Dehydrins in Buds of Main Birch Species under Conditions of Karelia

The composition and seasonal dynamics of stress proteins-dehydrins in the buds of the main birch species (downy birch (Betula pubescens Ehrh.), silver birch (B. pendula Roth)) and its varieties (Karelian birch (B. pendula var. carelica (Mercklin) Hämet-Ahti)), growing in northwest Russia (on the example of the Republic of Karelia) were investigated for the first time. It was shown that the level of low-molecular dehydrins, mainly with a molecular mass of 17 kD, is subjected to major seasonal changes, regardless of the specific features of the birch. The maximal level of 17 kD dehydrin was formed during the autumn preparation of plants to dormancy and was persistently preserved during the cold period of the year. The content of medium-molecular weight dehydrins of 66–69 kD was almost at the same level all year round. Significant inter-and intraspecific polymorphism of the major dehydrins of 17 and 66–69 kD in the buds of downy birch, silver birch, and Karelian birch during dormancy was not found. The significant similarity in the composition of total proteins and dehydrins, as well as the uniform nature of their seasonal changes, mainly 17 kD dehydrin, indicates the phylogenetic proximity and similar mechanisms of adaptation of the main species of the genus Betula L. to the temperate continental climate of Karelia.     

Sucrose-Caused Changes in the Frequency and Localization of Anticlinal Divisions in the Cambial Zone of Silver Birch

This study continues our previous experiments intended to elucidate the role of sucrose in a figured wood formation in silver birch (Betula pendula Roth var. carelica). The purpose of the study was the investigation of the role of sucrose in the regulation of cell division in the cambial zone. Using an earlier-developed technique, sucrose solutions of different concentrations have been delivered into trunk tissues of silver birch. A microscopic analysis of samples collected 28 days after the beginning of the experiment has shown that an increased sucrose concentration in an exogenous solution causes an increase in the frequency of anticlinal cell divisions in the cambial zone. In the case of high sucrose concentrations (10 or 20%), the zone of anticlinal divisions is significantly wider than in variants with low sucrose concentrations, since anticlinal divisions are observed on both phloem and xylem sides and at a larger distance from rays. A comparison of the obtained results with the previous experiments shows that the increased frequency of anticlinal divisions in cambial cells observed in the case of application of 10 or 20% sucrose solutions coincides with an increased parenchymatization of tissues. A revealed localization of anticlinal divisions within the cambial zone indicates that, in the case of the exogenous sucrose uptake, the morphogenesis of conductive tissues in silver birch (Betula pendula Roth var. pendula) occurs in the same way as in Karelian birch (Betula pendula Roth var. carelica). Data presented in this paper agree with the earlier hypothesis that the formation of figured wood similar to that of Karelian birch occurs due to increased sucrose content in trunk tissues.     

The Influence of Location,Tree Age and Forest Habitat Type on Basic Fuel Properties of the Wood of the Silver Birch (<Emphasis Type="Italic">Betula pendula</Emphasis> Roth.) in Poland

The most extensive study to be carried out in Poland, and one of only a few worldwide, regarding the influence of location, tree age and forest habitat type on the basic fuel properties of silver birch (Betula pendula Roth.) wood was conducted in 12 Forestry Districts of the Polish State Forests. The field study included trees in three age groups of approximately 30, 50 and 70 years. The research was carried out in a fresh broadleaved forest (FBF) habitat type, where in Poland silver birch stands predominate in respect of coverage area and merchantable volume. Additionally, for five selected Forestry Districts, a comparative study was conducted in a fresh mixed broadleaved forest (FMBF), the second most important habitat of this tree species. A total of 306 test trees were examined. For every sample, calorific value and contents of ash, carbon, hydrogen, nitrogen, sulphur and chlorine were determined. The results indicated a statistically significant influence of location on the calorific value (p?=?0.0001) and on the contents of ash (p?<?0.0001), carbon (p?<?0.0001), hydrogen (p?<?0.0001), nitrogen (p?<?0.0001) and chlorine (p?<?0.0001) in the analysed wood. Moreover, statistically significant differences were observed between values of ash content (p?=?0.046) and of calorific value (p?=?0.0026) depending on the forest habitat type. Tree age was found to have no significant influence on the calorific value of silver birch wood.     

