Juncus Acutiflorus Research Articles

Synopsis of the order Juncales (Liliopsida) in Ukraine

Juncales is an order of vascular plants with cosmopolitan distribution. Two families of Juncales are present in flora of Ukraine: Juncaceae and Cyperaceae. Through 1985–2021, we conducted comprehensive revision of Juncales in Ukraine. The aim of this research was to compile a checklist of Juncales species in the flora of Ukraine. Our research is based on herbarium materials, literature data and field trips. We collected data in many herbariums of Ukraine and other countries. Our understanding of the taxa was further supplemented by field observations in mountainous (Carpathians and Crimea) and plain territories of Ukraine. Also, we collected information about Juncales species from numerous literature sources. For each taxon, we provided nomenclatural citation and basic synonyms. According to our data, the order Juncales in the flora of Ukraine contains 188 species, belonging to 19 genera. Lists of Juncales species can be found in many thorough publications. For a long time, Checklist of Mosyakin & Fedoronchuk (1999) was the main list in the nomenclature of vascular plants in Ukraine. To date, many nomenclature and taxonomic changes have been accumulated. For example, we accept genera Schoenoplectiella and Oreojuncus here. Researchers have found many new species for the territory of Ukraine. This information can be found in numerous publications, but is fragmented. Therefore, we have compiled an updated summary of the Juncales species. In Ukrainian territory, Juncales species are considered both widespread and rare. We refer to the rarest species Carex alba, C. bicolor, C. bohemica, C. brunnescens, C. buxbaumii, C. depauperata, C. fuliginosa, C. globularis, C. heleonastes, C. lachenalii, C. loliacea, C. obtusata, C. pediformis, C. rupestris, C. strigosa, Cyperus longus, Eleocharis multicaulis, E. oxylepis, Fimbristylis bisumbellata, Juncus acutiflorus, J. soranthus, J. subnodulosus, Isolepis setacea, Luzula spicata, Schoenoplectus pungens, Trichophorum alpinum, T. cespitosum. Also, the following species are rare: Bolboschoenus yagara, Carex chordorrhiza, C. davalliana, C. dioica, C. hostiana, C. pauciflora, C. secalina, C. vaginata, Cladium mariscus, Eleocharis carniolica, Juncus capitatus, J. castaneus, J. littoralis, J. sphaerocarpus, J. thomasii, J. triglumis, Luzula alpinopilosa, L. sudetica, Schoenoplectiella mucronata, Schoenus ferrugineus.

Synopsis of the order Juncales (Liliopsida) in Ukraine

Juncales is an order of vascular plants with cosmopolitan distribution. Two families of Juncales are present in flora of Ukraine: Juncaceae and Cyperaceae. Through 1985–2021, we conducted comprehensive revision of Juncales in Ukraine. The aim of this research was to compile a checklist of Juncales species in the flora of Ukraine. Our research is based on herbarium materials, literature data and field trips. We collected data in many herbariums of Ukraine and other countries. Our understanding of the taxa was further supplemented by field observations in mountainous (Carpathians and Crimea) and plain territories of Ukraine. Also, we collected information about Juncales species from numerous literature sources. For each taxon, we provided nomenclatural citation and basic synonyms. According to our data, the order Juncales in the flora of Ukraine contains 188 species, belonging to 19 genera. Lists of Juncales species can be found in many thorough publications. For a long time, Checklist of Mosyakin & Fedoronchuk (1999) was the main list in the nomenclature of vascular plants in Ukraine. To date, many nomenclature and taxonomic changes have been accumulated. For example, we accept genera Schoenoplectiella and Oreojuncus here. Researchers have found many new species for the territory of Ukraine. This information can be found in numerous publications, but is fragmented. Therefore, we have compiled an updated summary of the Juncales species. In Ukrainian territory, Juncales species are considered both widespread and rare. We refer to the rarest species Carex alba, C. bicolor, C. bohemica, C. brunnescens, C. buxbaumii, C. depauperata, C. fuliginosa, C. globularis, C. heleonastes, C. lachenalii, C. loliacea, C. obtusata, C. pediformis, C. rupestris, C. strigosa, Cyperus longus, Eleocharis multicaulis, E. oxylepis, Fimbristylis bisumbellata, Juncus acutiflorus, J. soranthus, J. subnodulosus, Isolepis setacea, Luzula spicata, Schoenoplectus pungens, Trichophorum alpinum, T. cespitosum. Also, the following species are rare: Bolboschoenus yagara, Carex chordorrhiza, C. davalliana, C. dioica, C. hostiana, C. pauciflora, C. secalina, C. vaginata, Cladium mariscus, Eleocharis carniolica, Juncus capitatus, J. castaneus, J. littoralis, J. sphaerocarpus, J. thomasii, J. triglumis, Luzula alpinopilosa, L. sudetica, Schoenoplectiella mucronata, Schoenus ferrugineus.

