Peatlands are carbon sinks and occupy approximately 13% of Canada’s terrestrial surface of which 0.02% have been harvested for horticultural peat. The extraction of peat from natural peatlands alters the hydrology which affects the growth and survival of Sphagnum the primary peat forming vegetation. Ericaceous shrubs do not require specific water content and soil water pressure conditions for their existence and in cutover peatlands they occupy more than 70% of the surface. Rainfall interception, transpiration and root water uptake and redistribution are processes that alter water availability at the soil surface. The high abundance of shrubs at cutover peatlands will influence the surface water balance and more importantly soil water availability and, inevitably determine the success of Sphagnum reestablishment at the site. This study seeks to understand the role that ericaceous shrubs play in the surface hydrological balance at a cutover site and how these changes impact Sphagnum development. Rainfall interception, transpiration, litter layer evaporation and soil water flux was investigated in the field and lab. Approximately 334 mm of rainfall was measured over the season. The shrub canopy and litter had a maximum storage capacity of 4 and 1.2 mm respectively and intercepted ca. 36.7% (120 mm) of rainfall over the season. The effects of rainfall intensity and duration were more important than gross rainfall in determining the amount of water intercepted by the canopy, while the thickness and mass of the litter layer largely determined the storage capacity. Evapotranspiration from shrubs averaged 2.5 mm day-1 with a total of 211 mm over the season. Transpiration was 68% (142 mm) of total evapotranspiration losses, and represented the greatest water loss from the shrub canopy. From these analyses only 22% (72 mm) of rainfall is available for other soil processes and moss development. The evaporation under a litter cover is lower than bare peat and in the field represents water storage of 17 mm over the season. Reduced water input by litter interception is offset by the increased water storage under the litter. Laboratory analyses of soil water flux under ericaceous shrubs show that water loss under the shrubs was greater than bare peat. Water use under the shrubs was highest between -10 and -30 cm and was ca. 2 times greater than bare peat at the same levels. Volumetric water content (θ) decreased throughout the day and water use by shrubs during the day was twice that at night. The shrubs also maintained θ and soil water pressure (ψ) above the threshold values of 50% and -100 cm, respectively, needed for Sphagnum survival. Based on these analyses the shrubs will be beneficial to Sphagnum reestablishment and survival once the primary water losses have been compensated. I recommend raising the water table above -20 cm. In peatland restoration activities, at this level, water used between -10 and -30 cm can quickly be recharged and surface moisture maintained above threshold by capillary rise helping to offset water loss by interception and transpiration through capillary rise.

Thesis (M.S.)--Wake Forest University. Dept. of Biology, 2003. / Vita. Includes bibliographical references (leaves 20-22).

Abstract Plant reproductive success is affected by a number of factors, such as climatic conditions and plant resource status during flowering and fruiting, and pollen origin in fertilization. In the present thesis project, different aspects of plant reproductive ecology were investigated in order to identify constraints on sexual reproduction and seed set in two clonal dwarf shrubs (Vaccinium myrtillus and V. vitis-idaea) and one long-lived perennial herb (Campanula rotundifolia). The work comprised phenological observations and experiments with the clonal shrubs at natural boreal forest sites in the Oulanka National Park in northern Finland. The impact of mycorrhiza on C. rotundifolia fitness traits was tested in hand pollinations in a greenhouse experiment. Pollen origin had some effect on fruit set, and had strong effects on the number of matured seeds in all three species. Seed yield reductions upon hand self-pollination as compared with hand cross-pollination were attributed to inbreeding depression in V. myrtillus, and presumably to partial self-incompatibility in C. rotundifolia. V. myrtillus and V. vitis-idaea showed a population structure where the number of matured seeds per fruit increased with increasing distance between pollen donor and pollen recipient. Clonal growth in concert with the foraging behaviour of bumblebee pollinators is thought to cause the possibility of either uniparental or biparental inbreeding, with a strong effect on the number of matured seeds per berry. In a flower-removal experiment lasting three years, costs of fruiting to future fecundity and vegetative traits were observed, but not to future survival in V. vitis-idaea and V. myrtillus. The response was more pronounced in the evergreen than in the deciduous species. In Campanula rotundifolia, mycorrhiza was associated with a cost to the plants' reproductive effort, as plant biomass and the number of flowers produced per plant were decreased in mycorrhizal plants in comparison with non-mycorrhizal plants. There was no difference in seed number, seed weight or germination between the seeds of mycorrhizal and non-mycorrhizal plants. However, the offspring of mycorrhizal plants had a higher relative growth rate, while also having a higher seed phosphorus concentration. In summary, sexual reproduction was variably constrained by previous reproduction in Vaccinium, and contrary to expectations, by mycorrhiza in Campanula. However, mycorrhiza had positive effects on some measures of offspring fitness. In all three species, self-pollination limited seed production.

