Browsing by Subject "SPRUCE PICEA-ABIES"

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  • Kanerva, Mikko; Matrenichev, Vsevolod; Layek, Rama; Takala, Timo M.; Laurikainen, Pekka; Sarlin, Essi; Elert, Anna Maria; Yudin, Vladimir; Seitsonen, Jani; Ruokolainen, Janne; Saris, Per (2020)
    The quantitative difference in the antibacterial response was measured for pine rosin and propolis against Staphylococcus aureus ATCC 12598. The activity was studied for fibrous networks that form entirely bio-based cellulose-acetate (CA) materials. The analysis considers the effects of bacterial input, additive dosage, solvent type, variation in preparation, as well as the effect of storage time. Based on the results, the electrospun network structure is dependent on the solvent and the concentration of rosin and propolis. Both rosin and propolis improved the cellulose acetate solution processability, yet they formed beads at high concentrations. Rosin and propolis created strong antibacterial properties when these material systems were immersed in the liquid for 24 h at room temperature. The response remained visible for a minimum of two months. The electrospun networks of water and DMAc solvent systems with 1 to 5 wt% rosin content were clearly more efficient (i.e., decrease of 4 to 6 logs in colony forming units per mL) than the propolis networks, even after two months. This efficiency is likely due to the high content of abietic acids present in the rosin, which is based on the Fourier transform infrared spectra. The results of the additional analysis and cell cultivation with dermal fibroblast cells indicated an impairing effect on skin tissue by the rosin at a 1 wt% concentration compared to the pure CA fibers.
  • Hui, Nan; Liu, Xinxin; Kotze, D. Johan; Jumpponen, Ari; Francini, Gaia; Setala, Heikki (2017)
    Ectomycorrhizal (ECM) fungi are important mutualists for the growth and health of most boreal trees. Forest age and its host species composition can impact the composition of ECM fungal communities. Although plentiful empirical data exist for forested environments, the effects of established vegetation and its successional trajectories on ECM fungi in urban greenspaces remain poorly understood. We analyzed ECM fungi in 5 control forests and 41 urban parks of two plant functional groups (conifer and broadleaf trees) and in three age categories (10, similar to 50, and > 100 years old) in southern Finland. Our results show that although ECM fungal richness was marginally greater in forests than in urban parks, urban parks still hosted rich and diverse ECM fungal communities. ECM fungal community composition differed between the two habitats but was driven by taxon rank order reordering, as key ECM fungal taxa remained largely the same. In parks, the ECM communities differed between conifer and broadleaf trees. The successional trajectories of ECM fungi, as inferred in relation to the time since park construction, differed among the conifers and broadleaf trees: the ECM fungal communities changed over time under the conifers, whereas communities under broadleaf trees provided no evidence for such age-related effects. Our data show that plant-ECM fungus interactions in urban parks, in spite of being constructed environments, are surprisingly similar in richness to those in natural forests. This suggests that the presence of host trees, rather than soil characteristics or even disturbance regime of the system, determine ECM fungal community structure and diversity. IMPORTANCE In urban environments, soil and trees improve environmental quality and provide essential ecosystem services. ECM fungi enhance plant growth and performance, increasing plant nutrient acquisition and protecting plants against toxic compounds. Recent evidence indicates that soil-inhabiting fungal communities, including ECM and saprotrophic fungi, in urban parks are affected by plant functional type and park age. However, ECM fungal diversity and its responses to urban stress, plant functional type, or park age remain unknown. The significance of our study is in identifying, in greater detail, the responses of ECM fungi in the rhizospheres of conifer and broadleaf trees in urban parks. This will greatly enhance our knowledge of ECM fungal communities under urban stresses, and the findings can be utilized by urban planners to improve urban ecosystem services.