First Report of 'Candidatus Phytoplasma asteris' Associated with Witches' Brooms on Sharp-Flowered Rush (Juncus acutiflorus) in Poland.

Juncus acutiflorus L. (Juncaceae) is a species of rush widespread in Europe, North Africa, and Southwest Asia. The health of sharp-flowered rush is threatened by witches’ brooms occurrence. Typical symptoms are dense masses of shoots, usually growing from a single point, with the resulting structure resembling a broom. Witches’ brooms are typically formed in response to Livia junci (Liviinae, Hemiptera) feeding, oligofag, which typically feeds on Juncus sp. These symptoms are similar to those observed in Juncus articulatus L. (Juncaceae) related to phytoplasma infection in Silesia, Poland (Jarzembowski et al. 2015). In August 2017, samples were collected from nine symptomatic and four asymptomatic plants growing in Jagniątkow, Poland. DNA from 100 mg of inflorescence and leaf samples was extracted using a DNeasy Plant Mini Kit (Qiagen, Syngen Biotech, Wroclaw, Poland) according to the manufacturer’s protocol. Additionally, 10 L. junci specimens (adult and the last larva stage) were collected from symptomatic plants and preserved in ethanol (75%). DNA from the insects (treated as one sample) was extracted using a DNeasy Blood and Tissue Kit (Qiagen, Syngen Biotech). The extracts were used as the template in polymerase chain reaction (PCR) assays with the universal phytoplasma primers P1/P7 followed by R16F2/R16R2 (Lee et al. 1998). Additionally, primers rp1/rp2 followed by rp3/rp4, allowing amplification of fragments of rpl22 and rps3 genes (Nakamura et al. 1996), and primers AYsecYF1/AYsec for amplification of secY gene were applied. Water blank samples were included as negative controls. PCR products of expected size for each primer set were amplified from the insects and six symptomatic plants that were assayed. No amplification was observed in symptomless J. acutiflorus samples or in water blanks. Amplicons representing three genetic loci were sequenced at Genomed S.A., Warsaw, Poland. DNA samples were sequenced at least twice in both directions. Sequencing results of the PCR products confirmed that six symptomatic plants and the insects were infected by a phytoplasma. The obtained sequences were nearly identical, and representative sequences of 16S rDNA fragments (accession nos. MG976242 to MG976246), secY gene (MG983765 to MG983769), and ribosomal protein gene (MG983760 to MG983764) from four plants and one insect sample were deposited in GenBank. Determination of the phytoplasma classification group was based on the nucleotide sequence of the F2n/R2 PCR fragment within the 16S gene. Using iPhyClassifier, the online tool for phytoplasma classification (https://plantpathology.ba.ars.usda.gov/cgi-bin/resource/iphyclassifier_legacy.cgi), the sequence of J. acutiflorus phytoplasma shared 99.9% identity with that of the ‘Candidatus Phytoplasma asteris’ reference strain (GenBank accession no. M30790). BLAST analysis performed for ribosomal proteins and secY genes confirmed the highest identity (99%) of analyzed sequences with those of ‘Ca. P. asteris’ (CP015149 and KJ394491, respectively). To our knowledge, this is the first report of a phytoplasma of group 16SrI affecting J. acutiflorus in Poland and in the world. The impact of the detected phytoplasma in the regional ecosystem is being assessed. It is highly probable that L. junci is a possible vector for ‘Ca. P. asteris’.

