Hippuris Vulgaris Research Articles

A further Contribution to the Flora of Jammu and Kashmir State

The paper describes the salient features of the vegetation of the Siwalik range, the Chenab valley, the high uplands of Batote, Kistawar and Bhadrawah of Jammu province, the Pir Panjal range, Lolab valley and the mountain spurs of north-eastern portion of Kashmir province. A systematic census of 687 species of which 660 are Angiosperms, 6 are Gymnosperms and 21 are Pridophytes is included in the paper.Among plants of interest collected were two endemic species, viz., Viola falconeri Hook. f. & Thoms and Hedysarum cachemirianum Benth., seven new records, viz., Onopordon acanthium L., Callianthemum rutaefolium C. A. Mey., Enhydra fluctuans Lour., Merendera persica Boiss., Luzula pallescens (Wg.) Bess., Asperula odorata L., and Conrum maculatum L. and new areas of distribution for Thesium himalense Royle, Hippuris vulgaris L., Menyanthes trifoliata L., and Lathraea squamaria L. which are previously unrecorded in the published literature on the flora of this area.

New data on chromosome numbers of aquatic of Yakutia

Chromosome count data (2n) for 6 species of aquatic and semi-aquatic species from 11 localities are given: Callitriche hermaphroditica 2n = 6, Hippuris vulgaris 2n = 32, Potamogeton berchtoldii 2n = 26, Ranunculus subrigidus 2n = 16, R. trichophyllus 2n = 32, Sagittaria natans 2n = 22. For counting, both materials fixed in the field and seedlings grown in laboratory conditions (species of Ranunculus, section Batrachium) were used. The optimal fixation time for seedlings of Ranunculus spp. for counting the number of chromosomes is 9-10 a.m. The numbers of chromosomes for Potamogeton berchtoldii and Sagittaria natans were found for the first time in Yakutia.

Aquatic flora of the high-mountain lakes in the southeastern part of the Chersky Ridge within the basin of the upper Kolyma River

We investigated several intermountain depressions in lakes with diverse flora of aquatic vascular plants in the southeastern part of the Chersky Range. The study area was located between 63–64° N and 147–148.5° E, at approximately 800–1200 m a.s.l. We identified 48 species and three hybrids.Among them, the families Potamogetonaceae (13 species and 1 hybrid) and Ranunculaceae (7 species) were characterized by the greatest diversity. For the first time, Stuckenia subretusa was found in the Magadan Region, which is the southernmost locality for this species. In an ultracontinental climate with an average annual air temperature of –13.1 °С, Arctophila fulva, Eleocharis acicularis, Hippuris vulgaris, Potamogeton alpinus, Ranunculus gmelinii, R. reptans and Sparganium hyperboreum are widespread. The species composition of aquatic plants is most diverse in small lakes at altitudes of 750–850 m a.s.l. in the plain interfluve, where the rarest species in the Kolyma River Basin are found. At altitudes above 850 m a.s.l. the most diverse species were found in the smallest lakes located near the large lakes. Obligate aquatic plants (80 %; 41 taxa; 30 hydrophytes and 11 hydrohygrophytes) dominated the flora of the mountain lakes. Only 20 % (10 species) of the flora were represented by plants of excessively moist coastal habitats. Among the 30 hydrophyte taxa 11 species grew up to 1050 m a.s.l. and 19 species grew at 950 m a.s.l. We identified four species that were protected at the regional level. Stuckenia pectinata is included in the Red Book of the Magadan Region, and Isoёtes asiatica, Nuphar pumila and Subularia aquatica are included in the Red Books of the Magadan Region and the Republic of Sakha (Yakutia).

