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Baoru Yang - One of the best experts on this subject based on the ideXlab platform.

Laura Jaakola - One of the best experts on this subject based on the ideXlab platform.

  • abscisic acid regulates anthocyanin biosynthesis and gene expression associated with cell wall modification in ripening Bilberry vaccinium myrtillus l fruits
    Frontiers in Plant Science, 2018
    Co-Authors: Katja Karppinen, Hely Häggman, Pinja Tegelberg, Laura Jaakola
    Abstract:

    Ripening of non-climacteric Bilberry (Vaccinium myrtillus L.) fruit is characterized by a high accumulation of health-beneficial anthocyanins. Plant hormone abscisic acid (ABA) and sucrose have been shown to be among the central signaling molecules coordinating non-climacteric fruit ripening and anthocyanin accumulation in some fruits such as strawberry. Our earlier studies have demonstrated an elevation in endogenous ABA level in Bilberry fruit at the onset of ripening indicating a role for ABA in the regulation of Bilberry fruit ripening. In the present study, we show that the treatment of unripe green Bilberry fruits with exogenous ABA significantly promotes anthocyanin biosynthesis and accumulation both in fruits attached and detached to the plant. In addition, ABA biosynthesis inhibitor, fluridone, delayed anthocyanin accumulation in bilberries. Exogenous ABA also induced the expression of several genes involved in cell wall modification in ripening Bilberry fruits. Furthermore, silencing of VmNCED1, the key gene in ABA biosynthesis, was accompanied by the down-regulation in the expression of key anthocyanin biosynthetic genes. In contrast, the treatment of unripe green Bilberry fruits with exogenous sucrose or glucose did not lead to an enhancement in the anthocyanin accumulation neither in fruits attached to plant nor in post-harvest fruits. Moreover, sugars failed to induce the expression of genes associated in anthocyanin biosynthesis or ABA biosynthesis while could elevate expression of some genes associated with cell wall modification in post-harvest Bilberry fruits. Our results demonstrate that ABA plays a major role in the regulation of ripening-related processes such as anthocyanin biosynthesis and cell wall modification in Bilberry fruit, whereas sugars seem to have minor regulatory roles in the processes. The results indicate that the regulation of Bilberry fruit ripening differs from strawberry that is currently considered as a model of non-climacteric fruit ripening. In this study, we also identified transcription factors, which expression was enhanced by ABA, as potential regulators of ABA-mediated Bilberry fruit ripening processes.

  • changes in the abscisic acid levels and related gene expression during fruit development and ripening in Bilberry vaccinium myrtillus l
    Phytochemistry, 2013
    Co-Authors: Katja Karppinen, Elina Hirvela, Tiina Nevala, Nina Sipari, Marko Suokas, Laura Jaakola
    Abstract:

    Abscisic acid (ABA) is a natural plant hormone playing an important role in many physiological processes including fruit ripening and is also recently found to be potential for biomedical applications. This study was aimed to measure ABA levels and its biosynthesis in Bilberry (Vaccinium myrtillus L.), which is one of the best sources of anthocyanins. Five ABA biosynthetic genes were isolated from Bilberry and their expression profiles were studied in Bilberry tissues, particularly during berry development. The level of ABA highly increased at the onset of Bilberry fruit ripening, at the stage when expression of anthocyanin biosynthetic genes, chalcone synthase (VmCHS) and anthocyanidin synthase (VmANS), also increased. In fully ripe berries and leaves, ABA levels were lower but none was detected in Bilberry stem or rhizome. The expression of 9-cis-epoxycarotenoid dioxygenase (VmNCED1) and putative neoxanthin synthase (VmNSY) was high in berry tissues and their expression increased markedly at the onset of berry ripening along with the accumulation of ABA. In contrast, the expression of zeaxanthin epoxidase (VmZEP), short-chain dehydrogenase/reductase (VmSDR/ABA2) and aldehyde oxidase (VmAO) were most highly associated with leaf tissues with no obvious relation to ABA content during berry development. The obtained results indicate that the ABA biosynthesis may play an important role in the regulation of ripening of non-climacteric Bilberry fruits through transcriptional regulation of key ABA biosynthetic genes.