High pressure effect on photosynthetic properties of green plant leaves

We investigated the effects of high pressure treatment on green plant leaves of two species, red rose (Rosa rubiginosa L.) and silver birch male (Betula pendula Roth). Both species were treated with pressure up to 100 bar in order to explore stress reactions, including desirable or undesirable metabolites in plant. When increasing the pressure, chlorophyll (Chl) fluorescence maximum shifts to the wavelength of about 680 nm for both red rose and silver birch, with shift rates–0.062 nm/bar and–0.082 nm/bar, respectively. High pressure induces the changes of the position for the second fluorescence maximum at approximately 730 nm in both species with the same shift rate–0.083 nm/bar. When increasing pressure the change of the photosynthetic apparatus efficiency decreases for both plant species slowly and nonlinearly. High-pressure treatments irreversibly damaged the leaf tissue and at this way induced changes of Chl fluorescence and photosynthetic efficiency.     

Dehydrin stress proteins in birch buds in regions with contrasting climate

Dehydrin stress proteins were identified in buds of silver birch (Betula pendula Roth) grown in regions with contrasting climate, Karelia and Central Yakutia, using specific antibodies. Two types of dehydrins present in the plant buds, proteins with average (56–73 kDa) and low (14–21 kDa) molecular weight, as well as 17-kDa dehydrin, were detected in all studied plants. The most sensitive to seasonal changes are 14- to 21-kDa dehydrins, the level of which, regardless of the region where the birch grows, significantly increased during the autumn–winter period. The intraspecific polymorphism of dehydrins was more pronounced in B. pendula grown under the sharply continental climate of Yakutia, which is probably due to the peculiarities of the adaptation of woody plants to the extremely low temperatures of the cryolitic zone.     

The use of parameters of chlorophyll <Emphasis Type="Italic">a</Emphasis> fluorescence induction to evaluate the state of plants under anthropogenic load

The physiological state of the leaves of the small-leaved linden (Tilia cordata), silver birch (Betula pendula), and northern white cedar (Thuja occidentalis) under urban conditions was assessed via recording the kinetics of chlorophyll under fluorescence induction. Different sensitivities of the plants to adverse growing conditions were revealed. The most sensitive parameters of the fluorescence JIP test, viz., PI _ABS , F _V/F ₀, and F _V/F _M, were identified as indicators of the physiological state of the urban phytocoenosis. Recommendations for the application of the method for monitoring studies are presented.     

Identification of birch pollen species using FTIR spectroscopy

In this study, the morphology and chemical composition of pollen grains of six birch species (Betula utilis Doorenbos, B. dahurica, B. maximowicziana, B. pendula, B. pubescens and B. humilis) were examined to verify which of these features allow distinguishing them in a more unambiguous way. For this purpose, scanning electron microscopy and light microscopy, as well as Fourier transform infrared (FTIR) spectroscopy and curve-fitting analysis of amide I profile, were performed. The microscopy images show that the pollen grains of B. pubescens, B. pendula and B. humilis are similar in diameter and significantly smaller than those of others species, with the largest diameter observed for B. utilis Doorenbos. However, the results obtained from FTIR spectroscopy indicate that the chemical compositions of B. pubescens and B. pendula are similar, but B. humilis is outlaying. Summarizing, it is not possible to unambiguously state, which feature or which technique is the best for differentiating between the six chosen birch species. However, the study showed that both techniques have potential for identification of birch pollen species.     

