| analysis of fusarium causing dermal toxicosis in marram grass planters. | in the european coastal dunes, marram grass (ammophila arenaria) is planted in order to control sand erosion. in the years 1986 to 1991, workers on the wadden islands in the netherlands planting marram grass showed lesions of skin and mucous membranes, suggesting a toxic reaction. fusarium culmorum dominated the mycoflora of those marram grass culms that were used for planting. this plant material had been cut and stored for more than one week in the open. the fusarium toxin deoxynivalenol (don) ... | 1996 | 9063007 |
| use of ammophila arenaria for dune stabilization in south africa and its current distribution-perceptions and problems. | / this paper examines the use of the european dune pioneer plant ammophila arenaria (marram or european beach grass) for dune stabilization in south africa in the past and present, its present distribution in south africa, and the perceptions of coastal management agencies and the public about its further use. the planting of a. arenaria became the most important means of dune stabilization, by human intervention, along the south african cape coast in this century. its modern distribution from t ... | 1999 | 10501860 |
| endophytic nitrogen fixation in dune grasses (ammophila arenaria and elymus mollis) from oregon. | several tropical grasses harbor symbiotic nitrogen-fixing bacteria within their stem and rhizome tissue that may contribute to the nitrogen nutrition of the host plant. we present evidence here that sand dune grasses (ammophila arenaria and elymus mollis) from oregon also contain nitrogen-fixing bacteria. surface-sterilized stem and rhizome tissue from these species possess acetylene reduction (nitrogen fixation) activity and large populations (10(5) to 10(6) cfu/g fresh weight) of bacteria. the ... | 2004 | 19712295 |
| rapid identification of cyst (heterodera spp., globodera spp.) and root-knot (meloidogyne spp.) nematodes on the basis of its2 sequence variation detected by pcr-single-strand conformational polymorphism (pcr-sscp) in cultures and field samples. | cyst and root-knot nematodes show high levels of gross morphological similarity. this presents difficulties for the study of their ecology in natural ecosystems. in this study, cyst and root-knot nematode species, as well as some ectoparasitic nematode species, were identified using the second internal transcribed spacer (its2) sequence variation detected by polymerase chain reaction-single-strand conformational polymorphism (pcr-sscp). the its2 region was sufficiently variable within the taxa i ... | 2000 | 10972762 |
| invasive grasses, climate change, and exposure to storm-wave overtopping in coastal dune ecosystems. | the world's coastal habitats are critical to human well-being, but are also highly sensitive to human habitat alterations and climate change. in particular, global climate is increasing sea levels and potentially altering storm intensities, which may result in increased risk of flooding in coastal areas. in the pacific northwest (usa), coastal dunes that protect the coast from flooding are largely the product of a grass introduced from europe over a century ago (ammophila arenaria). an introduce ... | 2012 | 23504839 |
| coastal foredune evolution: the relative influence of vegetation and sand supply in the us pacific northwest. | biophysical feedbacks between vegetation and sediment are important for forming and modifying landscape features and their ecosystem services. these feedbacks are especially important where landscape features differ in their provision of ecosystem services. for example, the shape of coastal foredunes, a product of both physical and biological forces, determines their ability to protect communities from rising seas and changing patterns of storminess. here we assessed how sand supply and changes ... | 2015 | 25833242 |
| detection and characterization of fungal infections of ammophila arenaria (marram grass) roots by denaturing gradient gel electrophoresis of specifically amplified 18s rdna. | marram grass (ammophila arenaria l.), a sand-stabilizing plant species in coastal dune areas, is affected by a specific pathosystem thought to include both plant-pathogenic fungi and nematodes. to study the fungal component of this pathosystem, we developed a method for the cultivation-independent detection and characterization of fungi infecting plant roots based on denaturing gradient gel electrophoresis (dgge) of specifically amplified dna fragments coding for 18s rrna (rdna). a nested pcr st ... | 1997 | 9327549 |
| behaviour and transport of radionuclides in soil and vegetation of a sand dune ecosystem. | a sand dune ecosystem in the vicinity of the british nuclear fuels reprocessing plant at sellafield, cumbria, uk was used to examine the spatial, temporal and depth distributions of 134cs, 137cs, 238pu, 239 + 240pu and 241am in soil and in two species of vegetation (festuca rubra, ammophila arenaria). core samples showed evidence of the accumulation of radionuclides derived mainly from sea-to-land transfer. accumulated deposits of radioactivity (0-0.1 m) lie within the range: 1.1-3.4 bq kg-1 (13 ... | 2001 | 11381556 |