  • phenolic composition and antioxidant capacity of Bilberry vaccinium myrtillus leaves in northern europe following foliar development and along environmental gradients
    Journal of Chemical Ecology, 2010
    Co-Authors: Francoise Martz, Laura Jaakola, Riitta Julkunentiitto, Sari Stark
    Abstract:

    Bilberry is a characteristic field layer species in the boreal forests and is an important forage plant for herbivores of the North European ecosystem. Bilberry leaves contain high levels of phenolic compounds, especially hydroxycinnamic acids, flavonols, catechins, and proanthocyanidins. We investigated the phenolic composition of Bilberry leaves in two studies, one following foliar development in forest and open areas, and the other along a wide geographical gradient from south to north boreal forests in Finland. An analysis of Bilberry leaves collected in open and forest areas showed that major phenolic changes appeared in the first stages of leaf development, but, most importantly, synthesis and accumulation of flavonoids was delayed in the forest compared to the high light sites. Sampling along a geographical gradient in the boreal zone indicated that leaves from higher latitudes and higher altitudes had greater soluble phenolic and flavonol levels, higher antioxidant capacity, and lower contents of chlorogenic acid derivatives. The ecological significance of the results is discussed.

  • Identification of phenolic compounds from lingonberry (Vaccinium vitis-idaea L.), Bilberry (Vaccinium myrtillus L.) and hybrid Bilberry (Vaccinium x intermedium Ruthe L.) leaves.
    Journal of Agricultural and Food Chemistry, 2009
    Co-Authors: Juho Hokkanen, Sampo Mattila, Laura Jaakola, Anna Maria Pirttilä, Ari Tolonen
    Abstract:

    Phenolic compounds from leaves of lingonberry (Vaccinium vitis-idaea L.), Bilberry (Vaccinium myrtillus L.), and the natural hybrid of Bilberry and lingonberry (Vaccinium x intermedium Ruthe L., hybrid Bilberry) were identified using LC/TOF-MS and LC/MS/MS after extraction from the plant material in methanol in an ultrasonicator. The phenolic profiles in the plants were compared using the LC/TOF-MS responses. This is the first thorough report of phenolic compounds in hybrid Bilberry. In total, 51 different phenolic compounds were identified, including flavan-3-ols, proanthocyanidins, flavonols and their glycosides, and various phenolic acid conjugates. Of the identified compounds, 35 were detected in Bilberry, 36 in lingonberry, and 46 in the hybrid. To our knowledge, seven compounds were previously unreported in Vaccinium genus and many of the compounds are reported for the first time from Bilberry and lingonberry.

  • Bilberry in vitro protocols and analyses of phenolic compounds.
    Methods in molecular biology (Clifton N.J.), 2009
    Co-Authors: Laura Jaakola, Kaisu Riihinen, Hely Häggman, Anja Hohtola
    Abstract:

    Bilberry or European blueberry (Vaccinium myrtillus L.) belongs to the most significant family of wild berries in Northern Europe and is recognized for its bioactive properties. Its fruits and leaves are rich with phenolic compounds, in particular flavonoids. Their health benefits have received notable attention in recent years. Bilberry is one of the richest sources of the anthocyanins, a subclass of flavonoids. The interest in Bilberry cultivation is growing because of the high value of the fruit in global food markets. Tissue culture provides an efficient propagation method for the selected Bilberry genotypes both for the breeding and cultivation purposes. This chapter describes the protocol of Bilberry in vitro propagation and for the analyses of phenolic compounds.

Kjell Sjöberg - One of the best experts on this subject based on the ideXlab platform.

