use of these berries in many European countries as well as a few incidences of poisoning reported between 1906 and 1944. In Asia and North America, this fear is completely absent from the local knowledge and the bog bilberry is valued as an excellent food and medicinal plant. There has been a lack of research on the topic in the last 50years and thus the presumed toxicity remains unproven. This review aims to gather the conflicting information from all regions where bog bilberry grows and present them in a critical way to elucidate the possible explanations for the discrepancies. There are several possible explanations for the alleged toxicity of the bog bilberry, including a fungal infection of the fruits, individual intolerance or accidental poisoning by a different plant species; the local names meaning "drunk, inebriating, vomit-inducing berry" may be related to the alcoholic drinks made from them. This review highlights the gap in knowledge and serves as a theoretical framework for future research.

Characterization of the Chemical Composition and Biological Activities of Bog Bilberry (Vaccinium uliginosum L.) Leaf Extracts Obtained via Various Extraction Techniques.

This investigation aimed to assess the chemical composition and biological activities of bog bilberry (Vaccinium uliginosum L.) leaves. Hydroethanolic extracts were obtained using four extraction techniques: one conventional (CE) and three alternative methods; ultrasound (UAE), microwave (MAE) and high-pressure (HPE) extractions. Spectrophotometric analysis was conducted to determine their chemical content, including the total phenolic content (TPC) and total flavonoid content (TFC). Furthermore, their antioxidative and antimicrobial properties were evaluated. HPLC (high performance liquid chromatography) analysis identified and quantified 17 phenolic compounds, with chlorogenic acid being the predominant compound, with the lowest level (37.36 ± 0.06 mg/g) for the bog bilberry leaf extract obtained by CE and the highest levels (e.g., HPE = 44.47 ± 0.08 mg/g) for the bog bilberry leaf extracts obtained by the alternative methods. Extracts obtained by HPE, UAE and MAE presented TPC values (135.75 ± 2.86 mg GAE/g; 130.52 ± 1.99 mg GAE/g; 119.23 ± 1.79 mg GAE/g) higher than those obtained by the CE method (113.07 ± 0.98 mg GAE/g). Regarding the TFC values, similar to TPC, the highest levels were registered in the extracts obtained by alternative methods (HPE = 43.16 ± 0.12 mg QE/g; MAE = 39.79 ± 0.41 mg QE/g and UAE = 33.89 ± 0.35 mg QE/g), while the CE extract registered the lowest level, 31.47 ± 0.28 mg QE/g. In the case of DPPH (1,1-diphenyl-2-picrylhydrazyl) antioxidant activity, the extracts from HPE, UAE and MAE exhibited the strongest radical scavenging capacities of 71.14%, 63.13% and 60.84%, respectively, whereas the CE extract registered only 55.37%. According to Microbiology Reader LogPhase 600 (BioTek), a common MIC value of 8.88 mg/mL was registered for all types of extracts against Staphylococcus aureus (Gram-positive bacteria) and Salmonella enterica (Gram-negative bacteria). Moreover, the alternative extraction methods (UAE, HPE) effectively inhibited the growth of Candida parapsilosis, in comparison to the lack of inhibition from the CE method. This study provides valuable insights into bog bilberry leaf extracts, reporting a comprehensive evaluation of their chemical composition and associated biological activities, with alternative extraction methods presenting greater potential for the recovery of phenolic compounds with increased biological activities than the conventional method.

Multiplexing PCR allows the identification of within-species genetic diversity in ancient eDNA.

Sedimentary ancient DNA (sedaDNA) has rarely been used to obtain population-level data due to either a lack of taxonomic resolution for the molecular method used, limitations in the reference material or inefficient methods. Here, we present the potential of multiplexing different PCR primers to retrieve population-level genetic data from sedaDNA samples. Vaccinium uliginosum (Ericaceae) is a widespread species with a circumpolar distribution and three lineages in present-day populations. We searched 18 plastid genomes for intraspecific variable regions and developed 61 primer sets to target these. Initial multiplex PCR testing resulted in a final set of 38 primer sets. These primer sets were used to analyse 20 lake sedaDNA samples (11,200 cal. yr BP to present) from five different localities in northern Norway, the Alps and the Polar Urals. All known V. uliginosum lineages in these regions and all primer sets could be recovered from the sedaDNA data. For each sample on average 28.1 primer sets, representing 34.15 sequence variants, were recovered. All sediment samples were dominated by a single lineage, except three Alpine samples which had co-occurrence of two different lineages. Furthermore, lineage turnover was observed in the Alps and northern Norway, suggesting that present-day phylogeographical studies may overlook past genetic patterns. Multiplexing primer is a promising tool for generating population-level genetic information from sedaDNA. The relatively simple method, combined with high sensitivity, provides a scalable method which will allow researchers to track populations through time and space using environmental DNA.