Terrestrial vegetation and lake aquatic community diversity under climate change during the mid–late Holocene in the Altai Mountains

Using pollen analysis and metabarcoding of plant sedimentary ancient DNA (sedaDNa), we infer the floristic diversity in the vicinity of Lake Balyktukel, Ulagan Plateau, the Altai Mountains, over the last 7 kyr. The SedaDNA method identified 200% more taxa than found by morphological pollen analysis. In particular, it revealed that the dominant tree for the last 7 kyr was Larix rather than Pinus, which was less frequent in the vicinity of Lake Balyktukel. About 7 ka, larch forest mixed with dwarf birch was widespread on the Ulagan Plateau. The period between 5.3 and 3.4 kyr BP was characterized by the maximal spread of larch forest with an understorey cover of Vaccinium vitis-idaea. Pollen-based annual precipitation reconstruction indicates the most humid phase was between 6.95 and 4.3 ka, and generally coincides with maximal phytodiversity. The most bioproductive period of the lake was from 7 to 6 ka. After that, the trophicity of the lake decreased until 4.5 ka. The appearance of Hippuris vulgaris and increase in Ranunculus subgen. Batrachium at about 5.3–5 ka may indicate the extension of shallow-water ecotopes. Between 3.7 and 3.5 ka, the cyanobacterium Anabaena – an indicator of increased organic matter and algal blooms – was widespread. A planktic thermophilic cladoceran Bosmina longirostris appeared after 1.8 ka and colonized the lake, suggesting an increase in lake trophicity. The last 100 years have been characterized by dramatic changes in the cladoceran community reflecting significant warming of climate.

Hippuris vulgaris could replace Myriophyllum aquaticum for efficiently removing water phosphorus under low temperature conditions in China

Phytoremediation is widely used for the restoration of aquatic environments. However, the phytoremediation effects and mechanisms of special submerged species of native aquatic plants, especially under low-temperature conditions, are not yet clear. In this study, two typical submerged plants, Myriophyllum aquaticum (M. aquaticum; an exotic species) and Hippuris vulgaris (H. vulgaris; a native species), in China were investigated for their phosphorus (P) removal efficiencies (REp) and the related mechanisms of phytophysiology and microorganisms in a low-temperature incubator (10 °C during the day and 2 °C at night). At an initial P level of 0.5 mg L−1, the two plants exhibited similar REp, with the highest values (73.5%–92.1%) observed on days 3–6. After 18 days, the residual P concentration in the water was less than the Grade III limit value (0.2 mg L−1; GB 3838–2002). However, M. aquaticum had a faster REp velocity than H. vulgaris at an initial P level of 3.0 mg L−1, which was attributed to the mechanisms of plant and its interactions with microorganisms. Compared to the control group, the superoxide dismutase activity of H. vulgaris was significantly increased and its catalase activity was decreased, whereas for that of M. aquaticum was the opposite. Micro region X-ray fluorescence analysis revealed that there may be synergic absorption effects between P, S, and K, and antagonistic absorption action between P and Mn in H. vulgaris. In addition, Acinetobacter, Novosphingobium and Pseudomonas were enriched at 3.0 mg L−1 P level with these two plants, but Chlorophyta only accumulated with H. vulgaris, respectively. Overall, the native species, H. vulgaris, could replace the exotic M. aquaticum to efficiently remove P from polluted water at low temperatures. These findings provide a theoretical foundation for submerged plants P removal capabilities, and the protection of local ecosystem diversity at low temperatures.

Improving earthworm quality and complex metal removal from water by adding aquatic plant residues to cattle manure.

Vermicomposting is an economical and environmentally friendly process. However, related knowledge of vermicomposting aquatic plant residues (APRs), earthworm quality, and mechanisms for metal removal from water is still lacking. Nelumbo and Oenanthe javanica residues and their mixture were treated with Eisenia foetida and cattle manure for 45 days. Compared with the control comprising only cattle manure, addition of the APR mixture improved earthworm quality, mainly for low crude ash, high alkaloid compounds and different fat compositions in the Nelumbo residue and the balanced protein proportion of the APR mixture. All the vermicompost especial O. javanica residue added (VO) played efficient roles in removing metals from water initially containing 2.0mg Cu L-1 and 8.0mg Zn L-1. There were higher removal efficiencies (Ers) at the dosage of 4gL-1 with a small microbial contribution. VO significantly increased Ers, which could be from the decrease of phylum Firmicutes (especial Bacteroides) abundance, stronger CH2, C =O, and CH, the addition of COOH groups, and higher organic matter and total phosphorus contents. The combination of VO and Hippuris vulgaris was optimized as an ecological and economical method for treating complex-metal polluted water. Moreover, our study widened the route for APR reuse.