  • Effects of clear-cutting and single-tree selection harvests on herbivorous insect larvae feeding on Bilberry (Vaccinium myrtillus) in uneven-aged boreal Picea abies forests
    Forest Ecology and Management, 1996
    Co-Authors: Ola Atlegrim, Kjell Sjöberg
    Abstract:

    Abstract In uneven-aged boreal Picea abies forests in north-eastern Sweden, the effects of clear-cutting and single-tree selection on herbivorous insect larvae feeding on Bilberry (Vaccinium myrtillus) were studied. Abundance of geometrids and exposed folivorous larvae were significantly lower in clear-cut areas than in selection felled and uncut controls. Significantly lower total abundance of herbivorous larvae were found in clear-cuttings compared to uncut controls. Both stem and leaf damage were significantly higher in selection fellings and controls than in clear-cuttings. The dry biomass consumption per shoot and per larva were significantly higher in selection fellings and uncut controls than in clear-cuttings. Lower availability and quality of Bilberry may explain the reduced abundance of larvae and the reduced consumption of Bilberry by larvae in clear-cuttings. The entire tree layer is removed when the forest is clear-cut, and drastic changes in abiotic factors are probably the ultimate reason for the observed responses of both Bilberry and larvae. Selection felling leaves an intact, although sparser, tree layer following harvest, and abiotic factors are probably only moderately affected. The moderate changes of abiotic factors are probably the reason for small effects on both Bilberry and larvae by selection felling. Our results suggest that clear-cutting negatively affects Bilberry, herbivorous larvae feeding on Bilberry, and their interaction. Contrary to the negative effects of clear-cutting, Bilberry, insect larvae and their interaction in selection felling seems to resemble that in uncut forest. Because exposed larvae feeding on Bilberry are known to be an important food commonly used by birds during their breeding, it could be of significance that forest harvesting has only moderate effects on Bilberry and larvae.

  • Response of Bilberry (Vaccinium myrtillus) to clear-cutting and single-tree selection harvests in uneven-aged boreal Picea abies forests
    Forest Ecology and Management, 1996
    Co-Authors: Ola Atlegrim, Kjell Sjöberg
    Abstract:

    Abstract The aim was to analyse the short-term effects (0–4 years) of selection fellings and clear-cutting on Bilberry (Vaccinium myrtillus), one of the dominant field layer plants in the Swedish boreal coniferous forests. Bilberry is a major source of food for many herbivores. The effects of forest harvesting were studied on Bilberry characteristics of potential importance for herbivores. Five characters of Bilberry growth (vegetative investment, shoot survival, ground cover, shoot weight and production of current annual shoots), two of reproduction (reproductive investment and success) and four of chemical composition (water, nitrogen, carbon and phenol content) were measured. Sunlight reaching the field layer was also measured. Significantly more sunlight reached the field layer, while vegetative investment and shoot survival of Bilberry were significantly lower in clear-cuttings than in selective fellings and uncut controls. Ground cover of Bilberry was significantly higher in control forests than in selection fellings and clear-cuttings. Production of current shoots are significantly higher in uncut controls than in clear-cuttings. Water content was significantly lower, while carbon and phenol content was significantly higher in Bilberry shoots growing in clear-cuttings than in uncut controls. Nitrogen content, reproductive investment and reproductive success were not affected by the different practices. Bilberry was severely affected by clear-cutting. Low vegetative investment, shoot survival, ground cover and production of current annual shoots suggests a poor performance of Bilberry following clear-cutting. Thus, in clear-cuttings, herbivores feeding on Bilberry have a lower amount of shoots available to them and, as indicated by the increased phenol content, the quality of the Bilberry also may be reduced. In selection fellings, Bilberry ground cover was reduced and spatial distribution was more patchy than in controls. However, vegetative investment and shoot survival of Bilberry in selection fellings did not differ from uncut control, but were significantly higher than in clear-cuttings. In contrast to clear-cuttings, phenol content of Bilberry shoots did not increase following selection felling. Therefore, over the 4-year term of our study, selection felling seems to provide herbivores with a Bilberry vegetation similar to that of the uncut controls. Our results suggest that selective felling, compared with clear-cutting, results in a Bilberry field layer of higher availability and quality, which might influence the ecology of many herbivores in the boreal coniferous habitats.