Detection of habitats colonized by Omphiscola glabra (Gastropoda: Lymnaeidae) on acid soils using indicator plants

The lymnaeid Omphiscola glabra is known to be an intermediate host in the life cycle of Fasciola hepatica and knowing its distribution in the field is important to determine that of the parasite. Looking at indicator plants has been proposed by several authors as one of the most practical ways of carrying out a malacological survey in pastures of a farm. Field investigations on 361 French farms breeding cattle or sheep on acid soils were thus carried out for 36 years in March or April to list indicator plant species in seven types of habitats colonized by O. glabra , and determine the characteristics of their habitats (area, snail density) for each indicator plant. Six plant species: Agrostis stolonifera , Dactylis glomerata , Glyceria fluitans , Juncus acutiflorus , Juncus effusus and Lotus uliginosus , were examined in 3137 snail habitats. J. effusus was the best indicator species to detect snail populations in five habitat types, while J. acutiflorus was the best indicator for snail populations living in spring heads. The other four plant species characterized only a few populations. Snail habitats detected with J. acutiflorus , J. effusus or L. uliginosus were significantly larger in area, while the density of overwintering snails was significantly lower in habitats with G. fluitans . These initial results suggest that J. effusus is a good indicator for the detection of O. glabra in the acid soils of central France. However, additional studies are required to test its limitations in the field.

Differential responses of two wetland graminoids to high ammonium at different pH values.

Enhanced soil ammonium (NH4+) concentrations in wetlands often lead to graminoid dominance, but species composition is highly variable. Although NH4+ is readily taken up as a nutrient, several wetland species are known to be sensitive to high NH4+ concentrations or even suffer toxicity, particularly at low soil pH. More knowledge about differential graminoid responses to high NH4+ availability in relation to soil pH can help to better understand vegetation changes. The responses of two wetland graminoids, Juncus acutiflorus and Carex disticha, to high (2mmol·l(-1) ) versus control (20μmol·l(-1) ) NH4+ concentrations were tested in a controlled hydroponic set up, at two pH values (4 and 6). A high NH4+ concentration did not change total biomass for these species at either pH, but increased C allocation to shoots and increased P uptake, leading to K and Ca limitation, depending on pH treatment. More than 50% of N taken up by C.disticha was invested in N-rich amino acids with decreasing C:N ratio, but only 10% for J.acutiflorus. Although both species appeared to be well adapted to high NH4+ loadings in the short term, C.disticha showed higher classic detoxifying responses that are early warning indicators for decreased tolerance in the long term. In general, the efficient aboveground biomass allocation, P uptake and N detoxification explain the competitive strength of wetland graminoids at the expense of overall biodiversity at high NH4+ loading. In addition, differential responses to enhanced NH4+ affect interspecific competition among graminoids and lead to a shift in vegetation composition.

The detection of snail host habitats in liver fluke infected farms by use of plant indicators

Field investigations in 361 liver fluke infected cattle- or sheep-breeding farms on acid soil were carried out during thirty years in March and April to record indicator plants in relation to the category of site colonized by the intermediate host of liver fluke, the snail Galba truncatula. Seven types of snail zones and six species of indicator plants were recorded in the 7709 positive sites studied. The most frequent habitats were located at the peripheral extremities of open drainage furrows. Juncus acutiflorus, Juncus effusus, Glyceria fluitans, and Agrostis stolonifera were the indicator plants. Plant indicators were highly efficient (38–80% of variance explained) when used with the size of site area within a hydrographical zone. The identification of positive sites for G. truncatula is a key for controlling the intermediate host on pastures through biological control with predatory molluscs. The positive sites may be detected using a two-step method including first categorization of hydrographical zones and then, within a zone, use of one or several indicator plants (frequently J. acutiflorus).

Edaphic relationships among Cirsio‐Molinietum and related wet grassland communities in lowland Wales

Abstract. Soil properties are characterized for a range of the Molinietalia vegetation types in lowland Wales. In this oceanic region there is overlap in the distribution of various forms of wet pasture dominated by Molinia caerulea and Juncus acutiflorus. There is subtle and continuous variation in species composition among four communities investigated; this has been analysed by Detrended Correspondence Analysis and partitioned between subcommunities recognized in Rodwell (1991). Canonical Variates Analysis indicated that the main differences in soil conditions between the vegetation classes are related to gradients in base‐status; apparent variation in soil fertility may also be significant and requires further investigation. In general, Molinia‐Cirsium dissectum fen‐meadow soils have higher pH, higher Ca‐levels, greater base saturation and lower acidity than Molinia‐Potentilla erecta wet grasslands; those of Juncus‐Galium palustre rush‐pasture and Molinia‐Crepis paludosa mire had relatively high levels of inorganic N. The findings are discussed with reference to ecological and phytosociological relationships, and also in the context of nature conservation.