Late Glacial development of lakes and wetland vegetation in a dune area in Central Poland

This study investigated the history of the development of six, paleo-lakes, which are at present filled with sediments, in a dune area in Central Poland, based on multiproxy paleoecological analyses and accelerator mass spectrometry radiocarbon dating. The aims of the paleoecological studies were: i) to determine the initial age of lakes development, ii) to reconstruct the local and regional plant succession, as well as iii) to reconstruct the environmental conditions during the initial stage of the development of lakes and peatlands. The obtained results indicated that: the former lakes in dune depressions were developed during the Bølling and Allerød when sparse vegetation allowed strong aeolian activity. Climate warming in Bølling led to the development of a denser plant cover, inhibition of sand transportation and the formation of mid-dune reservoirs with the accumulation of organic sediments. As indicated by 14C dating, mid-dunes basins were formed between 14 686 ± 60 cal. yr BP and 13 421 ± 60 cal. yr BP. The results of the paleobotanical analysis suggested that the reservoirs were shallow, oligo-mesotrophic, inhabited by pioneer calcicole vascular plant species such as: Chara sp., Hippuris vulgaris, Potamogeton natans, Potamogeton fresii, Potamogeton alpinus and Potamogeton filiformis, and mosses such as: Pseudocalliergon trifarium, Calliergon sp. and Calliergonella cordifolium. The area next to the reservoirs was covered with sparse pine forests combined with birch, which is typical of the Late Glacial period. The open areas were dominated by psammophilic and steppe vegetation, including Poaceae, Artemisia and Hippophae rhamnoides. Geochemical analysis revealed that Ca2+ and Fe3+ were in high concentrations, which could have influenced the presence of taxa preferring soil with high Ca2+ content. The accumulation of calcium in sediments confirms that the reservoirs were fed by groundwater originating from the progressive degradation of permafrost associated with thermal changes.

Clear phylogeographical structures shed light on the origin and dispersal of the aquatic boreal plant Hippuris vulgaris.

Aquatic plants are an important ecological group in the arctic flora; however, their evolutionary histories remain largely unknown. In order to deepen our understanding of the evolution of these plants, we explored the phylogeographical structure of an aquatic boreal plant Hippuris vulgaris in a broad geographical sampling from Eurasia and North America using the chloroplast intergenic spacer psbA-trnH and seven nuclear microsatellite loci. Two closely-related species H. lanceolata and H. tetraphylla were also included because of their taxonomic controversy. Both chloroplast DNA sequences and nuclear microsatellite data revealed three genetic lineages with distinct distribution ranges. Incongruence between nuclear and chloroplast DNA lineages occurred in 14 samples from Russian Far East and Europe caused by inter-lineage hybridization. No private haplotypes or independent genetic clusters were evident in H. lanceolata or H. tetraphylla, suggesting that these two species should be considered conspecific ecotypes of H. vulgaris. Analysis using Approximate Bayesian Computation-Random Forest approach suggests that Hippuris vulgaris originated in China, followed by dispersal into Russia plus Northeast China, then successively westwards into Europe and North America, and finally into the Russian Far East from both North America and Russia plus Northeast China. This study is the first to elucidate the historical dispersal processes of a circumarctic aquatic plant across the entirety of its range.

Effects of highland environments on clonal diversity in aquatic plants: An interspecific comparison study on the Qinghai-Tibetan Plateau.