Nadia Mulinacci - One of the best experts on this subject based on the ideXlab platform.

  • Phenolic distribution in liquid preparations of Vaccinium myrtillus L. and Vaccinium vitis idaea L.
    Phytochemical Analysis, 2013
    Co-Authors: Francesca Ieri, Sara Martini, Marzia Innocenti, Nadia Mulinacci
    Abstract:

    Introduction Liquid preparations such as tinctures and ‘bud extracts’ of Bilberry and lingonberry are typical products used in some European countries but they have not been widely studied to date. Objective Our aim was to define a phytochemical profile in terms of phenolic compounds for liquid preparations of Vaccinium myrtillus L. (Bilberry) and Vaccinium vitis idaea L. (lingonberry) foliar tissues, and evaluate their stability. Methods Up to 17 extracts of lingonberry, and Bilberry have been analysed by HPLC equipped with a diode-array detector (DAD) in combination with MS. Some of these samples were freshly prepared (laboratory extracts). Results Phenolic profiles of the bud extracts and tinctures of Bilberry and lingonberry were obtained at 330 nm, typical of the cinnamoyl compounds and suitable to distinguish these two species. Analogously, the profiles at 280 nm were used to detect the arbutin derivatives recognised as the typical markers of lingonberry leaves only. Among the cinnamoyl derivatives, chlorogenic acid was the main compound found in Bilberry samples, while caffeoyl arbutin was the principal marker in lingonberry samples. In quantitative terms, the hydroxycinnamic acids were the main class in Bilberry bud extracts ranging between 4.67 and 6.81 mg/L (from 52 to 84% of the total phenols). The young sprouts of this species, independently from the extraction mixture, show a higher phenolic content than adult leaves of the same plant. Conclusions The analytical method allowed to define fingerprints of Bilberry and lingonberry liquid preparations. Moreover, without applying accelerated ageing protocols, the stability over time of 11 samples was evaluated up to 6 months, demonstrating negligible variations. Copyright © 2013 John Wiley & Sons, Ltd.

Ola Atlegrim - One of the best experts on this subject based on the ideXlab platform.

  • Indirect effects of ant predation (Hymenoptera: Formicidae) on Bilberry Vaccinium myrtillus
    European Journal of Entomology, 2005
    Co-Authors: Ola Atlegrim
    Abstract:

    Bilberry (Vaccinium myrtillus L.) is one of the dominant plants of the Fennoscandian boreal coniferous forest and consti- tutes a major food source for many insect herbivores. A common ant species in these forests is the wood ant Formica (Formica) aquilonia Yarrow, which preys heavily on other invertebrates within its territories. The aim of this study was to investigate whether aquilonia's predation on the insect herbivores may have indirect positive or negative effects on Bilberry. Damage to the Bilberry, its vegetative growth and reproduction were quantified in order to contrast localities close to (2 m) and far away from (50 m) ant nests. Close to ant nests, herbivore damage to the Bilberry was significantly lower and reproductive success, i.e. proportion of flowers succeeding to berries, significantly higher. The results of this study therefore suggest that distance to aquilonia nests, and thus preda- tion from ants, can significantly affect herbivore damage to the Bilberry and its reproductive success (supporting the hypothesis of a top down effect in this three-trophic-level system). Vegetative growth, i.e., density and biomass of current year shoots, and reproduc- tive investment, i.e., proportion of current year shoots with flower, of the Bilberry was, however, not affected by distance to ant nests, indicating that the Bilberry can also compensate for losses due to herbivory.