Excess of exogenous nitrates inhibits formation of abnormal wood in the Karelian birch

The effect of exogenous nitrate on the sucrose-metabolizing enzyme activities—sucrose synthase (SS) and apoplastic invertase (ApInv)—in the xylem and phloem of the silver (Betula pendula Roth var. pendula) and Karelian (B. pendula var. carelica) birches (the latter is well known for its abnormal, patterned wood) has been studied. A stable correlation between the enzyme activities and deviations in the growth and development of stem vascular tissues during cambial growth has been demonstrated. Formation of the birch wood with a common structure is associated with high SS activity. In this case, the reaction yields UDP glucose, which is utilized mainly for synthesis of the cell wall components of vessels and fiber tracheids. As for the Karelian birch, the SS activity in the xylem formation zone is decreased, which complies with a higher sucrose level in the tissue. The excess sucrose is released into the apoplast to be cleaved by ApInv. The resulting hexoses induce storage metabolism, thereby increasing the amount of storage substances and the share of storage parenchyma cells in the xylem. As a result, the Karelian birch wood acquires large inclusions in the parenchyma, which render a characteristic pattern. A change in the ratio of SS to ApInv activities underlies a great variety in the degree of wood patterning observed in Karelian birch trees. In the common silver birch, the nitrate application increases the sucrose utilization via SS pathway, which results in an increase in wood growth. In the Karelian birch xylem, nitrates lead to a decrease in both the SS (a decrease in wood growth) and ApInv (a decrease in the amount of parenchyma, i.e., normalization of the wood structure). The sucrose metabolizing in the xylem decreases on the background of an increase in its utilization in the phloem, where both enzyme activities elevate. It is assumed that the fact that the Karelian birch distribution range is limited by rich soils can be determined by a shift from intensive apoplastic sucrose utilization zone towards the phloem caused by high doses of nitrogen nutrition.     

<Emphasis Type="Italic">Basidiophora delawarensis</Emphasis>, a new downy mildew species infecting cultivated goldenrod (<Emphasis Type="Italic">Solidago sphacelata</Emphasis>) in the USA

Species in the genus Basidiophora (Oomycota, Peronosporales) are pathogens causing downy mildew disease on several closely related plant hosts in the family Asteraceae, including the genera Conyza, Erigeron, Solidago, and Symphyotrichum. Despite their widespread occurrence, little is known about the diversity, biology, and economic impact of downy mildew pathogens of ornamental or wild plants in the Asteraceae. In June 2017, Solidago sphacelata plants of the cultivar ‘Golden Fleece’ were found in the state of Delaware, USA, showing typical symptoms of downy mildew disease. Initial morphological observations indicated the specimen belonged to the genus Basidiophora. Phylogenetic analysis of a sequence matrix of the partial cox2 mitochondrial gene using Bayesian and maximum likelihood methods showed that the Basidiophora isolate from S. sphacelata represents an undescribed species that is here described as B. delawarensis. This new species constitutes the third accepted species in the genus Basidiophora and can be distinguished from other Basidiophora species by differences in size of sporangia and sporangiophores and nucleotide sequence divergence. This new species poses a potential threat to its host, warranting close monitoring and the implementation of disease management programs.     

Phylogenetic relationships,molecular taxonomy,biogeography of <Emphasis Type="Italic">Betula</Emphasis>, with emphasis on phylogenetic position of Iranian populations

Birch trees inhabiting the high-altitude Hyrcanian forest (the southern shores of the Caspian Sea of Iran and Azerbaijan) are classified in the EN (endangered) category of the International Union for Conservation of Nature (IUCN). Taxonomic status and phylogenetic relationship of Iranian populations, molecular taxonomy, and biogeography of the genus Betula in the world have been considered. Four remnant populations of Betula were selected from north and northwestern parts of Iran. The internal ITS and trnH-psbA intergenic spacer regions were sequenced. Based on the trnH-psbA and ITS, Iranian birch and white birch were placed in a clade, but based on trnH-psbA divided into two subclades. Phylogenetic trees based on ITS and trnH-psbA data did not completely support the morphological classification. Network analysis confirms a close relationship of B. pendula with B. platyphylla and B. papyrifera with B. humilis, and B. ermanii were in a group with the other tetraploid species of the subgenus Neurobetula. Divergence time analysis showed that about 75 Ma ago the Betula genus separated from the other genus of Betulaceae and then divided into two main clades in Oligocene. Our divergence analysis supports that two subgenera of Betulenta and Betulaster are the oldest subgenera in the genus Betula and they date back to Eocene. The ancestral reconstruction suggests that ancestors of the genus Betula originated from Southeast Asia.     

