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Common reed (Phragmites) interacts with a large suite of other organisms including cryptogams attached to live or dead culm bases. We report an unusual observation of at least ten taxa of lichens and hepatics attached to persistent reed stubble on the swampy bank of freshwater Cypress Creek north of Tampa, Hillsborough County, Florida. This bryoid material included the minute, leafy hepatics Microlejeunea globosa, Microlejeunea cf. ulicina, Myriocoleopsis minutissima, and Frullania cf. inflata; and the lichens Arthonia subdiffusa, Chrysothrix xanthina, Opegrapha viridis, Phaeographis sp., Physcia sp., and an unidentified species of Parmeliaceae. These generally corticolous or epiphyllous taxa have not previously been reported from common reed, and suggest unrecognized complexity in both cryptogamic microhabitats and reed epiphytes.

The genus Frullania (Frullaniaceae, Porellales, Jungermanniopsida) comprises 21 species in Southeastern North America. Screening about 850 independent collections of common species of Frullania taken from the hark of trees in Alabama, Georgia, Mississippi, North Carolina, Tennessee, and Virginia revealed a surprisingly high number of parasitic fruit-body forming ascomycetes. Particularly well represented are the Hypocreales (Sordariomycetes), of which 14 species (out of 17 occurring on Frullania worldwide) in five genera on eight host species are documented here based on 235 specimens. The genera Bryotria, Laniatria, and Periantria are proposed as new as well as the following ten species: Bryocentria biannulata, B. chlysothrix, B. lusor, B. navicula. B. pentarnera. Bryonectria anisopoda, Bryotria adelpha, B. urophora, Laniatria myxostoma, and Periantria bellacaptiva. Three new combinations are proposed. Calonectria frullaniae is transferred to Periantria. Nectria foertheri (on Porella sp.) and N. lagodes to Bryotria. Bryocentria brongniartii, Bryonectria callicarpa. Bryotria lagodes, and Periantria frullaniae are new records for North America. The latter species which destroys developing sporophytes within the perianths was found to be by far the most frequent. The hypocrealean fungi on Frullania in Southeastern North America are much more diverse than those of Central Europe. Biotrophic and necrotrophic species occur in both regions. The main distinguishing characters are size and colour of perithecium, structure of the perithecial wall, and size, shape and septation of the ascospores. Perithecia sometimes occur in high densities (up to eight per square mm) and, in spite of their small size, are relatively conspicuous due to their vivid colouration. Nevertheless, beyond the present study, knowledge of the Frullania inhabiting ascomycetes in North America is almost non-existent.

Two bryophilous species of the order Hypocreales (Ascomycetes) are introduced as new. Bryonectria aphanes (Bionectriaceae) has hyaline ascomata, four-spored asci, three-celled ascospores and numerous phialids and appressoria on the hyphae. It is recorded on the moss Platygyrium repens (Pylaisiadelphaceae, Hypnales) from Maine, U.S.A. Trichosphaerella goniospora (Niessliaceae) forms dark ascomata beset with setae deeply rooted in the peridial wall and eight two-celled ascospores. They disarticulate very early during sporogenesis resulting in 16 irregularly cubic part-spores. The species was collected on the liverwort Ptilidium pulcherrimum (Ptilidiaceae, Jungermanniales) in New Brunswick, Canada. The Niessliaceae belong to a hitherto unknown line within bryophilous fungi. On the other hand, bryophytes extend the spectrum of substrates for black hypocrealean fungi.

Photosynthetic microorganisms play crucial roles in aquatic ecosystems and are the major primary producers in global marine ecosystems. The discovery of new bacteria and microalgae that play key roles in CO(2) fixation is hampered by the lack of methods to identify hitherto-unculturable microorganisms. To overcome this problem we studied single microbial cells using stable-isotope probing (SIP) together with resonance Raman (RR) microspectroscopy of carotenoids, the light-absorbing pigments present in most photosynthetic microorganisms. We show that fixation of (13)CO(2) into carotenoids produces a red shift in single-cell RR (SCRR) spectra and that this SCRR-SIP technique is sufficiently sensitive to detect as little as 10% of (13)C incorporation. Mass spectrometry (MS) analysis of labelled cellular proteins verifies that the red shift in carotenoid SCRR spectra acts as a reporter of the (13)C content of single cells. Millisecond Raman imaging of cells in mixed cultures and natural seawater samples was used to identify cells actively fixing CO(2), demonstrating that the SCRR-SIP is a noninvasive method for the rapid and quantitative detection of CO(2) fixation at the single cell level in a microbial community. The SCRR-SIP technique may provide a direct method for screening environmental samples, and could help to reveal the ecophysiology of hitherto-unculturable microorganisms, linking microbial species to their ecological function in the natural environment.

Epiphyllous bryophytes are poorly documented for temperate eastern North America. Ten liverwort taxa and one moss species are reported as epiphylls on Rhododendron maximum from the Appalachian Plateau (Fentress County, Tennessee, and Menifee County, Kentucky). The Kentucky localities represent the northernmost documented sites for bryophyte epiphylls in eastern North America. Three North American liverwort endemics, Lejeunea ruthii, Leucolejeunea clypeata, and Radula obconica, and the moss, Platygyrium repens, are newly reported as epiphylls. Colony size ranged from

Bryoplana xerophila, a new genus and species of limnoterrestrial protoplanelline platyhelminth, was found in moss and soil covering a concrete wall in northern Alabama, USA. Bryoplana xerophila is the first taxon of limnoterrestrial Protoplanellinae recorded from North America and is one of the few rhabdocoels known from dry habitats. It is unique within Protoplanellinae in lacking rhabdites, having a pharynx rosulatus in the frontal half of the body, and lacking sclerotized parts in the male system. Notes on encystment, reproduction and feeding behavior are given. An updated identification key to all known genera of Protoplanellinae is presented.