  • Effects of clear-cutting and single-tree selection harvests on herbivorous insect larvae feeding on Bilberry (Vaccinium myrtillus) in uneven-aged boreal Picea abies forests
    Forest Ecology and Management, 1996
    Co-Authors: Ola Atlegrim, Kjell Sjöberg
    Abstract:

    Abstract In uneven-aged boreal Picea abies forests in north-eastern Sweden, the effects of clear-cutting and single-tree selection on herbivorous insect larvae feeding on Bilberry (Vaccinium myrtillus) were studied. Abundance of geometrids and exposed folivorous larvae were significantly lower in clear-cut areas than in selection felled and uncut controls. Significantly lower total abundance of herbivorous larvae were found in clear-cuttings compared to uncut controls. Both stem and leaf damage were significantly higher in selection fellings and controls than in clear-cuttings. The dry biomass consumption per shoot and per larva were significantly higher in selection fellings and uncut controls than in clear-cuttings. Lower availability and quality of Bilberry may explain the reduced abundance of larvae and the reduced consumption of Bilberry by larvae in clear-cuttings. The entire tree layer is removed when the forest is clear-cut, and drastic changes in abiotic factors are probably the ultimate reason for the observed responses of both Bilberry and larvae. Selection felling leaves an intact, although sparser, tree layer following harvest, and abiotic factors are probably only moderately affected. The moderate changes of abiotic factors are probably the reason for small effects on both Bilberry and larvae by selection felling. Our results suggest that clear-cutting negatively affects Bilberry, herbivorous larvae feeding on Bilberry, and their interaction. Contrary to the negative effects of clear-cutting, Bilberry, insect larvae and their interaction in selection felling seems to resemble that in uncut forest. Because exposed larvae feeding on Bilberry are known to be an important food commonly used by birds during their breeding, it could be of significance that forest harvesting has only moderate effects on Bilberry and larvae.

  • Response of Bilberry (Vaccinium myrtillus) to clear-cutting and single-tree selection harvests in uneven-aged boreal Picea abies forests
    Forest Ecology and Management, 1996
    Co-Authors: Ola Atlegrim, Kjell Sjöberg
    Abstract:

    Abstract The aim was to analyse the short-term effects (0–4 years) of selection fellings and clear-cutting on Bilberry (Vaccinium myrtillus), one of the dominant field layer plants in the Swedish boreal coniferous forests. Bilberry is a major source of food for many herbivores. The effects of forest harvesting were studied on Bilberry characteristics of potential importance for herbivores. Five characters of Bilberry growth (vegetative investment, shoot survival, ground cover, shoot weight and production of current annual shoots), two of reproduction (reproductive investment and success) and four of chemical composition (water, nitrogen, carbon and phenol content) were measured. Sunlight reaching the field layer was also measured. Significantly more sunlight reached the field layer, while vegetative investment and shoot survival of Bilberry were significantly lower in clear-cuttings than in selective fellings and uncut controls. Ground cover of Bilberry was significantly higher in control forests than in selection fellings and clear-cuttings. Production of current shoots are significantly higher in uncut controls than in clear-cuttings. Water content was significantly lower, while carbon and phenol content was significantly higher in Bilberry shoots growing in clear-cuttings than in uncut controls. Nitrogen content, reproductive investment and reproductive success were not affected by the different practices. Bilberry was severely affected by clear-cutting. Low vegetative investment, shoot survival, ground cover and production of current annual shoots suggests a poor performance of Bilberry following clear-cutting. Thus, in clear-cuttings, herbivores feeding on Bilberry have a lower amount of shoots available to them and, as indicated by the increased phenol content, the quality of the Bilberry also may be reduced. In selection fellings, Bilberry ground cover was reduced and spatial distribution was more patchy than in controls. However, vegetative investment and shoot survival of Bilberry in selection fellings did not differ from uncut control, but were significantly higher than in clear-cuttings. In contrast to clear-cuttings, phenol content of Bilberry shoots did not increase following selection felling. Therefore, over the 4-year term of our study, selection felling seems to provide herbivores with a Bilberry vegetation similar to that of the uncut controls. Our results suggest that selective felling, compared with clear-cutting, results in a Bilberry field layer of higher availability and quality, which might influence the ecology of many herbivores in the boreal coniferous habitats.