Disease protection and allelopathic interactions of seed-transmitted endophytic pseudomonads of invasive reed grass (<Emphasis Type="Italic">Phragmites australis</Emphasis>)

Background and aims

Non-native Phragmites australis (haplotype M) is an invasive grass that decreases biodiversity and produces dense stands. We hypothesized that seeds of Phragmites carry microbes that improve seedling growth, defend against pathogens and maximize capacity of seedlings to compete with other plants.

Methods

We isolated bacteria from seeds of Phragmites, then evaluated representatives for their capacities to become intracellular in root cells, and their effects on: 1.) germination rates and seedling growth, 2.) susceptibility to damping-off disease, and 3.) mortality and growth of competitor plant seedlings (dandelion (Taraxacum officionale F. H. Wigg) and curly dock (Rumex crispus L.)).

Results

Ten strains (of 23 total) were identified and characterized; seven were identified as Pseudomonas spp. Strains Sandy LB4 (Pseudomonas fluorescens) and West 9 (Pseudomonas sp.) entered root meristems and became intracellular. These bacteria improved seed germination in Phragmites and increased seedling root branching in Poa annua. They increased plant growth and protected plants from damping off disease. Sandy LB4 increased mortality and reduced growth rates in seedlings of dandelion and curly dock.

Conclusions

Phragmites plants associate with endophytes to increase growth and disease resistance, and release bacteria into the soil to create an environment that is favorable to their seedlings and less favorable to competitor plants.

     

Diversity and distribution of leaf mining insects on birches (<Emphasis Type="Italic">Betula</Emphasis> spp.) in Siberia

The diversity and distribution of leaf mining insects developing on birches (Betula spp.) in Siberia were reviewed based on published records and our observations. Analysis of the literature revealed 52 species of leaf miners recorded as feeding on different Betula species in Siberia. Among them, three species were listed under different names and six species were erroneously recorded as birch consumers. Thus, the revised list of birch leaf miners contains 44 species. Five moth and four sawfly species are mentioned in the literature as pests of Betula. Four sawflies are known to be invasive in North America. Our collections comprised 25 species, including the micro-moth Stigmella continuella (Lepidoptera, Nepticulidae), a new species for Siberia found in Novosibirsk. Immature stages of 15 species were identified using DNA barcoding. Twenty species were recorded from several regions of Siberia for the first time. The dominant group is Lepidoptera (31 species), followed by Coleoptera (7), Hymenoptera (5), and Diptera (1). Two-thirds of all the known leaf miners develop exclusively on birches; the remaining species also colonize alders (Alnus, Betulaceae), some Rosaceae, Salicaceae, and Ulmaceae. In our observations, the majority of insects (96%) developed on B. pendula. About half of them were also observed on the East Asian birches B. dahurica, B. divaricata, B. costata, B. ermanii, and B. gmelinii; five species were found on the North American birches B. occidentalis and B. papyrifera. All the leaf mining species listed in our paper for Siberia also occur in Europe. The similarity between the miner faunas of these regions is discussed and it is warned about possible errors in diagnostics of the Siberian species using the keys and catalogues for the European fauna. The importance of DNA barcoding in the study of the local insect faunas of poorly explored regions is also emphasized.     