Plagiochila (sect. Arrectae) punctata, previously known from the Neotropics, Africa and Europe, has been collected on a sandstone cliff in a rockhouse type environment in Tennessee, new to North America. Maximum likelihood analyses based on nrITS1–5.8S-ITS2 sequences of several species of Plagiochila sect. Arrectae resolve the Tennessee specimen in a robust P. punctata subclade with accessions from Ecuador and the Democratic Republic of the Congo.

The typically lithophilic Polypodium appalachianum was discovered as a canopy epiphyte 35 to 40 m above ground on a horizontal branch of a champion-size Liriodendron tulipifera in the Great Smoky Mountains National Park. Occurring along with this first documentation of P. appalachianum from the tree canopy was an assemblage of normally terrestrial mosses, an unusual assortment of collembola (springtails), and a flightless proturan insect species previously known only from soil and litter. The distinctive features of this canopy habitat may duplicate some ecological conditions usually found only at ground level, establishing the opportunity for translocating an entire community and providing biologists with new insights on the origin of some epiphytes.

An osmotic priming treatment of 14 days in a −1.0 MPa polyethylene glycol solution improves the germination performance of a highvigour seed lot of leek (Allium porrum L., cv. Verina). Using in vivo pulse-labelling, two-dimensional polyacrylamide gel electrophoresis and fluorography, five polypeptides were found to be synthesized in embryonic tissue at 14 days of priming that were not present at 4 days of germination without prior priming. These polypeptides were still synthesized at 6 h of germination following priming. This time point lies in the 6–12 h lag phase in protein synthesis previously observed in leek embryo tissue during germination of primed seeds where there is little increase in the rate of synthesis over that seen at the end of priming. None of the polypeptides was synthesized at 2 days of germination after priming, a period of seedling growth. The five polypeptides appear to be specifically associated with the priming period. Two additional polypeptides were found in leek embryos that were synthesized at higher levels at the end of priming than during germination alone. These continued to be synthesized, at lower levels in leek embryo tissue upon germination after priming. Several polypeptides were identified in leek endosperm tissue which were synthesized at higher levels during priming than during germination and also two polypeptides whose synthesis appeared to be specific to germination.

Loss of vigour in leek (Allium porrumL.) seed lots is accompanied by the appearance of damage to ribosomal RNA in quiescent embryo tissue. Polyethylene glycol osmopriming treatments of such low-vigour seed permit replacement of this damaged ribosomal rRNA over a 7-day priming period. Low-vigour leek seeds germinated for 6 days without a prior osmopriming treatment still exhibit evidence of damaged ribosomal RNA in embryo tissue. Osmoprimed leek seeds dried back whilst still in the desiccation-tolerant state retain most of the benefits conferred by priming treatments. Osmoprimed leek seeds dried back when having reached the desiccation-sensitive state germinate poorly, if at all, and exhibit much reduced rates of protein synthesis in embryo tissue upon rehydration compared to desiccation-tolerant seeds. Embryo tissue from dried back, desiccation-tolerant seeds exhibits the capacity for much higher levels of protein synthesis than embryo tissue from unprimed seeds at equivalent stages of imbibition. RNA levels continue to increase in embryo tissue upon rehydration of dried back, desiccation-tolerant leek seeds but not in desiccation-sensitive seeds. Loss of protein synthetic capacity in desiccation-sensitive seeds during rehydration is accompanied by increasing levels of ribosomal RNA degradation. Such ribosomal RNA degradation may be indicative of the germinative capacity of leek seeds dried back after osmopriming treatments.

The cosmopolitan family Porellaceae includes about 60 species in two or three genera: the large genus Porella and the monospecific Ascidiota and Macvicaria (alternatively Porella subg. Macvicaria). Maximum parsimony, maximum likelihood and Bayesian inference of phylogeny of a dataset including three markers (rbcL, trnL–trnF region of cp DNA, nrITS region) of 96 accessions resulted in similar topologies supporting the generic status of Ascidiota. Macvicaria is nested in a subclade of Porella. Relationships among species of Porella are in general well resolved and many terminal nodes achieve good statistical support whereas basal relationships are at best moderately supported. Multiple accessions of single species are usually placed in monophyletic lineages. Accessions of P. platyphylla split into a European and a North American clade with one accession from North America embedded within the European samples. The Macaronesian endemic P. inaequalis is closely related to the Asian species P. grandiloba. Porella obtusata and P. canariensis cannot be separated on the basis of the sequence data presented in this study. The molecular topologies indicate a range extension of the Asian P. gracillima subsp. urogea to Eastern North America and of the Neotropical P. swartziana to South Africa. Current supraspecific classifications of Porella are not reflected in the molecular topologies with a correlation between genetic variation and the geographical distribution of the related accessions rather than a correlation between genetic variation and morphology.