| [characterization of areas at parasitic risk for sheep reared under conditions of uncontrolled breeding on the ranges of the causses. 1. study methodology and its application to gastrointestinal strongyles]. | a flock of 50 lacaune ewes grazed three paddocks (approximately 17ha each) in rotation. thirteen areas were defined in each of the two selected paddocks on the account of vegetation and spatial utilization by the ewes. these areas represented one tenth of the total area of the paddock. for each area the following measures were estimated: species of grasses, bushes, grass disponibility, amount of faeces deposited, infective larval population of strongyles, duration of the utilization by the ewes ... | 1983 | 6660820 |
| a microsatellite marker for studying the ecology and diversity of fungal endophytes (epichloë spp.) in grasses. | randomly amplified polymorphic dna fingerprinting, which is based on pcr with arbitrary 10-nucleotide primers, were used to analyze genetic diversity among isolates of the endophytic ascomycete epichloë typhina, which were collected at a single field site from a population of one of its hosts, the grass bromus erectus. one of the polymorphic randomly amplified polymorphic dna pcr products occurred in all isolates as single bands with different but closely related sizes. two of the size variants ... | 1995 | 8526508 |
| pcr assay based on a microsatellite-containing locus for detection and quantification of epichloë endophytes in grass tissue. | a pcr assay which allows detection and quantification of epichloë endophytes in tissues of the grass bromus erectus is described. pcr with specific primers flanking a microsatellite-containing locus (ms primers) amplified fragments 300 to 400 bp in length from as little as 1.0 pg of fungal genomic dna in 100 ng of dna from infected plant material. when annealing temperatures were optimized, all epichloë and acremonium strains tested, representing many of the known taxonomic groups, yielded an am ... | 1997 | 9097449 |
| distribution of fungal endophyte genotypes in doubly infected host grasses. | fungal endophytes of the genus epichloë live intercellulary in above ground plant parts of many pooid 'grasses of the temperate regions. the associations are characterized by single genotype entities since a given host individual normally contains a single endophyte genotype. they can persist over the life span of the hosts. this study examines whether two fungal genotypes can co-exist within a host plant, and how fungal genotypes are distributed within a host in the case of double infections. w ... | 1999 | 10406120 |
| interaction between the endophytic fungus epichloe bromicola and the grass bromus erectus: effects of endophyte infection, fungal concentration and environment on grass growth and flowering | epichloe bromicola is an endophytic fungal species that systemically and perennially colonizes intercellular spaces of leaf blades, leaf sheaths and culms of bromus grass species. e. bromicola causes choke disease in b. erectus, suppressing maturation of most, if not all, host inflorescences. in an investigation of the interaction between fungus and host, we used a quantitative polymerase chain reaction technique to estimate the amount of fungal dna, and thereby fungal concentration, in host pla ... | 1999 | 10620227 |
| preparation of starch and other carbon fractions from higher plant leaves for stable carbon isotope analysis. | the measurement of the carbon isotope composition of starch and cellulose still relies on chemical isolation of these water-insoluble plant constituents and subsequent elemental analysis by isotope ratio mass spectrometry (ea/irms) of the purified fractions, while delta(13)c values of low-molecular-weight organic compounds are now routinely measured by gas chromatography/combustion/isotope ratio mass spectrometry (gc/c/irms). here we report a simple and reliable method for processing milligram q ... | 2001 | 11445894 |
| dynamic and steady-state responses of inorganic nitrogen pools and nh(3) exchange in leaves of lolium perenne and bromus erectus to changes in root nitrogen supply. | short- and long-term responses of inorganic n pools and plant-atmosphere nh(3) exchange to changes in external n supply were investigated in 11-week-old plants of two grass species, lolium perenne and bromus erectus, characteristic of n-rich and n-poor grassland ecosystems, respectively. a switch of root n source from no(-)(3)to nh(4)(+) caused within 3 h a 3- to 6-fold increase in leaf apoplastic nh(4)(+) concentration and a simultaneous decrease in apoplastic ph of about 0.4 ph units in both s ... | 2002 | 11842177 |