Clonal reproduction is one of the most distinctive characteristics of plants and is common and diverse in aquatic macrophytes. The balance between sexual and asexual reproduction is affected by various conditions, especially adverse environments. However, we know little about clonal diversity of aquatic plants under suboptimal conditions, such as at high altitudes, and having this information would help us understand how environmental gradients influence patterns of clonal and genetic variation in freshwater species. The microsatellite data of four aquatic taxa in our previous studies were revisited to estimate clonal and genetic diversity on the Qinghai-Tibetan Plateau. Clonal diversity among different genetic groups was compared. Local environmental features were surveyed. Beta regressions were used to identify the environmental factors that significantly explained clonal diversity for relative taxon. The level of clonal diversity from high to low was Stuckenia filiformis > Hippuris vulgaris > Myriophyllum species > Ranunculus section Batrachium species. A positive correlation between clonal and genetic diversity was identified for all taxa, except H. vulgaris. Clonal diversity was affected by climate in S. filiformis and by the local environment in H. vulgaris. For Myriophyllum spp., low elevation and high sediment nutrition were significant for sexual recruitment. The environmental effects on clonal diversity were not significant in R. sect. Batrachium spp. Clonal diversity of aquatic plants is moderate to high and varies greatly in highlands. The effects of breeding systems and environmental factors on the patterns of clonal variation were identified. Elevational gradients, climates and local conditions play different roles in clonal diversity among relative taxon. Our results highlight the importance of sexual recruitment in alpine aquatic plant populations and the influence of environmental factors on the genetic patterns in freshwater species at local and regional scales.

Colletotrichum litangense sp. nov., Isolated as an Endophyte of Hippuris vulgaris, an Aquatic Plant in Sichuan, China.

An unknown endophytic fungus was isolated from the aquatic plant Hippuris vulgaris in Litang county, Sichuan province, China. Phylogenetic analyses inferred from combined ITS, Sod2, Apn2, and TUB2 sequences revealed that the endophyte is a new species belonging to the Colletotrichum graminicola species complex. Morphological characteristics showed that Colletotrichum litangense is characterized by its falcate, lunate to sublunate conidia, and ellipsoidal, ovoid, or lobed appressoria. Pathogenicity tests on several fruits showed that C. litangense could induce anthracnose lesions. As a result of the phylogenetic, morphological, and pathogenicity analyses, we proposed the name Colletotrichum litangense for the new species.

Removal effects of a biomass bottom ash composite on tailwater phosphate and its application in a rural sewage treatment plant

Tailwater phosphate from sewage treatment plants and biomass bottom ash (BA) from power plants has become a global concern for the sustainable environmental development and resource management. However, there are large gaps in the understanding of the removal mechanisms and application conditions of BA on tailwater phosphate. In this study, the removal effect and mechanism of BA and its composites were fully discussed using a series of experiments, including adsorption, desorption, characterization, and incubation experiments. It was found that the combination of BA and red soil at a rate of 4:1 (CBA) could remove 92.44% of phosphate from tailwater in 3–10 h. Its adsorption process was well fitted by the pseudo-second-order kinetic and Freundlich isotherm adsorption models. The mechanism of phosphate adsorption primarily included ligand exchange, physical adsorption, chemical precipitation, electrostatic attraction, and ion exchange. The CBA could be used as a better substrate for constructed wetlands because it was effective under wide application conditions, which varying pH values (4.0–8.0), initial concentrations of tailwater phosphate (0.5–5.0 mg L−1), and even extreme temperatures (heat and cold). Moreover, Hippuris vulgaris L. was optimized and combined with the CBA to deeply remove 57.45–76.06% of phosphate from a rural sewage treatment plant. The phosphate concentration after treatment could reach below the limit values of the Grade III or IV standard (GB 3838–2002), though the CBA contained and released phosphate. This study can help provide a recycling route for both BA and tailwater phosphate resources, extend the industrial chain of biomass power plants, and improve the surrounding water environment.

