Limosella Aquatica Research Articles

Molecular evidence for hybridization in the aquatic plant Limosella on sub-Antarctic Marion Island

AbstractDNA sequence data have become a crucial tool in assessing the relationship between morphological variation and genetic and taxonomic groups, including in the Antarctic biota. Morphologically distinct populations of submersed aquatic vascular plants were observed on sub-Antarctic Marion Island, potentially representing the two species of such plants listed in the island's flora, Limosella australis R.Br. (Scrophulariaceae) and Ranunculus moseleyi Hook.f. (Ranunculaceae). To confirm their taxonomic identity, we sequenced a nuclear locus (internal transcribed spacer; ITS) and two plastid loci (trnL-trnF, rps16) from three specimens collected on Marion Island and compared the sequences with those in public sequence databases. For all three loci, sequences from the Marion Island specimens were nearly identical despite morphological dissimilarity, and phylogenetic analyses resolved them to a position in Limosella. In phylogenetic trees and comparisons of species-specific sequence polymorphisms, the Marion Island specimens were closest to a clade comprising Limosella aquatica L., L. curdieana F.Muell. and L. major Diels for ITS and closest to L. australis for the plastid loci. Cytonuclear discordance suggests a history of hybridization or introgression, which may have consequences for morphological variability and ecological adaptation.

A monopodial rosette model of shoot formation as a program of secondary-aquatic grasses appearing

On the basis of comparative morphological analysis of the structure of life forms the concept “key biomorph” is offered; it is a mien of a plant which reflects adaptation to the conditions of a definite habitat (a static aspect, a model) and a definite stage in evolutional changes of biomorphs (a dynamical / evolutional aspect). The paper shows a comparative morphological range of key biomorphs in accordance with a monopodial rosette model of shoot formation per gradient of moisture increase in the direction: a floodplain meadow – shores, shore fronts – the water line – a water body. Polygonum bistorta is considered the original key biomorph, changes in it could occur in three lines: 1) Polygonum bistorta – Butomus umbellatus – Nuphar lutea; 2) Polygonum bistorta – Scirpus lacustris – Eleocharis palustris; 3) Polygonum bistorta – Limosella aquatica – Stratiotes aloides. It seems that appearing of secondary-aquatic grasses with a monopodial rosette model of shoot formation was provided by the following modes of morphological evolution: deviation on the shoot level; abbreviation of the bud stage in shoot formation, in forming a part of the shoot (inflorescence), in the anatomic structure of the shoot and the ontogenesis of the original plant; prolongation of the bud phase in shoot development and ontogenesis of the genet.

Biomorph Limosella aquatica L. and its contribution in stolon-rosette water grasses formation

The paper presents comparative-morphological analysis of biomorphs Limosella aquatica L., stolon-rosette perennial mesophyte grasses (Viola odorata L.), and yearling vegetative hydrophytes (Stratiotes aloides L. and Hydrocharis morsus-ranae L.). It is shown that L. aquatica is a monopodial growing monocarpic with side stolon-rosette shoots and their systems with up to four branching orders. The primary shoot, as well as rosette parts of stolon-rosette shoots, is made of metamers with foliage leafs, axil complexes with differently sets of constituents: two collateral buds and/or their derivatives: flower buds/flowers/fruit, side stolon-rosette shoots or their systems. At the initial stage the shoot-forming mode of L. aquatica is similar to that of V. odorata: a monopodial rosette one with green assimilating leaves, flowers, and stolon-rosette shoots. But iterative branching of stolon-rosette shoots changes the shoot-forming mode of L. aquatica to a sympodial semirosette as in S. aloides, and especially in H. morsus-ranae. Biomorph L. aquatica combines the features of stolon-rosette perennial mesophyte grasses and stolon-rosette yearling vegetative hydrophytes: stolon-rosette shoot formation from axil buds, iterative branching, collateral buds, reduction inflorescence to one flower (S. aloides). Thus of habit L. aquatica can be viewed as a stage of perennial flower mesophyte plants’ shifting to life in water.