| mixed inoculation alters infection success of strains of the endophyte epichloë bromicola on its grass host bromus erectus. | within-host competition in multiply infected hosts is considered an important component of host-parasite interactions, but experimental studies on the dynamics of multiple infections are still rare. we measured the infection frequencies of four strains of the fungal endophyte epichloë bromicola on two genotypes of its host plant bromus erectus after single- and double-strain inoculation. double-strain inoculations resulted in fewer double, but more single, infections than expected on the basis o ... | 2002 | 11886628 |
| molecular evidence for host-adapted races of the fungal endophyte epichloë bromicola after presumed host shifts. | host shifts of plant-feeding insects and parasites promote adaptational changes that may result in the formation of host races, an assumed intermediate stage in sympatric speciation. here, we report on genetically differentiated and host-adapted races of the fungal endophyte epichloë bromicola, which presumably emerged after a shift from the grass bromus erectus to other bromus hosts. fungi of the genus epichloë (ascomycota) and related anamorphs of neotyphodium are widespread endophytes of cool ... | 2003 | 12643566 |
| do co-occurring plant species adapt to one another? the response of bromus erectus to the presence of different thymus vulgaris chemotypes. | local modification of the soil environment by individual plants may affect the performance and composition of associated plant species. the aromatic plant thymus vulgaris has the potential to modify the soil through leaching of water-soluble compounds from leaves and litter decomposition. in southern france, six different thyme chemotypes can be distinguished based on the dominant monoterpene in the essential oil, which is either phenolic or non-phenolic in structure. we examine how soils from w ... | 2004 | 15309611 |
| the cultivation bias: different communities of arbuscular mycorrhizal fungi detected in roots from the field, from bait plants transplanted to the field, and from a greenhouse trap experiment. | the community composition of arbuscular mycorrhizal fungi (amf) was investigated in roots of four different plant species (inula salicina, medicago sativa, origanum vulgare, and bromus erectus) sampled in (1) a plant species-rich calcareous grassland, (2) a bait plant bioassay conducted directly in that grassland, and (3) a greenhouse trap experiment using soil and a transplanted whole plant from that grassland as inoculum. roots were analyzed by amf-specific nested polymerase chain reaction, re ... | 2007 | 17879101 |
| genomic organization of ribosomal rna genes in bromus (poaceae). | restriction site maps of the rdna genes of nine bromus species are described. the rdna repeat units ranged from 8.2 to 11.1 kbp in length. intraspecific length variation was observed in the bamhi digestions in three of the nine species. restriction site variation was observed mainly in the intergenic spacer (igs) but was also detected in the coding region. a unique kpni site was present in the igs of bromus tectorum and bromus sericeus (subgenus stenobromus); in addition, b. sericeus contained a ... | 1996 | 18469887 |
| a leachate a day keeps the seedlings away: mowing and the inhibitory effects of festuca paniculata in subalpine grasslands. | is the release of allelochemicals by the dominant tussock grass festuca paniculata responsible for its dominance by inhibiting growth of neighbour grasses in subalpine grasslands? as such a community is also structured by mowing practices, what could be the impact of mowing on allelopathy? | 2009 | 19324898 |
| plant root carbohydrates affect growth behaviour of endophytic microfungi. | abstract peucedanum alsaticum and peucedanum cervaria represent characteristic umbellifers (apiaceae) of calcareous grasslands in central and eastern europe. both accumulate glucose, fructose, mannitol and sucrose as dominant carbohydrates in their roots. the objective of the study was to determine if endophytes utilise host plant carbohydrates differently than rhizosphere and bulk soil microfungi. inula ensifolia (asteraceae), lathyrus latifolius (fabaceae) and bromus erectus (poaceae), all pla ... | 2002 | 19709250 |
| a field study of the effects of elevated co(2) on plant biomass and community structure in a calcareous grassland. | the effects of elevated co(2) on plant biomass and community structure have been studied for four seasons in a calcareous grassland in northwest switzerland. this highly diverse, semi-natural plant community is dominated by the perennial grass bromus erectus and is mown twice a year to maintain species composition. plots of 1.3 m(2) were exposed to ambient or elevated co(2) concentrations (n = 8) using a novel co(2) exposure technique, screen-aided co(2) control (sacc) starting in march 1994. in ... | 1999 | 20135159 |