|Wednesday, July 07|
Comparison of bryophyte cultivation in three different types of substrates
Wanlop NualKam, Division of Conservation Biology, School of Interdisciplinary Studies, Mahidol University, Kanchanaburi Campus, 199 Moo 9 Saiyok District, Kanchanabur
* Weerachon Sawangproh, Division of Conservation Biology, School of Interdisciplinary Studies, Mahidol University, Kanchanaburi Campus, 199 Moo 9 Saiyok District, Kanchanabur, Thailand
Bryophytes are recognized to be difficult for cultivation and maintenance in glasshouse condition. This preliminary study aims to assess suitable growing substrates, cultivation method, and means for evaluating growth. Three acrocarpous mosses (i.e., Hyophila involuta, Barbula consanguinea, and H. apiculata) commonly thrive on laterite soil (iron-rich soil) in the vicinity of Kanchanaburi Campus of Mahidol University were chosen to compare the growth without extra nutrient supply during two months. Three types of substrates were native soil where mosses were collected, commercial sand, and commercial peat moss. The growth was measured every second week using three indices i.e. growth area, the number of new plants, and wet weight. Our results showed that the most suitable substrates for three mosses ranked by three indices were sand, native soil, and peat moss, respectively. Mosses can be successfully grown on sand and laterite soil if kept out of the direct light source and moist. Determining the number of new plants developed from propagules is the most reliable natural marker for growth in our mosses. Visual assessments of plant health showed that even spraying regularly with water did not prevent scorching and desiccation. The adverse impact of scorching and desiccation on plant growth is worst in peat moss. This study suggests that peat moss is not a suitable substrate for cultivating terricolous mosses because of its low pH condition. It would be feasible to use sand as media for growing, propagating, and maintaining mosses as experimental material in the future.
Intra- and interspecific interaction during early stages of moss development in vitro
Jingmin Cheng, Environmental Microbial Ecology, Tsinghua University
* Isidora Loncarevic, Lund University (Sweden), ArcticMass (Iceland), Sweden
Nils Cronberg, Lund University (Sweden)
Interspecific interaction between six common bryophyte species (Atrichum undulatum, Byrum argenteum, Ceratodon purpureus, Funaria hygrometrica, Hypnum cupressiforme and Leptobryum pyriforme) was assessed in in vitro conditions, where spores of these six species were sowed on agar plates and their germination and growth compared and evaluated. Besides investigating whether spore germination and protonemal growth are affected by interspecific interaction, another aim was to check if there was a priority effect dependent on the first colonizer and if spore germination and gametophyte formation is density-dependent in the single-species. Treatments were: (1) single species cultures (controls); (2) pairwise species cultures inoculated simultaneously) and (3) with a time lag of 20 days between the first and the second species. Strong pairwise interactive effects when sowing spores of different species simultaneously or with the delay of 20 days were noticed, suggesting the presence of interspecific competition and priority effects.
Predictors of epiphytic bryophyte and lichen biomass and hydrologic impact across a boreal-temperate ecotone
* Daniel Stanton, University of Minnesota, United States
Tana Route, University of Minnesota
Abigail Meyer, University of Minnesota
Abby Glauser, University of Colorado, Boulder
Robert Smith, USDA Forest Service
Epiphytic bryophytes and lichens can be an important component of forest ecosystems. Although some estimates of the biomass and potential impacts of bryophytes and lichens exist, these have (quite understandably) often focused on ecosystems with visibly large epiphyte loads. While important, these estimate may not be representative of many other forest types. We surveyed epiphyte communities at 82 sites across Minnesota (USA). This state covers the intersection of 4 North American biomes (Eastern Temperate Forest, Boreal Forest, Prairie and Aspen Parkland), providing a multi-regional perspective despite the limited geographic scope. We combine field estimates of trunk, canopy (inferred from twig litter) and ground cover with measurements of specific mass and water-holding capacity to calculate forest level epiphyte biomass and water-holding capacity (WHC). Site (e.g. forest type, dominant phorophyte, physiography, etc) and community characteristics (species richness) were used to identify the best predictors of epiphyte properties. We found very high variation in epiphyte. reaching ~1 ton/ha but often far less. Potential WHC was mostly much lower than reported in wetter forests (mostly 0.1-0.2 mm/ha) but occasionally quite significant. Forest type was a more important predictor than geographic location alone, reflecting the importance of phorophyte identity in determining epiphyte community properties. Lichens and bryophyte showed contrasting responses to latitude and climate. Identifying predictors of epiphyte biomass across forest types and biomes is important to modeling impacts of future changes in climate.
The importance of moss shoot and colony traits on their desiccation dynamics
Lucía Moreno Spiegelberg, Universidad Autónoma de Madrid, Spain
Ángel Lareo Fernández, Universidad Autónoma de Madrid
* Nagore García Medina, Universidad Autónoma de Madrid
Mosses lack the ability to actively regulate their water content. Consequently, they depend on an intermittent water supply that conditions their metabolic activity. Moisture-keeping strategies are crucial for plant survival specially in the Mediterranean where plants are subject to long drought periods. However, we know little about the influence of shoot and colony traits on desiccation dynamics. In our study we subjected the colonies of two Mediterranean mosses (Syntrichia princeps and Pleurochaete squarrosa ) to a 60% density reduction in 4 gradual steps. In each step we measured desiccation rates, colony morphology (weight, height, density, number of shoot, shoot overlap), and shoot traits (length and number of leaves). Our results show an acceleration of the desiccation rate related to density reduction that varies with the species and the morphological traits. These results highlight the importance of these traits, and especially colony density for the maintenance of moisture.