South Africa has the highest species diversity of ericaceous plants belonging to the Erica genus. There are over 850 identified species in the Cape Floral Region. The Albany Centre of Endemism (ACOE) is located within this region and is a hotspot of diversity consisting of various plant genera. The success of Erica plants is ubiquitously attributed to mycorrhizal relationships they engage in with a diverse group of fungi. This symbiosis is known as the ericoid mycorrhizal (ERM) association. The overall aim of this study was to establish the diversity of root fungi associated with Erica plants using morphological, molecular and 454 pyrosequencing techniques. Six Erica species were identified using leaf and flower morphology according to taxonomic keys. The identified plants were Erica cerinthoides, Erica demissa, Erica chamissonis, Erica glumiflora, Erica caffra and Erica nemorosa. Roots from sampled plants were stained and examined microscopically to determine their mycorrhizal status. Ericoid mycorrhizal associations together with dark septate endophyte (DSE) structures and hyphae that did not form any specific structure were observed in all the roots. In addition arbuscular mycorrhizal (AM) structures in the form of vesicles were detected in E. glumiflora and E. cerinthoides. In order to identify the culturable fungi associated with the respective hosts, sterilised roots were placed on various culture media for cultivation. Thereafter isolated fungi were morphologically classified into 67 morphotypes. These were mostly sterile and darkly pigmented. Non-sporulating mycelia of variable colouration such as white, cream-yellowish, beige, green and brown were also observed. Further identification was carried out using molecular techniques. DNA was extracted separately from pure cultures and amplified using ITS1 and ITS4 primers in a polymerase chain reaction (PCR). Thereafter sequencing and Basic Local Alignment Search Tool (BLAST) were used to identify the isolates to generic level. The fungi were taxonomically classified into 54 operational taxonomic units and 94 percent were Ascomycetes and Helotiales was the dominant order. Unclassified Helotiales with affinities to fungi currently identified as Epacrid root fungus was common in all hosts. Other isolates that were identified included Oidiodendron, Meliniomyces, Phialocephala, Cadophora, Lachnum, Leohumicola Cryptosporiopsis, Chaetomium, Acremonium and Epicoccum species. Basidiomycetes were represented by two OTUs belonging to the genus Mycena. Four OTUs comprised fungi that had no significant alignments in the reference databases. Direct root DNA extraction together with 454 pyrosequencing was used to detect the diversity of culturable and unculturable fungi associated with the identified hosts. The ITS2 region was targeted for sequencing. Although Ascomycetes remained the dominant phyla, Basidiomycetes were also detected in all host plants. Glomeromycota was present in E. caffra and E. cerinthoides. Helotiales was dominant in all Erica plants with the exception of E. cerinthoides and E. chamissonis which were dominated by the order Chaetothyriales. The OTUs identified to genus level included Epacris pulchella root fungus, Oidiodendron cf. maius, Acremonium implicatum, Leohumicola, Lachnum, Capronia and Mycena species. Culture-based techniques and pyrosequencing detected similar fungal composition comprising Ascomycetes, while, pyrosequencing was able to detect Glomeromycetes and Basidiomycetes.

No description available.