ПОЛИПЛОИДИЯ У ВОДНЫХ И ПРИБРЕЖНО-ВОДНЫХ СОСУДИСТЫХ РАСТЕНИЙ СЕВЕРО-ВОСТОКА АЗИИ

The chromosome numbers of aquatic and semiaquatic vascular plants growing in extreme North-East Asia, east of the Lena River, were analyzed. We have reviewed the information about the karyological peculiarity of the aquatic flora based on published data, including our own definitions. The karyological data are considered depending on the taxonomic position, distribution and ecological characteristics of the species. The chromosome numbers are known for 119 out of 123 species. There is no data on Zannichellia komarovii, Eleocharis termale, Stuckenia subretusa and Potamogeton sibiricus. In the aquatic flora of North-East Asia, the proportion of polyploids is higher (79%) than that reported for the entire Beringian flora (69%). We analyzed species for the presence of polyploidy depending on the type of area. Analysis by latitudinal groups revealed that all Arctic and hypoarctic species of aquatic plants are polyploids. The minimum proportion of polyploids is observed among arctoboreal species. Analysis by longitudinal groups revealed that the lowest proportion of polyploids was noted among species found only in Eurasia and absent in North America (61%), and it was the highest among pluriregional species (96%). The species of the families Cyperaceae, Lemnaceae, Ranunculaceae and Poaceae are characterized by a high level of variability in the number of chromosomes. The greatest variety of chromosome numbers is observed in the polymorphic species Caltha palustris s. l., Agrostis stolonifera, Dupontia fisheri s. l., Phragmites australis, in all species of the genus Eleocharis, and in Nymphaea tetragona, Acorus calamus, Calla palustris. The isolated cases of a high level of ploidy were found in the extreme northeast, at the northern borders of ranges, in 3 species - Hippuris vulgaris, Arctophila fulva and Beckmannia syzigachne. Only diploids are known in the families Equisetaceae, Typhaceae, Zosteraceae from the flora of North East Asia. We revealed the existence of several chromosomal races in Ranunculus gmelinii and Caltha palustris (Ranunculaceae) in the Magadan region; the distribution of chromosomal races is partly related to geographic location and partly to plant habitats. Rare karyotypes in these species are observed in aquatic forms with mainly vegetative reproduction, growing in non-freezing watercourses.

The evolutionary history and phylogeographic pattern of Hippuris vulgaris: hybridization and long-distance dispersal from China

Hippuris vulgaris is a widespread aquatic plant in the Northern Hemisphere. Phylogenetic analysis on a low-copy nuclear gene (PHYB) indicated that this species originated from a hybridization between two unknown ancestral parents. Two distinct lineages (I and II) were detected using chloroplast intergenic regions, and their divergence time was 1.51 Ma. Lineage I was composed of the populations from North China, Qinghai-Tibetan Plateau (QTP), and Europe while lineage II included the populations from North China, Europe and Japan. Based on the results of the Bayesian binary MCMC (BBM) analysis, QTP was likely the original center of these two lineages. The possible dispersal route for lineage I was inferred to be directly from QTP to North China and Europe, respectively, while lineage II likely dispersed first to Japan and from there moved separately to North China and Europe. In this study, we illustrate two important evolutionary events of H. vulgaris: hybridization and long-distance dispersals.

The complete chloroplast genome of Hippuris vulgaris (Plantaginaceae)

Hippuris vulgaris is an aquatic perennial herb distributed worldwide. In this research, the complete chloroplast genome of H. vulgaris was sequenced and assembled. Its complete genome size was 152,698 bp in length. The typical quadripartite structure was shown, which contained a large single-copy region (82,940 bp), a small single-copy region (18,262 bp), and a pair of inverted repeat regions (25,748 bp). The CG content of this genome was 37.6%. A total of 114 genes have been identified in the genome, including 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. In addition, 18 genes possessed at least one intron. The phylogenetic analysis indicated that H. vulgaris was nested in Plantaginaceae with 100% bootstrap value and was a sister to Digitalis, Plantago, Hemiphragma, Veronica and Veronicastrum.

The complete chloroplast genome sequences of Hippuris vulgaris (Plantaginaceae)

Two complete chloroplast genomes of Hippuris vulgaris (H. vulgaris_A and H. vulgaris_B), representing two distinct clades in China, were sequenced and assembled in this study. The circular genomes were 152,763 and 152,713 bp in length and exhibit a typical quadripartite structure of the large single-copy (LSC, 82,983/82,949 bp) and small single-copy (SSC, 18,294/18,278 bp) regions, separated by a pair of inverted repeats (IRs, both 25,743 bp). Both two cp genomes identically contain 133 genes, including 88 protein-coding genes, 37 tRNA, and eight rRNA genes. The phylogenetic analysis within Plantaginaceae demonstrated Hippuris an independent clade included in the expanded Plantaginaceae.