Removal of birch as a means of protecting raised bog mossy vegetation <Emphasis Type="Italic">Ledo</Emphasis>-<Emphasis Type="Italic">Sphagnetum magellanici</Emphasis>

Raised bogs dominated by the vegetation association Ledo-Sphagnetum magellanici Sukopp 1959 em. Neuhäusl 1969 are a valuable and ecologically important plant community that occurs in Central Europe. They develop in impervious depressions with precipitation as the only water source, and are particularly sensitive to drainage, climate change, eutrophication and overgrowing by trees and shrubs. The high pressure of threat justifies taking protective measures. This research focused on the effects of the removal of birch from two bogs, which were dominated by two birch species (Betula pubescens, B. pendula) and also included stands of Scots pine (Pinus sylvestris); the bogs are located in northeastern Poland and showed signs of drying. The trees were removed in early spring 2008. To capture the response to tree cutting, vegetation monitoring was performed for 7 years. The results were compared to pre-cutting environmental conditions (precipitation, temperature, air transpiration). At the first site, which was drained at the beginning of the twentieth century, the ground water level initially decreased; then, from 2010 onwards, the level stabilised and exhibited a negative correlation with the average annual air temperature. While the second site exhibited no significant differences in the ground water table, a correlation with the average annual rainfall was found. At both sites, there was an increase in the coverage of species appropriate for raised bogs, Oxycocco-Sphagnatea Br.-Bl. et R. Tx. 1943, whereas only the second site had significant coverage of these species. These actions improved the habitat conditions and initiated the process of raised bog restoration at that site because Oxycocco-Sphagnatea species cover and frequency increased.     

Investigation of the photosynthetic activity of bark phelloderm of arboreous plants using the fluorescent method

Seasonal changes in the characteristics of chlorophyll fluorescence were studied in the bark of several species of trees originating in various climatic zones: Siberian cedar (Pinus sibirica), larch (Larix sibirica), eastern arborvitae (Thuja occidentalis), pendent white birch (Betula pendula), wild black cherry (Padus virginiana), horse chestnut (Aesculus hippocastanum), red oak (Quercus rubra), Manchurian catalpa (Catalpa bungei), linden (Tilia cordata), goat willow (Salix caprea), Amur cherry (Padus maackii), and apple Korichnaya (Malus domestrica B.). Tree bark has a sufficient amount of chlorophyll for measuring the parameters of chlorophyll fluorescence throughout the year. The relative yield of the variable fluorescence of chlorophyll (F _v/F _m) can be used to assess seasonal changes in the physiological state of various trees.     

Effect of Glutamine Synthetase Gene Overexpression in Birch (<Emphasis Type="Italic">Betula pubescens</Emphasis>) Plants on Auxin Content and Rooting in vitro

The effects of transformation of downy birch (Betula pubescens Ehrh.) with the GS1 gene encoding the cytosolic form of glutamine synthetase on the rooting of plants in vitro was studied. The transgenic plants had an elevated content of glutamine as well as glutamic and aspartic acids and rooted more rapidly than the control plants. Rooting on a medium containing the glutamine synthetase inhibitor phosphinothricin prevented the accumulation of auxin in birch plants carrying the GS1 gene, indicating the involvement of this enzyme in raising the level of auxins in the transgenic plants. The correlation between the increase in the auxin levels in the transgenic plants carrying the glutamine synthetase gene and the increase in the rooting rate is shown for the first time.     

An ethnobotany of the Lukomir Highlanders of Bosnia &amp; Herzegovina

Background

This aim of this study is to report upon traditional knowledge and use of wild medicinal plants by the Highlanders of Lukomir, Bjela?nica, Bosnia and Herzegovina (B&H). The Highlanders are an indigenous community of approximately 60 transhumant pastoralist families who speak Bosnian (Bosanski) and inhabit a highly biodiverse region of Europe. This paper adds to the growing record of traditional use of wild plants within isolated communities in the Balkans.