Растительность акватории и побережий озера Таловское и его окрестностей (Корякский округ, Камчатский край)

Растительность акватории и побережий озера Таловское и его окрестностей (Корякский округ, Камчатский край)

Effects of farming practice on populations of threatened amphibious plant species in temporarily flooded arable fields: implications for conservation management

Intensification of land use has led to a severe decline of arable plants in the past decades, particularly among species of marginal habitats, such as temporarily flooded fields. Few studies have focused on the factors controlling the population dynamics of these species, and on suitable strategies for more effective conservation. To investigate the effects of farming practice on plant populations of temporarily flooded fields, we determined above-ground and below-ground densities of four annuals (Elatine alsinastrum, Limosella aquatica, Myosurus minimus and Peplis portula) in a 3-year on-farm experiment. A fully-factorial experiment combined the treatments soil tillage, presence of crops, fertilisation and herbicide application. Soil tillage had a positive effect on plant establishment, whereas herbicide application had a negative effect on the establishment of all study species. Plant densities were controlled by application of fertilisers and herbicides, with the most significant effects on L. aquatica and M. minimus. Soil seed densities were mainly affected by environmental factors, but tillage also significantly reduced the seed densities of E. alsinastrum and P. portula. Other farming practices had a minor impact. Thus, reduced management can help in maintaining populations of rare amphibious plant species. The effect of different crops, crop rotation and the timing of management will help in developing the most appropriate management strategies for conservation of these plant species.

Restoration of Heterogeneous Disturbance Regimes for the Preservation of Endangered Species

Disturbance is a natural component of ecosystems. All species, including threatened and endangered species, evolved in the presence of, and are adapted to natural disturbance regimes that vary in the kind, frequency, severity, and duration of disturbance. We investigated the relationship between the level of visible soil disturbance and the density of four endangered plant species on U.S. Army training lands in the German state of Bavaria. Two species, gray hairgrass ( Corynephorus canescens ) and mudwort ( Limosella aquatica ), showed marked affinity for or dependency on high levels of recent soil disturbance. The density of fringed gentian ( Gentianella ciliata ) and shepherd’s cress ( Teesdalia nudicaulis ) declined with recent disturbance, but appeared to favor older disturbance which could not be quantified by the methods employed in this study. The study illustrates the need to restore and maintain disturbance regimes that are heterogeneous in terms of the intensity of and time since disturbance. Such a restoration strategy has the potential to favor plant species along the entire spectrum of ecological succession, thereby maximizing plant biodiversity and ecosystem stability.

Distribution of five rare plants in Korea

The natural habitats and distribution of five rare plants were recently discovered in Korea. Salomonia oblongifolia DC., which grows in mountain wetlands, was found in Gijang-gun, Busan, Gokseong-gun, Jeollanamdo, and Shinan-gun, Jeollanam-do. Glaux maritima var. obtusifolia Fernald, which grows along the coast, was found in Yangyang-gun, Gangwon-do, Pohang-si, Gyeongsangbuk-do and Buk-gu, Ulsan. Tillaea aquatica L. and Limosella aquatica L., which was previously not known to be present in Korea, were discovered in Gijanggun, Busan for the first time. Apocynum lancifolium Russanov, which has a narrow distribution range in Korea, was also found in Samcheok-si, Gangwon-do, Ansan-si, Gyeonggi-do, Siheung-si, Gyeonggi-do, Jung-gu, Incheon, Yeongdeok-gun, Gyeongsangbuk-do and Shinan-gun, Jeollanam-do.

Cytotoxic and antioxidant activities of selected Lamiales species from Mexico

Context: Methanol extracts obtained from eight species belonging to four families of the Lamiales order native to Mexico were investigated for biological action.Objective: Cytotoxicity and antioxidant activity of methanol extracts have been investigated.Materials and methods: Cytotoxic activity was evaluated by the sulphorhodamine B protein staining assay against KB (nasopharyngeal), HEp-2 (larynx), HF-6 (colon), MCF7 (breast), PC-3 (prostate), and Ca Ski (cervix) carcinoma cell lines. To analyze the antioxidant activity, common stable radicals chromogens, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS·+) and DPPH (1,1-diphenyl-2-picrylhydrazyl) were used. The ferric reducing antioxidant power (FRAP) and the total phenolic content of the samples were also determined.Results: Some of the extracts, such as Limosella aquatica L. (Scrophulariaceae), Mimulus glabratus Kunth. (Phrymaceae), Pedicularis mexicana Zucc. ex Benth. (Orobanchaceae), and Penstemon campanulatus (Cav.) Willd. (Plantaginaceae) displayed remarkably selective cytotoxic activity. However, the extract from Veronica americana (Raf.) Schwein (Plantaginaceae) showed the highest activity with IC50 values of 1.46 and 0.169 μg/mL on PC-3 and HF-6 cells, respectively. With the exception of M. glabratus, all the extracts showed different degrees of antioxidant activity with IC50 values from 0.89 up to 1.8 in the ABTS assay; from 0.49 up to 1.25 mg/mL in the DPPH assay and with the FRAP evaluation, 36 to 68 equivalents in mM of FeSO4. V. americana also showed the highest antoxidant activity with IC50 values from 0.491 and 0.892 mg/mL, on DPPH and ABTS assays, respectively.Discussion and conclusion: These findings demonstrated that the species studied have great potential cytotoxic and antioxidant activity.