Seed dispersal by mowing machinery in a Dutch brook valley system

Seed dispersal by mowing machinery was investigated within a grassland reserve. Transported seed numbers amounted to hundreds of thousands. Seeds of 26 species were found on the machinery, including species that play an important role in succession during vegetation restoration (Holcus lanatus, Rhinanthus angustifolius, Anthoxanthum odoratum). Species occurrence was related to field abundance, but not to plant size, seed size or month of first flowering. Species seed amounts were also positively correlated only to their abundance within fields. Several abundant species were not found because they carried no seeds at the cutting date (Caltha palustris, Juncus acutiflorus). There was a difference in species composition within material accumulating in two machinery parts, which was related to their height above ground level. It was concluded that dispersal by mowing machinery is moderately selective towards and against certain species. Seeds were transported from species-rich fields into species-poor fields and vice versa. The seeds transported after mowing a field were partially deposited in the next field. Dispersal by machinery may have a larger impact on the speed of succession in the hay-fields of the Drentse A reserve than any other form of dispersal and establishment from the seed bank. Therefore, it is important for vegetation restoration in practice. However, machinery does not always connect seed sources with restoration areas. Large-scale machinery movement also creates a new form of vegetation dynamics compared to the days of former, more primitive, agricultural use. Both factors have to be considered when attempts are made to restore species-rich vegetation types. It is probable that new methods will not produce the vegetation that once existed.

Nitrate induced iron deficiency chlorosis in Juncus acutiflorus

Chlorosis caused by iron deficiency is commonly associated with high bicarbonate levels in the soil. However, in rare cases such chlorosis has been observed in soils with high nitrate levels. In a dutch rich-fen, chlorosis has been noted in stands of Juncus acutiflorus at locations where groundwater containing high levels of nitrate reached the surface. Experiments revealed that the chlorosis could be attributed to iron deficiency although iron levels in the shoots were well above the known physiological threshold values for iron deficiency. It is postulated that increased nitrate assimilation leads to an increased apoplastic pH and to a concomitant immobilisation of iron and/or lower iron (III) reduction. Moreover free amino acid levels were markedly higher in the iron deficient plants in the field. It was found, however, that the percentage of nitrogen present as free amino acids was not influenced directly by low iron levels but mainly by the C/N ratios in the shoots. Nowadays, nitrate concentrations in ground water as high 1000 µM are no longer an exception in the Netherlands. We propose that strongly increased nitrate inputs may cause iron stress in natural vegetations, especially in wet habitats.

Sheep-Grazing with Different Foraging Efficiences in a Dutch Mixed Grassland

(1) In 1972, 11 ha of woodland, heathland and previously manured pasture was fenced in for a sheep-grazing experiment. The different grazing intensities in the grassland area were quantified, since it is considered a prerequisite for the establishment of heterogeneous vegetation patterns, i.e. closely grazed areas, roughness and shrub. (2) Grazing intensity, implying associated effects of treading and dunging (occupancy), can be estimated by dunging intensity. Grazing intensity implying the defoliation by animals can be estimated using exclusion cages. Despite the fact that both methods show a degree of inaccurancy they seem appropriate for nature conservation purposes. (3) Peak standing crop (including standing dead material, but excluding litter) reached 210 g m-2 in Leontodon autumnalis, 420 g m-2 in Holcus lanatus, 510 g m-2 in Agrostis capillaris, 730 g m-2 in Agrostis stolonifera, 830 g m-2 in Juncus acutiflorus, and 1130 g m-1 in Juncus effusus communities in October 1981. (4) Grazing intensity expressed as efficiency of foraging was 0.89 in Leontodon autumnalis, 0.30 in Holcus lanatus and 0-09 in Agrostis capillaris communities over a 6 month period from June to November 1981. (5) Low species diversity was related to very low efficiency of foraging, whereas species diversity was relatively high for foraging efficiencies ranging from moderate to high. (6) Grazing at an average stocking of 3 sheep ha-' resulted in a smaller area (13%) with a short turf ( 36 cm), and a much larger area (69%) with intermediate turf. (7) Measurements of foraging efficiency can enhance the ideal situation in which authorities in charge of management, knowing the herbage accumulation, could indicate preferred proportion of structural components and then determine the appropriate stocking density.