There are generally two contrasting alternatives to what limits recruitment in plants, namely the availability of seeds (seed limitation) or the quality or quantity of suitable sites (microsite limitation). Dust seeds, the smallest existing seeds, lack or have minimal nutrient reserves. During germination and initial development they consequently parasitize on mycorrhizal fungi. This is called mycoheterotrophy, and can vary in degree of fungal dependency in adult plants from full, partial or initial mycoheterotrophy. The aim of this thesis was to investigate the recruitment ecology of mycoheterotrophic Ericaceae (tribe Pyroleae) species with dust seeds, and to determine what limits their recruitment. The investigated species were: Chimaphila umbellata, Moneses uniflora, Orthilia secunda, Pyrola chlorantha, P. minor and P. rotundifolia. This aim was achieved by combining field experiments (seed sowing) with isotope analysis and fungal host pyrosequencing. Results provide evidence that the species in Pyroleae are heterogeneous, not only with regard to their degree of mycoheterotrophy, but also concerning germination and early seedling development. A combination of microsite and seed limitation is thus likely to be of importance for all studied species, but the relative importance of these limitations varies among species. Despite having adaptations for wind dispersal the majority of the seeds were deposited in close vicinity of the seed source. But with high seed production at least some seeds should be able to disperse long-distance. Seedlings of all studied species were found to associate with a wide range of ectomycorrhizal fungi, at least during their initial developmental stages. There seems to be a tendency for host narrowing in some Pyroleae species, but not as strict as the host specialization seen in fully mycoheterotrophic Monotropa hypopitys, supporting the hypothesis of geographical and developmental host shifts. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: In press. Paper 4: Manuscript.</p>

Der Ursprung, die Entwicklung und die Formierung von Laubblatt-Mustern konnten bei ausgewählten variegaten Formen der Araceae, Asteraceae, Ericaceae, Maranthaceae und Rosaceae erklärt werden. Die Pflanzen wurden je nach Problematik untersucht und in drei verschiedene Gruppen verteilt: In der ersten Gruppe, Blattmuster mit unregelmäßiger makulater Musterung, Monstera deliciosa, Syngonium podophyllum und die Sorten 'Pirol' und 'Luyona' von Dendranthema grandiflorum zeigen ein unregelmäßiges Laubblattmuster und keine weiß-randigen bzw. weißkernigen Periklinalchimären. Mischzellen wurden durch direkte (mikroskopisch) und indirekte (In-vitro-Kultur und Selbstungen) Nach der Plastidenentmischung in den Schichten des Sprossmeristems wurde bei Syngonium, Monstera und den zwei Sorten von Dendranthema die GW-Form als einzige stabile Periklinalchimäre nachgewiesen. In der zweiten Gruppe, Immerspaltende Periklinalchimären, die chimärische Konstitution GA bei Spiraea bumalda 'Goldflame' konnte durch Wurzelaustriebe (BATESON-Test) und die Adventivsprossinduktion aus Kallus nachgewiesen werden. Darüber hinaus konnten mehrfach perikline Aufspaltungen der ersten Sprossscheitelschicht (Reduplikation von L1) nachgewiesen werden, die zur Entstehung der Panaschierung von 'Goldflame' zur Entmischung führten. Bei den Untersuchungen der In-vitro-Regenerate aus der Kalluskultur und der Wurzelaustriebe an S. bumalda 'Shirobana' wurde festgestellt, dass diese Pflanze keine Chimäre ist und das auftretende Muster der Blüten genetisch kontrolliert ist. In der dritten Gruppe, Hypoderm und Beeinflussung der Musterbildung: Die unmaskierten Binnenfelder bei Ctenanthe lubbersiana 'Variegata' und der Rhododendron-Hybride 'Goldflimmer' sind durch die Existenz eines Hypoderms zu erklären. Bei Ctenanthe lubbersiana 'Variegata' befindet sich ein Hypoderm an der Blattoberseite und der Blattunterseite. Bei 'Goldflimmer' liegt nur unter der oberen Epidermis ein einschichtiges Hypoderm vor. Infolgedessen fehlt an der Blattoberseite die Maskierung Das gelbe Binnenfeld des Blattmusters ist durch eine grüne Mesophyllschicht unterlagert. / The origin, development and formation of foliage-leaf-patterns could be explained with selected variegaten forms of the Araceae, Asteraceae, Ericaceae, Marantaceae and Rosaceae. In order to prove this the plants were examined according to the problem and classified in three different groups: In the first group, leaf-patterns with irregular maculated patterns, Monstera deliciosa, Syngonium podophyllum and the sorts 'Pirol' and 'Luyona' of Dendranthema grandiflorum showed an irregular foliage-leaf-pattern, thought neither to show periclinal chimeras with white edges nor with green edges. Mixed cells were detected by direct (microscopic) and indirect (In vitro culture and self pollination) test. After the plastid sorting out in the layers of the meristems, the green over white Form was proven with Syngonium, Monstera