Vascular plants and mosses as bioindicators of variability of the coastal pine forest (Empetro nigri-Pinetum)

Empetro nigri-Pinetum is a unique sea coast plant community developing along the Baltic Sea from Germany to Lithuania. Our detailed field research of bryophytes and vascular plants has highlighted the regional diversity of the Empetro nigri-Pinetum typicum plant community throughout its range in Central Europe. Our study indicated that vascular plants and mosses effectively discriminate against the described phytocoenoses, thus it was possible to distinguish three variants of the coastal forest: Calluna–Deschampsia (from Germany), Vaccinium vitis–idaea (from Poland) and Melampyrum–Deschampsia (from Lithuania). Redundancy analysis indicated that the division is related to the habitat conditions of the analyzed areas, with humidity having the greatest impact on this differentiation. Kohonen’s artificial neural network (i.e. self-organising map, SOM) confirmed the heterogeneous nature of the studied phytocenoses, and combined with the IndVal index enabled identification of indicator species for respective studied patches: Deschampsia flexuosa for Calluna–Deschampsia group; Aulacomnium palustre, Calluna vulgaris, Carex nigra, Dicranum polysetum, Erica tetralix, Oxycoccus palustris, Sphagnum capillifolium, Vaccinium uliginosum and Vaccinium vitis–idaea for Vaccinium vitis–idaea group; and young specimens of Betula pendula, Lycopodium annotinum, Melampyrum pratense and Orthilia secunda for Melampyrum–Deschampsia group. Thereby, our study showed that individual groups of species can be very good bioindicators for each of the studied phytocoenoses.

Adaptability of introduced varieties of blueberry (Vaccinium Uliginosum L.) plant to climate conditions of Tashkent Province, Uzbekistan

Adaptability of introduced varieties of blueberry (<i>Vaccinium Uliginosum</i> L.) plant to climate conditions of Tashkent Province, Uzbekistan

Soil nutrient content dominates short-term vegetation changes in alpine tundra of Changbai Mountains.

Alpine tundra, covering 3% of the Earth's land surface, harbors approximately 4% of higher plant species. Changes in this vegetation significantly impact biodiversity and ecosystem services. Recent studies have primarily focused on large-scale and long-term vegetation changes in polar and high-latitude regions. However, the study of short-term vegetation changes and their primary drivers has received insufficient attention in alpine tundra. This study aimed to investigate vegetation changes and their dominant drivers in the alpine tundra of Changbai Mountains-located at the southern edge of the alpine tundra distribution in Eastern Eurasia-over a short period by re-surveying permanent plots in 2019 and comparing them with data from 2014. The results showed that significant changes were observed in alpine tundra vegetation during the study period. The importance values of typical alpine tundra plants such as Rhododendron chrysanthum, Vaccinium uliginosum, and Dryas octopetala decreased noticeably, while those of herbaceous species such as Deyeuxia angustifolia and Sanguisorba sitchensis increased significantly. Species richness, diversity, and evenness at different altitudinal gradients showed varying degrees of increase. A distinct expansion trend of herbaceous species was observed in the alpine tundra, contributing to a shift in plant community composition toward herbaceous dominance. This shift might result in the meadowization of the dwarf shrub tundra. Our findings further revealed that soil nutrients rather than climate factors, dominated the changes of plant communities over a short period. These findings provide scientific references for the conservation and management of biodiversity, as well as for projecting future vegetation dynamics in alpine tundra.

Vaccinium uliginosum and Vaccinium myrtillus-Two Species-One Used as a Functional Food.

Vaccinium uliginosum L. (commonly known as bog bilberry) and Vaccinium myrtillus L. (commonly known as bilberry) are species of the genus Vaccinium (family Ericaceae). The red-purple-blue coloration of blueberries is attributed largely to the anthocyanins found in bilberries. Anthocyanins, known for their potent biological activity as antioxidants, have a significant involvement in the prophylaxis of cancer or other diseases, including those of metabolic origin. Bilberry is the most important economically wild berry in Northern Europe, and it is also extensively used in juice and food production. A review of the latest literature was performed to assess the composition and biological activity of V. uliginosum and V. myrtillus. Clinical studies confirm the benefits of V. uliginosum and V. myrtillus supplementation as part of a healthy diet. Because of their antioxidant, anti-inflammatory, anti-cancer, and apoptosis-reducing activity, both bog bilberries and bilberries can be used interchangeably as a dietary supplement with anti-free radical actions in the prevention of cancer diseases and cataracts, or as a component of sunscreen preparations.