| community analysis of arbuscular mycorrhizal fungi associated with ammophila arenaria in dutch coastal sand dunes. | a polymerase chain reaction-denaturing gradient gel electrophoresis (pcr-dgge) approach for the detection and characterization of arbuscular mycorrhizal fungi (amf) 18s ribosomal dna (rdna) was developed and applied to the study of amf communities associated with the main sand-stabilizing plant species of the dutch sand dunes, marram grass (ammophila arenaria, l.). dna was extracted directly from plant roots, soil or isolated amf spores, and prominent bands resulting from amf-specific dgge profi ... | 2002 | 11928709 |
| release from native root herbivores and biotic resistance by soil pathogens in a new habitat both affect the alien ammophila arenaria in south africa. | many native communities contain exotic plants that pose a major threat to indigenous vegetation and ecosystem functioning. therefore the enemy release hypothesis (erh) and biotic resistance hypothesis (brh) were examined in relation to the invasiveness of the introduced dune grass ammophila arenaria in south africa. to compare plant-soil feedback from the native habitat in europe and the new habitat in south africa, plants were grown in their own soil from both europe and south africa, as well a ... | 2004 | 15309610 |
| changes in vegetation and soil characteristics in coastal sand dunes along a gradient of atmospheric nitrogen deposition. | a field survey was conducted to detect signals of atmospheric nitrogen (n) in 11 dune systems along a nitrogen deposition gradient in the united kingdom. in the mobile and semi-fixed dunes, above-ground biomass was positively related to n inputs. this increase was largely due to increased height and cover of ammophila arenaria. in the long term, this increased biomass may lead to increased organic matter accumulation and consequently accelerated soil development. in the fixed dunes, above ground ... | 2004 | 15375731 |
| diversity of amf associated with ammophila arenaria ssp. arundinacea in portuguese sand dunes. | dune vegetation is essential for the formation and preservation of sand dunes and the protection of the coast line. coastal sand dunes are harsh environments where arbuscular mycorrhizal fungi (amf) play an important role in promoting plant establishment and growth. we present a study of the diversity of amf associated with a. arenaria ssp. arundinacea in two locations of the portuguese coast under a mediterranean climate. these two locations were selected to compare a well-preserved dune system ... | 2006 | 17043895 |
| soil microorganisms control plant ectoparasitic nematodes in natural coastal foredunes. | belowground herbivores can exert important controls on the composition of natural plant communities. until now, relatively few studies have investigated which factors may control the abundance of belowground herbivores. in dutch coastal foredunes, the root-feeding nematode tylenchorhynchus ventralis is capable of reducing the performance of the dominant grass ammophila arenaria (marram grass). however, field surveys show that populations of this nematode usually are controlled to nondamaging den ... | 2007 | 17345102 |
| glomus perpusillum, a new arbuscular mycorrhizal fungus. | a new arbuscular mycorrhizal fungal species of genus glomus, g. perpusillum (glomeromycota), forming small, hyaline spores is described and illustrated. spores of g. perpusillum were formed in hypogeous aggregates and occasionally inside roots. they are globose to subglobose, (10-)24(-30) microm diam, rarely egg-shaped, oblong to irregular, 18-25 x 25-63 microm. the single spore wall of g. perpusillum consists of two permanent layers: a finely laminate, semiflexible to rigid outer layer and a fl ... | 2009 | 19397199 |
| genetic variation within a dominant shrub species determines plant species colonization in a coastal dune ecosystem. | the diversity and structure of plant communities is often determined by the presence and identity of competitively dominant species. recent studies suggest that intraspecific variation within dominants may also have important community-level consequences. in a coastal dunes ecosystem of northern california, we use a decade-old common garden experiment to test the effects of a genetically based architectural dimorphism within a dominant native shrub, baccharis pilularis, on plant colonization suc ... | 2010 | 20462137 |
| apparent competition with an invasive plant hastens the extinction of an endangered lupine. | invasive plants may compete with native plants by increasing the pressure of native consumers, a mechanism known as "apparent competition." apparent competition can be as strong as or stronger than direct competition, but the role of apparent competition has rarely been examined in biological invasions. we used four years of demographic data and seed-removal experiments to determine if introduced grasses caused elevated levels of seed consumption on native plant species in a coastal dune system ... | 2010 | 20836448 |
| biophysical feedback mediates effects of invasive grasses on coastal dune shape. | vegetation at the aquatic-terrestrial interface can alter landscape features through its growth and interactions with sediment and fluids. even similar species may impart different effects due to variation in their interactions and feedbacks with the environment. consequently, replacement of one engineering species by another can cause significant change in the physical environment. here we investigate the species-specific ecological mechanisms influencing the geomorphology of u.s. pacific north ... | 2012 | 22834384 |