and the two sorts of Dendranthema as a single stable periclinal chimera. In the second group, eversporting periclinal chimeras, the green over aurea chimeral constitution with Spiraea bumalda 'Goldflame' was proved by the regeneration of adventitious shoots from their roots (BATESON-Test) and also by the induction of adventitious bud from callus. Periclinal divisions of the first layer of meristems (reduplication of L1), which are responsible for the appearing of green pattern of the leafs was proved many times. Examination of the regenerated shoots from callus and from the adventitious shoots from roots of S. bumalda 'Shirobana' showed that this plant is not a chimera and that the appearing pattern of the blooms is genetically controlled. In the third group, hypoderm and influence of the pattern-formation, the unmasked inner-fields with Ctenanthe lubbersiana 'Variegata' and the Rhododendron-hybrid 'Goldflimmer' were explained through the existence of one layered hypoderm under the upper Epidermis as well as over the lower Epidermis of C. lubbersiana 'Variegata', thought in 'Goldflimmer' it is only found a one layer Hypoderm under the upper epidermis. Subsequently, the masking is missing at the upper-leaf side the yellow inner-field of the leaf-pattern is through a green Mesophyllslayer masked.

A study was undertaken of plants used for treatment of diabetic symptoms by traditional healers of the Eeyou Istchee Cree (Canada), Lukomir Highlanders (Bosnia & Herzegovina), and Q’eqchi’ Maya (Belize). All antidiabetic plants were ranked by syndromic importance value (SIV) based on 15 symptoms, all of which were recognized by the Cree and Maya and 8 by the Highlanders. The Cree used only 18 species, the Highlanders 41, and the Maya 150, numbers which reflect the diversity of flora in their region. Vaccinium (Ericaceae) was one of the few genera in all three regions and the only consensus genus between the Cree and Highlander study sites. The Q’eqchi’ Maya ethnobotany did not present any cross-cultural consensus genera with Cree or Highlander medicinal plants, perhaps due to major biogeographic differences. In ethnopharmacological studies, Vaccinium species and Q’eqchi’ antidiabetic plants were tested in an assay relevant to diabetes, the advanced glycation endproduct (AGE) inhibition assay. Boreal and tropical Vaccinium species were potent inhibitors of AGEs and demonstrated concentration dependent inhibition, with a half maximal inhibitory concentration (IC50) range of 5.93–100 µg/mL. Phenolic content ranged from 80.3 to 201 µg/mL in boreal samples and from 1470 to 2170 µg/mL in tropical samples. Tropical species have a greater phenolic content and AGE inhibition. Seven Q’eqchi’ antidiabetic plant species were tested and all plant extracts showed AGE-inhibition. The IC50s ranged from 40.8 to 733 µg/mL, and the most active was Tynanthus guatemalensis Donn.. Tynanthus guatemalensis IC50 was about fives times greater (less active) than the mean ± SE IC50 reported for six tropical Vaccinium species of Vaccinium (8.77 ± 0.79 μg/mL). The highest consensus and most active Maya antidiabetic plant, Tynanthus guatemalensis Donn. Sm. was discovered to be an important plant recorded in archeological artifacts from the Late Classic Maya period (~750 CE). Ancient Maya used a cross shaped sign (k’an glyph) as a decorative element on Late Classic polychrome vessels and murals. The sign was believed to be the xylem template for a plant used as a flavouring in cacao drinks. However, the plant was incorrectly identified in the literature as Pimenta dioica (L.) Merr. (common name: Allspice) based on a common name and aromatic plant quality – not from a botanical voucher specimen. Pimenta dioica wood does not have a cross shape visible in the xylem but a unique character visible after a cross section of T. guatemalensis, is the xylem's cross shape organization. Wood of T. guatemalensis' also has an "allspice" aroma. Tynanthus guatemalensis is most likely the true botanical template behind the ancient Maya k’an glyph and this finding would show the continuity of use of this medicinal plant from ancient to modern times. Vaccinium was selected for an in depth phytochemical analysis using modern metabolomic methods. Nuclear magnetic resonance (1H NMR) was used to evaluate leaf extract spectra to provide information on (1) the taxonomic identity and (2) quantities of bioactive metabolites across multiple sites. Spectra clearly differentiated leaf samples of V. angustifolium, V. boreale, V. corymbosum, V. macrocarpon, V. myrtilloides, V. myrtillus, V. ovalifolium, and V. uliginosum according to generic, subgeneric, specific, phenotypic circumscriptions. Quantification of chlorogenic acid and hyperoside were replicated with a method that is highly reproducible across multiple sites with different NMR equipment. This methodology provides an important new approach to taxonomy and quality control for plants and natural health products.