  • Leppälammi-Kujansuu, Jaana; Aro, Lasse; Salemaa, Maija; Hansson, Karna; Kleja, Dan Berggren; Helmisaari, Heljä-Sisko (2014)
  • Tupek, Boris; Mäkipää, Raisa; Heikkinen, Juha; Peltoniemi, Mikko; Ukonmaanaho, Liisa; Hokkanen, Tatu; Nojd, Pekka; Nevalainen, Seppo; Lindgren, Martti; Lehtonen, Aleksi (2015)
    Soil carbon models serving national greenhouse gas (GHG) inventories need precise litter input estimates that typically originate from regionally-averaged and species-specific biomass turnover rates. We compared the foliar turnover rates estimated from long-term measurements by two methods: the needle-cohort based turnover rates (NT; 1064 Scots pine and Norway spruce stands), used in Finnish GHG inventory, and litterfall-biomass based turnover rates (LT; 40 Scots pine, Norway spruce, and silver and downy birch stands). For evergreens, regionally averaged NT values (+/- SD) (0.139 +/- 0.01, 0.1 +/- 0.009 for spruce south and north of 64 degrees N, and 0.278 +/- 0.016, 0.213 +/- 0.028 for pine, respectively) were greater than those used in the GHG inventory model in Finland (0.1, 0.05 for spruce in the south and north, and 0.245, 0.154 for pine, respectively). For deciduous forests, averaged LT values SD (0.784 +/- 0.162, 0.634 +/- 0.093 for birch in the south and north) were close to that (0.79) currently used for the whole of Finland.
  • Pitkänen, Leena M.; Heinonen, Marina; Mikkonen, Kirsi S. (2018)
    A growing population and concern over the sufficiency of natural resources for feeding this population has motivated researchers and industries to search for alternative and complementary sources of food ingredients and additives. Numerous plant species and parts of plants are explored as raw materials for food production. An interesting example is wood; to date, few wood-based additives or ingredients are authorized for food use. Wood hemicelluloses, such as softwood galactoglucomannans (GGM), constitute an abundant bioresource that shows a highly potential functionality in edible materials. Spruce GGM—“spruce gum”—acts as a multi-functional emulsion stabilizer, and it could be used in various processed food products, replacing less effective, conventional emulsifiers. Before new materials can be released onto the food market, their safety must be evaluated, according to the Novel Food regulation. This review focuses on the safety aspects that must be considered before polysaccharide- and phenolic-rich plant extracts can be awarded the status of authorized food ingredients. In this review, GGM is presented as a case study and examples are given of plant-based polysaccharides that are already authorized for food purposes. The legislation regarding Novel Food ingredients in Europe is also briefly reviewed.
  • Rissanen, Kaisa; Hölttä, Teemu; Bäck, Jaana (2018)
    Most plant-based emissions of volatile organic compounds are considered mainly temperature dependent. However, certain oxygenated volatile organic compounds (OVOCs) have high water solubility; thus, also stomatal conductance could regulate their emissions from shoots. Due to their water solubility and sources in stem and roots, it has also been suggested that their emissions could be affected by transport in the xylem sap. Yet further understanding on the role of transport has been lacking until present. We used shoot-scale long-term dynamic flux data from Scots pines (Pinus sylvestris) to analyse the effects of transpiration and transport in xylem sap flow on emissions of 3 water-soluble OVOCs: methanol, acetone, and acetaldehyde. We found a direct effect of transpiration on the shoot emissions of the 3 OVOCs. The emissions were best explained by a regression model that combined linear transpiration and exponential temperature effects. In addition, a structural equation model indicated that stomatal conductance affects emissions mainly indirectly, by regulating transpiration. A part of the temperature's effect is also indirect. The tight coupling of shoot emissions to transpiration clearly evidences that these OVOCs are transported in the xylem sap from their sources in roots and stem to leaves and to ambient air.
  • Hänninen, Tuomas; Tukiainen, Pekka; Svedström, Kirsi; Serimaa, Ritva; Saranpää, Pekka; Kontturi, Eero; Hughes, Mark; Vuorinen, Tapani (2012)