| invasive congeners differ in successional impacts across space and time. | invasive species can alter the succession of ecological communities because they are often adapted to the disturbed conditions that initiate succession. the extent to which this occurs may depend on how widely they are distributed across environmental gradients and how long they persist over the course of succession. we focus on plant communities of the usa pacific northwest coastal dunes, where disturbance is characterized by changes in sediment supply, and the plant community is dominated by t ... | 2015 | 25658824 |
| effect of an invasive plant and moonlight on rodent foraging behavior in a coastal dune ecosystem. | understanding how invasive plants may alter predator avoidance behaviors is important for granivorous rodents because their foraging can trigger ripple effects in trophic webs. previous research has shown that european beach grass ammophila arenaria, an invasive species in coastal california, affects the predation of other seeds by the rodents microtus californicus, peromyscus maniculatus, and reithrodontomys megalotis. this may be due to lower perceived predation risk by rodents foraging in clo ... | 2015 | 25679785 |
| nutrient and productivity relations of the dune grasses ammophila arenaria and elymus mollis : i. blade photosynthesis and nitrogen use efficiency in the laboratory and field. | a comparative study of blade photosynthesis and nitrogen use efficiency was made on the dune grasses ammophila arenaria and elymus mollis. in the laboratory, an open system gas analysis apparatus was used to examine the gas exchange characteristics of blades as influenced by nitrogen supply. plants were grown under near-ambient coastal conditions in a greenhouse near bodega bay, california, and given either high or low supplies of nitrogen in an otherwise complete nutrient solution. in the field ... | 1983 | 28310179 |
| nutrient and productivity relations of the dune grasses ammophila arenaria and elymus mollis : ii. growth and patterns of dry matter and nitrogen allocation as influenced by nitrogen supply. | the purpose of this research was to investigate the influence of nitrogen availability on growth and the patterns of dry matter and nitrogen allocation of the dune grasses ammophila arenaria and elymus mollis. plants were grown from rhizome segments under near-ambient coastal conditions and received either high or low supplies of nitrogen. sequential harvests, and the separation of plant material into live blade, dead blade, tiller, rhizome, and root fractions were made during the exponential ph ... | 1983 | 28310180 |
| biotic soil factors affecting the growth and development of ammophila arenaria. | to study the origin of replant disease of ammophila arenaria (l.) link the growth and development in sand originating from the rhizosphere of a natural ammophila vegetation was compared with the growth in sand from the sea-floor. in a greenhouse experiment, the growth of ammophila seedlings in rhizosphere sand, when compared with that in sea sand, was significantly reduced. as sterilization by means of gamma-irradiation increased the biomass production of ammophila seedlings significantly, it wa ... | 1988 | 28312214 |
| relative importance of biotic and abiotic soil components to plant growth and insect herbivore population dynamics. | plants are affected by several aspects of the soil, which have the potential to exert cascading effects on the performance of herbivorous insects. the effects of biotic and abiotic soil characteristics have however mostly been investigated in isolation, leaving their relative importance largely unexplored. such is the case for the dune grass ammophila, whose decline under decreasing sand accretion is argued to be caused by either biotic or abiotic soil properties. | 2010 | 20886078 |
| contrasting covariation of above- and belowground invertebrate species across plant genotypes. | 1. invertebrate species generally do not respond independently to genotypic variation in plants, giving rise to clusters of species that naturally associate with or avoid certain genotypes. this covariation causes coevolution to be diffuse rather than pairwise. studies on this topic, however, have never considered the belowground invertebrate community, leaving a critical gap in our understanding. 2. we investigated the covariation among naturally colonising above- and belowground invertebrate s ... | 2011 | 20964685 |
| interactions between nematodes and their microbial enemies in coastal sand dunes. | european foredunes are almost exclusively colonised by ammophila arenaria, and both the natural succession and the die-out of this plant have been linked to populations of plant-parasitic nematodes (ppn). the overarching aim of this study was to investigate top-down control processes of ppn in these natural ecosystems through comparative analyses of the diversity and dynamics of ppn and their microbial enemies. our specific aims were, first, to identify and quantify ppn microbial enemies in euro ... | 2012 | 22622874 |
| mechanism of control of root-feeding nematodes by mycorrhizal fungi in the dune grass ammophila arenaria. | root-feeding herbivores can affect plant performance and the composition of natural plant communities, but there is little information about the mechanisms that control root herbivores in natural systems. this study explores the interactions between the pioneer dune grass ammophila arenaria, arbuscular mycorrhizal fungi (amf) and the root-feeding nematode pratylenchus penetrans. our objectives were to determine whether amf can suppress nematode infection and reproduction and to explore the mecha ... | 2006 | 16441763 |