A study was undertaken of plants used for treatment of diabetic symptoms by traditional healers of the Eeyou Istchee Cree (Canada), Lukomir Highlanders (Bosnia & Herzegovina), and Q’eqchi’ Maya (Belize). All antidiabetic plants were ranked by syndromic importance value (SIV) based on 15 symptoms, all of which were recognized by the Cree and Maya and 8 by the Highlanders. The Cree used only 18 species, the Highlanders 41, and the Maya 150, numbers which reflect the diversity of flora in their region. Vaccinium (Ericaceae) was one of the few genera in all three regions and the only consensus genus between the Cree and Highlander study sites. The Q’eqchi’ Maya ethnobotany did not present any cross-cultural consensus genera with Cree or Highlander medicinal plants, perhaps due to major biogeographic differences. In ethnopharmacological studies, Vaccinium species and Q’eqchi’ antidiabetic plants were tested in an assay relevant to diabetes, the advanced glycation endproduct (AGE) inhibition assay. Boreal and tropical Vaccinium species were potent inhibitors of AGEs and demonstrated concentration dependent inhibition, with a half maximal inhibitory concentration (IC50) range of 5.93–100 µg/mL. Phenolic content ranged from 80.3 to 201 µg/mL in boreal samples and from 1470 to 2170 µg/mL in tropical samples. Tropical species have a greater phenolic content and AGE inhibition. Seven Q’eqchi’ antidiabetic plant species were tested and all plant extracts showed AGE-inhibition. The IC50s ranged from 40.8 to 733 µg/mL, and the most active was Tynanthus guatemalensis Donn.. Tynanthus guatemalensis IC50 was about fives times greater (less active) than the mean ± SE IC50 reported for six tropical Vaccinium species of Vaccinium (8.77 ± 0.79 μg/mL). The highest consensus and most active Maya antidiabetic plant, Tynanthus guatemalensis Donn. Sm. was discovered to be an important plant recorded in archeological artifacts from the Late Classic Maya period (~750 CE). Ancient Maya used a cross shaped sign (k’an glyph) as a decorative element on Late Classic polychrome vessels and murals. The sign was believed to be the xylem template for a plant used as a flavouring in cacao drinks. However, the plant was incorrectly identified in the literature as Pimenta dioica (L.) Merr. (common name: Allspice) based on a common name and aromatic plant quality – not from a botanical voucher specimen. Pimenta dioica wood does not have a cross shape visible in the xylem but a unique character visible after a cross section of T. guatemalensis, is the xylem's cross shape organization. Wood of T. guatemalensis' also has an "allspice" aroma. Tynanthus guatemalensis is most likely the true botanical template behind the ancient Maya k’an glyph and this finding would show the continuity of use of this medicinal plant from ancient to modern times. Vaccinium was selected for an in depth phytochemical analysis using modern metabolomic methods. Nuclear magnetic resonance (1H NMR) was used to evaluate leaf extract spectra to provide information on (1) the taxonomic identity and (2) quantities of bioactive metabolites across multiple sites. Spectra clearly differentiated leaf samples of V. angustifolium, V. boreale, V. corymbosum, V. macrocarpon, V. myrtilloides, V. myrtillus, V. ovalifolium, and V. uliginosum according to generic, subgeneric, specific, phenotypic circumscriptions. Quantification of chlorogenic acid and hyperoside were replicated with a method that is highly reproducible across multiple sites with different NMR equipment. This methodology provides an important new approach to taxonomy and quality control for plants and natural health products.