Characteristics of Microbial Abundance in Rhizosphere and Non-Rhizosphere Soils of Permafrost Peatland, Northeast China

The rhizosphere microenvironment is crucial to plant–soil physiological processes. The differences among microbial communities in the rhizosphere and non-rhizosphere peatland topsoil (0–15 cm) and subsoil (15–30 cm) in five plant communities dominated by Carex schmidtii, Chamaedaphne calyculata, Ledum palustre, Betula fruticosa, and Vaccinium uliginosum, as well as non-rhizosphere soil in discontinuous and continuous permafrost regions, were studied. We found that the bacteria and nifH gene abundances in the C. calyculata rhizosphere soil in the discontinuous permafrost region were higher than those in continuous permafrost region, while the nirK and nifH gene abundances in the non-rhizosphere soil of the discontinuous permafrost region were lower than those in the continuous permafrost region. The ratio of bacteria to fungi decreased and that of nirK to nirS increased significantly from the discontinuous to the continuous permafrost region, indicating that permafrost degradation can change soil microbial community composition. Fungal abundance was higher in the rhizosphere than the non-rhizosphere soils, suggesting that plant roots provide a more suitable environment for fungi. Moreover, the abundances of the topsoil bacteria; the fungi; and the nirK, nirS, and nifH genes were higher than those in the subsoil because of the organic matter from plant litter as a source of nutrients. The microbial abundance in the subsoil was also more affected by nutrient availability. To sum up, the microbial abundance varied among the different types of rhizosphere and non-rhizosphere soils, and the carbon and nitrogen cycling processes mediated by soil microorganisms may be greatly altered due to permafrost degradation under climate warming.

Determination of the genetic diversity and population structure of Vaccinium uliginosum in Northeast China based on the chloroplast matK gene and EST-SSRseq molecular markers

Determination of the genetic diversity and population structure of Vaccinium uliginosum in Northeast China based on the chloroplast matK gene and EST-SSRseq molecular markers

Night-time water relations and gas exchange in cut shoots of five boreal dwarf shrub species: impact of soil water availability.

Recent findings suggest that drought may affect plants' daytime and night-time stomatal regulation differently. However, knowledge of night-time stomatal behaviour in dwarf shrubs growing in boreal ecosystems is lacking. We sampled cut shoots from dwarf shrub species to elucidate their capacity to transpire at night and the effect of drought on stomatal regulation. The shoots' water relations and gas exchange were measured under controlled conditions in a growth chamber. The studied species demonstrated considerable differences in their diurnal water use. The night-time water use percentage of daytime water use (NWU) reached up to 90% in Andromeda polifolia and Vaccinium uliginosum. In Rhododendron tomentosum, Vaccinium myrtillus and Chamaedaphne calyculata, the NWU was 62, 27 and 26%, respectively. The shoots of C. calyculata showed a significant increase (P < 0.001) in the transpiration rate (E) during the night. However, in R. tomentosum, a decrease (P < 0.05) in nightly E was observed. The shoot conductance (g) at the end of the night was lower than daytime g in all studied species, but the difference was not significant for V. uliginosum. Across the species, NWU was negatively related (P < 0.001) to the soil volumetric water content (SWC) in the plant habitat. However, daytime E and g were positively related (P < 0.05) to the habitat SWC. Only in V. myrtillus was night-time E higher (P < 0.05) in dry conditions than in wet conditions. Our results demonstrate high variability in diurnal water relations in dwarf shrubs, which can keep stomata open in the dark even when drought limits daytime g and E.

Determination of Bioactive Compounds in Vaccinium myrtillus L. and Vaccinium uliginosum L. in Armenia

Blueberries is a valuable source of health-promoting bioactive compounds. The objects of this study were the wild blueberry variety Vaccinium myrtillus L. and Vaccinium uliginosum L. growing in Armenia. The total content of phenols, anthocyanins and flavonoids, as well as the composition of organic acids in blueberry fruits and leaves, was studied. Spectrophotometry and HPLC (High-performance liquid chromatography) methods were applied. The results of the research showed that for most of the studied parameters, the Vaccinium uliginosum inferior to the Vaccinium myrtillus.