Biogeochemistry of macrophytes, sediments and porewaters in thermokarst lakes of permafrost peatlands, western Siberia

The chemical composition of thermokarst lake ecosystem components is a crucial indicator of current climate change and permafrost thaw. Despite high importance of macrophytes in shallow permafrost thaw lakes for control of major and trace nutrients in lake water, the trace element (TE) partitioning between macrophytes and lake water and sediments in the permafrost regions remains virtually unknown. Here we sampled dominant macrophytes in thermokarst lakes of discontinuous and continuous permafrost zones in the Western Siberia Lowland (WSL) and measured major and trace elements in plant biomass, lake water, lake sediments and sediment porewater. All six plant species (Hippuris vulgaris L., Glyceria maxima (Hartm.) Holmb., Comarum palustre L., Ranunculus spitzbergensis Hadac, Carex aquatilis Wahlenb s. str., Menyanthes trifoliata L.) sizably accumulated macronutrients (Na, Mg, Ca), micronutrients (B, Mo, Nu, Cu, Zn, Co) and toxicants (As, Cd). Accumulation of other trace elements, including rare earth elements (REE), in macrophytes relative to pore waters and sediments was highly variable among species. Using miltiparametric statistics, we described the behavior of ТЕ across two permafrost zones and identified several group of elements depending on their sources in the lake ecosystems and their affinity to sediments and macrophytes. Under future climate warming and shifting the permafrost border to the north, we anticipate an increasing uptake of heavy metals and lithogenic low mobile elements such as Ti, Al, Cr, As, Cu, Fe, Ni, Ga, Zr, and REEs by macrophytes in the discontinuous permafrost zone and Ba, Zn, Pb and Cd in the continuous permafrost zone. This may eventually diminish transport of metal micronutrients and geochemical tracers from soils to lakes and rivers and further to the Arctic Ocean.

Relationship Between Diversity of Aquatic Plant Communities and Water Environmental Factors in Lhalu Wetland

Plant diversity plays an important role in the integrity and stability of wetland ecosystems. Lhalu Wetland is the highest wetland in the world and is the largest urban natural swamp in China. It plays an important role in ecological balance, increasing air humidity, improving the urban climate, and purifying the water environment in Lhasa. The changes in plant diversity in different areas of the Lhalu Wetland and its relationship with water environmental factors were analyzed via field investigation, field monitoring, and indoor analysis. Results showed that 18 species of aquatic plants were found in the Lhalu Wetland. The Margalef species richness index was in the order M (Middle west) > W (West) > E (East) > N (North) > S (South). Index of species richness ranked of W (11), M (11) > N (8) > E (7) > S (6). Index of ShannonWiener followed that of M (1.9) > W (1.89) > S (1.63) > E (1.26) > N(1.18). Index of Simpson ranked of N (0.44) > E (0.34) > M (0.24) > S (0.21) > W (0.18). The order of Pielou index was that of S (0.91) > M(0.79) > W(0.78) > E(0.65) > N(0.56). Redundancy analysis showed that the diversity of aquatic plants in the Lhalu Wetland was affected by dissolved oxygen, pH, water temperature, total nitrogen, and turbidity. The dominant species in the Lhalu Wetland are CeratopHyllum demersum L., Hippuris vulgaris, Polygonum hydropiper, Softstem bulrush, Acorus calamus, and Juncus effusus, which show a trend of non-pollution-resistant species succession to pollution-resistant species.