Methods

An ethnobotanical study using consensus methodology was conducted in Lukomir in Bjela?nica’s mountains and canyons. Field work involved individual semi-structured interviews during which informants described plants, natural product remedies, and preparation methods on field trips, garden tours, while shepherding, or in settings of their choice. Plant use categories were ranked with informant consensus factor and incorporated into a phylogenetic tree. Plants cited were compared to other ethnobotanical surveys of the country.

Results

Twenty five people were interviewed, resulting in identification of 58 species (including two subspecies) from 35 families, which were cited in 307 medicinal, 40 food, and seven material use reports. Individual plant uses had an average consensus of five and a maximum consensus of 15 out of 25. There were a number of rare and endangered species used as poisons or medicine that are endemic to Flora Europaea and found in Lukomir. Ten species (including subspecies) cited in our research have not previously been reported in the systematic ethnobotanical surveys of medicinal plant use in B&H: (Elymus repens (L.) Gould, Euphorbia myrsinites L., Jovibarba hirta (L.) Opiz, Lilium bosniacum (Beck) Fritsch, Matricaria matricarioides (Less.) Porter ex Britton, Phyllitis scolopendrium (L.) Newman, Rubus saxatilis L., Silene uniflora Roth ssp. glareosa (Jord.) Chater & Walters, Silene uniflora Roth ssp. prostrata (Gaudin) Chater & Walters, Smyrnium perfoliatum L.). New uses not reported in any of the aforementioned systematic surveys were cited for a total of 28 species. Thirteen percent of medicinal plants cited are endemic: Helleborus odorus Waldst. et Kit., Gentiana lutea L., Lilium bosniacum (Beck) Fritsch, Silene uniflora Roth ssp. glareosa (Jord.) Chater & Walters., Silene uniflora Roth ssp. prostrata (Gaudin) Chater & Walters, Salvia officinalis L., Jovibarba hirta (L.) Opiz, and Satureja montana L.

Conclusions

These results report on the cohesive tradition of medicinal plant use among healers in Lukomir, Bosnia and Herzegovina. This work facilitates the community’s development by facilitating local and international conversations about their traditional medicine and sharing insight for conservation in one of Europe’s most diverse endemic floristic regions, stewarded by one of Europe’s last traditional Highland peoples.

     

Construction of a sequence-based bin map and mapping of QTLs for downy mildew resistance at four developmental stages in Chinese cabbage (<Emphasis Type="Italic">Brassica rapa</Emphasis> L. ssp. <Emphasis Type="Italic">pekinensis</Emphasis>)

Specific-locus amplified fragment sequencing is a high-resolution method for genetic mapping, genotyping, and single nucleotide polymorphism (SNP) marker discovery. Previously, a major QTL for downy mildew resistance, BraDM, was mapped to linkage group A08 in a doubled-haploid population derived from Chinese cabbage lines 91–112 and T12–19. The aim of the present study was to improve the linkage map and identify the genetic factors involved in downy mildew resistance. We detected 53,692 high quality SLAFs, of which 7230 were polymorphic, and 3482 of the polymorphic markers were used in genetic map construction. The final map included 1064 bins on ten linkage groups and was 858.98 cM in length, with an average inter-locus distance of 0.81 cM. We identified six QTLs that are involved in downy mildew resistance. The four major QTLs, sBrDM8, yBrDM8, rBrDM8, and hBrDM8, for resistance at the seedling, young plant, rosette, and heading stages were mapped to A08, and are identical to BraDM. The two minor resistance QTLs, rBrDM6 (A06) and hBrDM4 (A04), were active at the rosette and heading stages. The major QTL sBrDM8 defined a physical interval of ~228 Kb on A08, and a serine/threonine kinase family gene, Bra016457, was identified as the possible candidate gene. We report here the first high-density bin map for Chinese cabbage, which will facilitate mapping QTLs for economically important traits and SNP marker development. Our results also expand knowledge of downy mildew resistance in Chinese cabbage and provide three SNP markers (A08-709, A08-028, and A08-018) that we showed to be effective when used in MAS to breed for downy mildew resistance in B. rapa.