Are hornworts delicate plants? Contrasting effects of desiccation on gametophytes and sporophytes of hornworts
* Gabriel Felipe Peñaloza Bojacá, Laboratório de Sistemática Vegetal, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Brazil
Tiago Vilas-Boas, Laboratório de Fisiologia Vegetal, Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais
Juan Carlos Villarreal , Département de Biologie, Université Laval
Adaises Simone Maciel da Silva, Laboratório de Sistemática Vegetal, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais
Desiccation tolerance (DT) is the ability of an organism or structure to completely dry and subsequently survive from that air-dry state. DT may have played an important role during early land colonization by plants. Hornworts are excellent models along bryophyte lineages to examine desiccation effects as they have contrasting life histories (i.e., niches: epiphytes (e.g Dendroceros) and non-epiphytes; spores: green and non-green) that may be associated with DT. Here we show the main effects of DT on gametophytes and spores of four genera of hornworts (Dendroceros, Nothoceros, Phaeoceros and Anthoceros), exposed to different relative humidity, duration dry, and rate of rehydration treatments. All DT treatments affected chlorophyll fluorescence (Fv/Fm) of the gametophytes, with species-specific responses: Dendroceros crispatus and D. crispus performed better than Phaeoceros carolinianus and Nothoceros vincentianus, including the fast recovery of Fv/Fm values after rehydration. Spore survival and sporeling size differed among the species examined (in general, with the highest survival in P. carolinianus and lowest in D. crispatus), with no effect of duration dry on survival. Our data evidenced that the gametophytes of epiphytic species (D. crispatus and D. crispus) were more efficient at withstanding drying effects under different conditions. Conversely, the capacity of non-green spores of P. carolinianus, Anthoceros lamellatus, and green spores of D. crispus to support DT. Desiccation tolerance responses, gametophyte and spore longevities highlight important trade-offs of spore dispersal and fast colonization (e.g., Dendroceros), and the spore banks of Phaeoceros and Anthoceros species.
The phenology of Bryophytes revisited after 150 years through eDNA
* Fia Bengtsson, Lund University, Sweden
Nils Cronberg, Lund University
Johan Ekroos, Lund University
Jose Villegas, Umeå University
Abu Siddique, Umeå University
Per Stenberg, Umeå University
Bryophyte spores are generally dispersed by wind, forming a spore cloud that differ in composition throughout the year due to the spore dispersal phenology of individual species. Spores have few traits that allow identification when air-borne, therefore sporulation phenology has thus far been carried out by observation of sporophyte maturation in situ – a topic largely untouched since the work of Arnell in the late 1800s. In this project, we investigate the phenology of sporulation using eDNA (environmental DNA) originating from air filters collected by the FOI (Swedish Defence Research Agency) to monitor radioactive fallout. Filters were collected weekly since the 1960s at a weather station in Kiruna, northern Sweden. The project Swedish Biodiversity In Time and Space (SweBITS) sequenced a subset of these filters, seasonally restricted to periods with air temperature above 0°C, creating a large data base covering samples between 1974–2009. Reads match various kinds of organisms, including a high proportion of bryophyte spores. Here we present preliminary data for a few chosen genera, for which we ask: 1) What are their main sporulation periods, and can we identify peaks of spore spread? 2) Can we see any changes in sporulation phenology during the time span? 3) Can we detect shifts in sporulation phenology between our modern dataset and the reports by Arnell in the 1800s? 4) Can we identify possible environmental and climatic causes for phenological shifts? We discuss methodological problems and their solutions, potentials and limitations of this kind of unusual datasets.
Biome evolution in subfamily Cercidoideae (Fabaceae)
* Charlotte Hagelstam-Renshaw, Université de Montréal, Canada
Warren Cardinal-McTeague, Agriculture and Agri-Food Canada Ottawa Research and Development Centre
Anne Bruneau, Université de Montréal
Studies show that some plant lineages have a tendency to remain within the same biome over time (biome conservatism), whereas others appear to have the ability to adapt more easily to new biomes (biome shifts). Subfamily Cercidoideae includes 13 genera and approximately 335 species that are found in many biomes around the world, particularly in the tropical regions of South America, Asia and Africa. The main objective of this project is to study biome shifts in a phylogenetic context, determining the extent to which there have been biome shifts or biome conservatism throughout the evolution of Cercidoideae lineages. After establishing an updated and community-verified species list including all known synonyms and their accepted names, occurrence records were downloaded from the Global Biodiversity Information Facility (GBIF) and other herbarium databases. These records were then subject to an extensive data cleaning process in order to match the occurrences to their accepted names as well as to remove doubtful occurrences such as non-vouchered records, cultivated records and country centroids. Species distribution maps were produced in order to attribute individual species to biomes. Based on previously generated phylogenies, we will be evaluating the number of biome shifts across the phylogeny. Preliminary analyses suggest multiple shifts, in particular between pairs of adjacent biomes such as the savanna and rainforest biomes, as well as the succulent and rainforest biomes. Ultimately, this approach will help better understand the evolutionary dynamics of plant species distribution through space and time.