BIODIVERSITY AND COMMUNITY ECOLOGY OF AQUATIC PLANT IN LAKE NAM CO, TIBETAN PLATEAU

The most crowded and highest lakes in the world distributes on the Tibetan Plateau,China.Lake Nam Co,in the North Tibet,is the highest great lake in the world,and is the second biggest salt water lake,only inferior to Lake Qinghai,in China.Biodiversity and community ecology of aquatic plant in this lake will have the impor-tant model and the demonstration significance to other lakes in the Tibetan Plateau. Aquatic plants mainly distributes in the eastern part of Lake Nam Co,and its characters of habitat are diverse,including small puddles,ponds,swamps,streams,as well as connected lakes.The results obtained from the pre-sent field study and literature survey showed that a total of 34 species belonging to 19 genera and 15 families,among which,1 species,1 genera and 1 families belonged to Charophyta,16 species,8 genera and 7 families be-longed to Monocotyledon,and 17 species,10 genera and 7 families belonged to Dicotyledon.Three new recorded families,including Characeae,Callitrichaceae and Scrophulariaceae,three new recorded genera and seven new recorded species were found in Lake Namco and its catchment.The dominant families of aquatic plants in this lake were Cyperaceae,Ranunculaceae,Potamogetonaceae and Haloragaceae.Among all families of aquatic plants,Potamogetonaceae and Cyperaceae included the maximum number of species,accounting for 26.47% and 20.59%,respectively.Potamogetonaceae,Ranunculaceae,Cyperaceae and Zannichelliaceae were most frequently occurring families and the frequently occurring genus included Potamogeton,Batrachium,Zannichellia and Carex.The dominant species in frequency included P.pectinatus,Z.palustris,B.bungei var.flavidum and B.Eradicatum and in biomass is P.pectinatus,Myriophyllum spicatum and B.bungei var.flavidum. According to the basis of community classification,there were eleven types of aquatic plant communities in Lake Nam Co in Lake Nam Co,including Ass P.pectinatus,Ass P.pectinatus + B.bungei var flavidum,Ass P.pectinatus + Z.palustris,Ass P.pectinatus + Chara braunii,Ass P.pectinatus + M.spicatum,Ass L.aquatica + B.Eradicatum,Ass M.spicatum + B.Eradicatum,Ass Limosella aquatica,Ass M.spicatum+ P.pectinatus + B.bungei var flavidum,Ass P.pectinatus + B.Eradicatum and Ass M.spicatum+ P.pectinatus + B.eradicatum.The flora of aquatic vascular plants in the Lake Nam Co was fundamentally north temperate in nature. The interspecific correlation coefficients exhibited by constellation diagram showed the significant associa-tions between the lake shore wetland species in Lake Nam Co,Tibetan,indicating a continuum of the species groups.Quadrats investigation indicated that these types of aquatic plant communities were mainly composed of submersed macrophyte communities with few floating-leaved macrophytes.β-diversity analyses suggested sig-nificant variations in species assembly among different quadrats along the environment gradient. Our research suggested that aquatic plants in the basin of Lake Nam Co possessed a wide range of ecological adaptation and niche separation,and played important roles in the linking of soil and water environment and in the maintenance of species diversity of land and water interface on the Tibetan Plateau.

Coleanthus subtilis (Tratt.) Seidel - a new species to the Polish vascular flora

The authors describe the locality of a so far in Poland unknown species <em>Coleanthus subtilis</em>. It was discovered on the Oleśnica Plateau near Wroclaw. This grass occurs on a surface of ca. 15 ha, round muddy shores of fishponds. The large stand makes the impression to be at least 50-year old. Together with the grass of our interest there grow also other, not frequent to day, species like <em>Veronica peregrina</em>, <em>Myosurus minimus </em>and <em>Limosella aquatica</em>. The traditional management of fishponds makes the basis of maintenance of all the species and the whole community. The constant filling with water of the reservoirs and application of fertilisers threatens the existence of the whole rare and interesting ecosystem.