Effect of time of spraying of glyphosate on the vegetation of an upland deep peat soil

AbstractThe vegetation of an upland deep peat soil consisting mainly of Festuca rubra, Holcus mollis, Molinia caerulea, Juncus acutiflorus and Potentilla erecta was sprayed with 1·5 kg a.i. per ha glyphosate applied to separate plots at monthly intervals from April to August. In July of the following year, April and May applications showed no effect on sward composition while June, July and August treatments resulted in increasing proportions of mosses and bare ground. August spraying gave almost complete control of the indigenous species with the exception of F. rubra and mosses. The results are discussed in relation to the establishment of improved pastures in upland areas by surface seeding.

Seasonal variation in in vitro digestibility and structural carbohydrate content of some commonly grazed plants of blanket bog

AbstractOven‐ and freeze‐dried samples of the separated green material of Trichophorum caespitosum, Molinia caerulea, Eriophorum vaginatum, Erio‐phorum angustifolium, Juncus acutiflorus and J. squarrosus collected in May, July and September were analysed for dry matter digestibility (DMD) using an in vitro procedure and for structural carbohydrate content.Results were affected by method of drying, oven‐dried (45°C) samples in general giving lower estimates of quality than freeze‐dried samples. Low DMD values were obtained for J. squarrosus for all sampling dates. The remaining species had DMD values above 60 in May; some maintained these levels until July but all had low values by September.A comparison was made between in vitro DMD and predicted DMD using the data from the structural carbohydrate analyses and the summative equation of Van Soest (1965a). Two species, J. acutiflorus and J. squarrosus, showed poor agreement between values obtained by the two methods. The other species showed good agreement between values in May and July but poor agreement in September.The data are discussed in relation to the quality and seasonal patterns of growth of species of hill vegetation.

A Preliminary Survey of Soil Aeration Conditions in a Scottish Hill Grazing

In a previous communication (Poel 1960) an instrument for the estimation of oxygen diffusion rates in soils in situ was described and data were given suggesting that the meter readings provide a good estimate of aeration status at the soil-root interface. The present paper concerns estimations of oxygen diffusion rate and soil pH made during the summer of 1958 at Ballochraggan, Port of Menteith, Perthshire, a hill grazing which was formerly the Bracken Eradication Experimental Station of the West of Scotland Agricultural College. Ballochraggan occupies an area of 413 acres (167 ha) ascending northwards from the Stirling-Aberfoyle road at 148 ft (45 m) above sea level to the crest of the Menteith Hills, an altitude of 1150 ft (351 m). At approximately the 700 ft (213 m) contour, there is a grassy ridge or 'drum'. Below the drum, the vegetation is mainly composed of Agrostis-Festuca grassland with Pteridium, together with numerous 'flushes' dominated by Juncus acutiflorus. Areas of Holcetum mollis, Juncetum effusi and Molinia-Nardus vegetation also occur. On the north side of the drum, the land falls to a plateau averaging 600 ft (183 m) altitude. This region is locally dominated by Pteridium, Pteridium in AgrostidoFestucetum, and Calluna. In the lower-lying parts, Eriophoretum vaginati is found, especially towards the east, while in the west, Juncus acutiflorus flushes occur. The area up to and including the plateau was mapped in detail to a scale of tin. (2-5 mm) to 10 ft (3 m) between 1943 and 1947 (Poel 1949). The large scale of the map and the fact that landmarks such as large rocks, boulders and trees were included, enables the site of any observation or estimation to be recorded precisely and to be readily located in the future. Thus the sites of all the estimations reported in the present paper are known and can be reinvestigated at any time in the light of changes in vegetation and drainage conditions.