Biological and geochemical indicators of climatic oscillations during the Last Glacial Termination, the Kaniewo palaeolake (Central Poland)

• Bølling-Allerød complex shows climatic heterogeneity and includes cold events. • Deglaciation passed 3 cold (GS-2a, GI-1d, GS-1) and 2 warm periods (GI-1e, GI-1a-c) • Traces of cold oscillation (GI-1b) within the Allerød were found. This study presents the results and interpretations of biological (floral and faunal) and geochemical (isotopic and chemical element composition) investigations of the Late Glacial and Holocene sediment accumulated in the Kaniewo palaeolake. These data allowed us to determine the indicators of environmental changes in this lake ecosystem, such as zooplankton and vegetation development, trophic state, water temperature, and water level. We documented the three cold periods (Oldest, Older, and Younger Dryas) separated by two warm periods (Bølling, Allerød). Additionally, we found traces of cold oscillations within the Allerød, lasting approximately 150 years, probably the Intra-Allerød-Gerzensee oscillation, recorded in western and southern Europe. Our data show that sediment accumulation began at the end of the Oldest Dryas period before ca. 13,900 yr cal BP. The top of the studied sediments represented the transition from the Late Glacial to the early Holocene (Preboreal period, ca.10,500 yr cal BP). The lithology of the sediments changed from silty sands at the bottom, then calcareous detritus gyttja partially interbedded by lake marl to peat at the top. Organic matter occurring in the deposits reflects algae and terrestrial sources. In the cold periods, small number of both Cladocera individuals and species (e.g. Bosmina (E.) longispina , Chydorus sphaericus , Alona affinis ), corroborate the unfavourable conditions for the development of zooplankton. Cladocera species indicated the initial oligotrophic status of the lake and the subsequent increase in trophic status. Plant and animal macrofossils indicate initial shallow lake ecosystem. Chara meadow developed at the bottom of the lake with a belt of vascular plants ( Carex sp., Hippuris vulgaris , Scirpus sp . ) in the littoral zone of the lake. Rich shallow vegetation was accompanied by animals, such as Mollusca (e.g. Valvata piscinalis, Pisidium obtusale, Bithynia tentaculata ) and Oribatidae sp., Cristatella mucedo , and Plumatella type.

Molecular characterization of Alfalfa mosaic virus (AMV) isolates in alfalfa and other plant species in different regions in Saudi Arabia

In a survey conducted in 2012 and 2013, 1166 samples from alfalfa plants and 202 samples from symptomatic weeds and cultivated plants growing adjacent to alfalfa fields were collected. Using DAS-ELISA, Alfalfa mosaic virus (AMV) was detected in 58.4% of the alfalfa samples and in 63.9% of the weeds and cultivated plants samples. ELISA detection of AMV was confirmed by testing representative samples from all regions by RT-PCR using a pair of primers (AMV/F and AMV/R) specific to the AMV coat protein (CP) gene. The size of the major product obtained from AMV-infected plants was identical to the 700 bp size expected from the CP gene of AMV. The amino acids and the nucleotide sequences of 17 Saudi AMV isolates from alfalfa, and 16 from other cultivated plants and weeds detected in different regions in Saudi Arabia showed a percentage of similarity that ranged between 87.9%–100% among them and 86.2% - 100% when compared with sequences of 15 different AMV isolates reported in the GenBank. This is the first time AMV was detected in Vigna unguiculata and in the following weed plant species: Chenopodium quinoa, Convolvulus arvensis, Malva parviflora, Hibiscus spp., Hippuris vulgaris, Cichorium intybus, and Flaveria trinervia in Saudi Arabia.

Accumulation of heavy metals in aquatic vegetation of the Barguzin River

This study is devoted to the analysis of the distribution of heavy metals in the aquatic system of the Barguzin River. This is one of the largest rivers of the Baikal lake system. The element composition of the aerial scion of Potamogeton pectinatus L. (syn. Stukenia pectinata (L.) Borner), Potamogeton perfoliatus L., Hippuris vulgaris L. and Nymphoides peltata (S.G. Gmelin) O. Kuntze of the Barguzin River is studied in this research. One of the main results of the study is the establishment of the following sequence of the accumulation of metals in aquatic plants: Mn > Fe > Сu (Zn) > Сr > Ni > Сo > Pb > Cd > Hg. Hippuris vulgaris L. contains the highest concentration of the studied metals. Thus, this research provides one of the important steps for the development of regional environmental standards and environmental risk assessments.