Coleanthus subtilis (Poaceae), New to Northwest Territories, and Its Status in North America

A floristic survey of a polje lakebed, which is full in the spring but drains completely as the season progresses, revealed a community of small mud-bottom plants including the globally rare Coleanthus subtilis, not previously recorded from Northwest Territories, Canada. The newly discovered site is 1077 miles NNW of its nearest North American location in southern British Columbia, which is the northern edge of a region of occurrence including southern British Columbia and the Columbia River in Washington and Oregon. The lakebed flora included four zones of vascular plants. Coleanthus subtilis was confined to the lowest level mud-bottom community, which had been exposed for the shortest period and included a rich assemblage of annuals including Juncus bufonius, Limosella aquatica, and Ranunculus hyperboreus. The lakebed flora included mostly widespread boreal species, and C. subtilis may be included in this category. It appears restricted to specific montane and boreal areas by its requirement of pronounced seasonal inundation in a cool climate. Coleanthus subtilis may have persisted at the Washington and British Columbia locations, near the limit of the continuous montane glaciation, since early postglacial times. The occurrence in Northwest Territories may be either a result of dispersal from unglaciated areas of Beringia nearby to the west or from the south. Although it has sometimes been considered introduced in the United States parts of its North American range, it is here considered native at all of its North American sites on the basis of: (1) its restricted and unusual habitat; (2) global rarity; (3) suffusive rarity, which is known to lead to mistaken assumptions of introduction; (4) occurrence in botanically rich regions and close association with rare native species; (5) relatively early year of collection; (6) distribution corresponding to a well recognized native pattern; (7) lack of evidence of spread to anthropogenic habitats; and (8) the fact that it is easily overlooked by early collectors as a result of only appearing at intervals of several years when water levels have dropped sufficiently.

A NEW LOCATION OF TADPOLE SHRIMP (TRIOPS CANCRIFORMIS L.) IN LITHUANIA

Tadpole shrimps (Triops cancriformis L.) were registered on 10 August 2007 and during the repeated observation on 8 September 2007 (Fig. 1). Only two habitats of this species of triops are known to exist in Lithuania (Raðomavieius 2007). To date no records of T. cancriformis have been reported from the northern part of Lithuania (Raðomavieius 2007). The habitat of these rare crustaceans (Red Data Book of Lithuania category 2 (V), MoE 2007) has formed in quite an unexpected place – at the sodden edge of a rape field situated at a distance of 5.5 m from the carriageway side (Fig. 2). From the viewpoint of administrative division, the habitat of Triops cancriformis L. is in Pasvalys region, on the left side of the No. 150 motorway (Ðiauliai–Pakruojis–Pasvalys), 59.7 km from Ðiauliai. The nearest settlement Meðkalaukis lies 3.70 km south-west of the location. Coordinates of the location are 24°16'11.2'' east longitude and 56°01'53.0'' north latitude (error – 6 m). In the north of the habitat there is a 150 m wide tract of a rape field with a mediumaged mixed forest behind it. Approximately 50 m east of the habitat, there is a mature deciduous forest and a wheat field (Triticum sp. L.) to the south of it (on the other side of the above mentioned motorway). Suitable conditions for the development of T. cancriformis in the rape field formed for several reasons, water accumulation being of the primary importance. The location is situated in the lowland of central Lithuania, in a moderate descent of the flat landscape relief, just 41 m above sea level. However, the presumption that the habitat is supplied with groundwater has to be ruled out, for 45 m north-east of the site there is a ~10 m wide and ~5 m deep drain ditch which drains underground water. The only source of moisture for this temporary water body is precipitation. Thus, the second prerequisite for the formation of the T. cancriformis habitat comes out. It is specificity of soil. According to Miliauskas and Nedzinskas (2000), soils in these areas are periodically dry. Hence, soil moisture regime is mainly preconditioned by the amount of precipitation. Surface layers of carbonate-rich morenic clay loam and clay have formed a natural hydrological barrier (Galvydyte 2000). In 2007 the amount of precipitation was sufficient for the formation of a perennial puddle and develoment of T. cancriformis eggs. The fact that a number of water plants, plants of damp sites and algae managed to root and even to flourish there – some of them reaching generative and senile stages, proves that the terrain has been sodden for a long period of time (Vilkonis 2001). Among such plants the following should be mentioned: great reedmace (Typha latifolia L.), common reed-grass (Phragmites australis (Cav.) Trin. Ex Steud.), marsh woundwort (Stachys palustris L.), murr marigold (Bidens tripartita L.), marsh cranesbill (Geranium palustre L.), common water-plantain (Alisma plantagoaquatica L.), common mudwort (Limosella aquatica L.), muskgrasses (Chara sp.) (Gudþinskas 1999; Vilkonis 2001). The following water animals managed to inhabit the temporary water reservoir: pond scatter (Gerris sp.), great diving beetle (Dytiscus marginalis L.), and a lot of fire-bellied toads (Bombina bombina L.).

Find of association Cypero-Limoselletum (Oberd. 1957) Korneck 1960 (Isoёto-Nanojuncetea) in Magadan region, Russian Far East

Сommunities of the association Cypero-Limoselletum (Isoёto-Nanojuncetea) were found on soil roads of the second above-floodplain terrace in the upper Kolyma River valley. This fact substantially extends the area of association distribution within the Northern Eurasia. Four releves of the communities domi­nated or co-dominated by Eleocharis acicularis and Limosella aquatica are presented.

Aquatic macrophyte vegetation development in Krakenes Lake western Norway, during the late-glacial and early-Holocene

Macrofossil analyses were carried out on the late-glacial and early-Holocene sediments of the radiocarbon-dated master core at Krakenes Lake, western Norway, to investigate the aquatic vegetation changes. Ranunculus sect. Batrachium and Nitella were the earliest pioneers after deglaciation ca. 12,300 14C yr BP. The Allerod vegetational succession was very slow during ca. 1000 14C yrs in a cool climate and conditions that were similar to those above tree-line in Norway today. The rapid cooling at the start of the Younger Dryas stadial caused extensive disturbance, and with the development of an active cirque glacier in the catchment, plants and animals were almost exterminated from the lake by inflow of permanently cold and turbid water. Rising temperatures caused the glacier to melt at the end of the Younger Dryas. The biotic response to the rapid warming was immediate, with pioneer Ranunculus sect. Batrachium and Nitella expanding within 1-3 decades, closely followed by other elodeids. The lake witnessed a remarkable isoetid succession, with phases dominated by Limosella aquatica, Subularia aquatica, Elatine hydropiper, Isoetes echinospora, and, later, I. lacustris. About 800 yrs into the Holocene most of the macrophytes declined. The short-lived isoetids became extinct, but other taxa probably survived vegetatively. The reasons for this decline are unknown, but are probably related to nutrient depletion in combination with other factors. About 550 yrs later, I. lacustris and Nymphaea colonised, and a stable flora and vegetation developed. This study illustrates the large and rapid changes that occurred over the first 1400 yrs of the Holocene in the macrophyte flora and vegetation in Krakenes Lake before stability was attained, pointing to the value of a palaeoecological study in tracing aquatic successions over time, and highlighting our lack of knowledge of the underlying ecological factors responsible for such rapid and marked changes.

Seed banks of grazed and ungrazed Baltic seashore meadows

Abstract. The seed banks of three grazed and three ungrazed seashore meadows were studied on the west coast of Finland. 8486 seedlings (mean 13 669 seedlings/m2) germinated from cold‐treated samples (n = 343; depth = 10 cm). Most seedlings and species were monocots and perennials. The seed bank flora included 54 dicots vs. 28 monocots and 66 perennials vs. 16 annuals. The most abundant species were Juncus gerardii, Schoenoplectus tabernaemontani, Eleocharis uniglumis, Agrostis stolonifera, Juncus bufonius and Carex nigra, which made up 73% of the seed bank.Numbers of species and seedlings differed between elevation classes. Species richness was highest in elevation class 50–70 cm. The highest seed density occurred in class 20–50 cm. A model for size and species composition of the seed bank in relation to elevation is presented. The seed bank was larger and richer in species in the ungrazed than in the grazed sites, but not so in the upper elevations and closest to the open sea. Grazing reduced the size of the seed bank of Agrostis stolonifera, A. capillaris, Calamagrostis stricta, Elymus repens, Juncus bufonius, Limosella aquatica and Schoenoplectus tabernaemontani, but increased that of J. gerardii. 32 species germinated only from ungrazed samples and 11 species only from grazed ones. Multivariate classification resulted in nine sample groups. The ordination scatter was best explained by the flooding stress variables, elevation, the distance from the water line and the number of helophyte species in samples.75 species were found both in the seed bank and in the vegetation, but there was a significant lack of resemblance (in the Mantel test) due to over‐representation of some species. Eight species occurring only in the seed bank were mainly annuals or biennials (63%); those occurring only in the established vegetation (86 species) were mainly perennials (86%).

The Reproduction and Germination of Limosella aquatica

The Reproduction and Germination of Limosella aquatica