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Results tagged “written by katherine”

Jun 20, 2012: Chondrostereum purpureum

Chondrostereum purpureum

An entry written by former 2011-2012 work-study student Katherine that I had squirreled away today. She writes:

Today, we have a lovely purple fungus known as Chondrostereum purpureum or silverleaf fungus. Many thanks to Marianne (aka marcella2/tovje@Flickr) for this wonderful image of Chondrostereum purpureum covered in exuding water droplets (via the UBC Botany Photo of the Day Flickr Pool). Please see a previous Botany Photo of the Day entry on Fomitopsis pinicola for more on guttating fungi.

Some of you may be familiar with Chondrostereum purpureum, or at least the disease it causes in trees (silverleaf), as this fungus can be parasitic on a number of ornamental and/or orchard woody species, particularly those in Prunus (cherries & plums and more), Malus (apples) and Pyrus pears. A clear explanation of silverleaf disease is provided by New Zealand's Horticulture and Food Research Institute.

Another common name for Chondrostereum purpureum is violet crust, as individuals starts their growth as a crust on exposed sapwood, then develop to be about 3cm in width with a "tough rubbery texture", according to the Wikipedia entry. Subsequently, the crust "dries out, becomes brittle, and turns a drab brown or beige" with the "infected wood [...] stained a darker tint".

In addition to rosaceous woody plants, Chondrostereum purpureum can also infect many other broad-leaved species (and even a few conifers), giving the species an extensive global distribution (mirroring to a large extent its host plants).

Chondrostereum purpureum is not considered edible. However, it does have an effective economic use in inhibiting resprout and regrowth of cut tree stumps. This application of the fungus can particularly be used by the electrical industry for stumps near power lines. The species is also undergoing testing as a possible control for competing vegetation in conifer plantations by the British Columbia Ministry of Forests and Range (though given how easily fungi spread, one wonders if this could have deleterious effects on the British Columbia orchard industries, even with assurances that this "mycoherbicide is restricted to the target vegetation").

For those interested, MycoBank.org provides microscopic and spore descriptions for their available cultures of Chondrostereum purpureum.

May 15, 2012: Hylocereus costaricensis

Hylocereus costaricensis

With today's entry, we conclude Katherine Van Dijk's contributions as a work-study student for Botany Photo of the Day (though the official end date was actually two weeks ago). Thank you Katherine! For this entry, she writes:

To finish our series on white-flowered plants with medicinal properties, we have another wonderful contribution from 3Point141@Flickr. This photograph features Hylocereus costaricensis, commonly known as Costa Rica pitahaya, Costa Rica pitaya or Costa Rica night-blooming cactus. 3Point141@Flickr also has a 12 image set which captures the blooming of this magnificent species: Hylocereus costaricensis.

Pacific Island Ecosystems at Risk (PIER) describes Hylocereus costaricensis as a vigorous vine (up to 10cm in stem width), with white and yellow flowers sometimes exceeding 30cm in length. The site notes Hylocereus costaricensis as native to Costa Rica (costaricensis = "of Costa Rica"), Nicaragua and Panama, but unfortunately invasive in Hawaii.

Hylocereus and a few closely-related genera of cacti are well-known for their tasty dragon fruit or pitaya. The fruit of Hylocereus costaricensis is where medicinal uses are found. In Le Bellec, F. et al., 2006. Pitahaya (Hylocereus spp.): a new fruit crop, a market with a future (PDF). Fruits. 61:237-250, the authors note that dragonfruit is a significant source of antioxidants, including betalains. These compounds are currently being studied for medical efficacy, with some indications that they can be useful in preventing certain diseases (e.g., some forms of cancer). A different medicinal use for Hylocereus costaricensis was examined in a study which had results suggesting that an ethanol extract of the fruit pulp was successful in increasing sperm viability and production rate in mice (and could therefore presumably be used as a male fertility agent). See: Aziz, F. and M. Noor. 2010. Ethanol extract of dragon fruit and its effects on sperm quality and histology of the testes in mice. Biomedical Research. 21(2):126-130.

May 14, 2012: Vanilla roscheri and Vanilla planifolia

Continuing the series of white-flowered medicinal plants, Katherine writes:

Today's image is of Vanilla roscheri, and was taken by Ton Rulkens (tonrulkens@Flickr) "in the wild on the north Mozambique coast (Mecufi District)". The illustration of Vanilla planifolia is from Köhler's Medizinal-Pflanzen.

Vanilla roscheri is a rare orchid found in eastern and southeastern Africa. Due to deficient data, the conservation status of the species globally is unknown, but in South Africa it is considered endangered due to urban expansion, habitat degradation, invasive species and agriculture. Commonly known as Roscher's vanilla, Vanilla roscheri is found in open bushlands, scrub, mangroves and open evergreen scrub to an elevation of about 1050m (3450 ft.). Sweetly fragrant, the flowers of the plants bloom in the (tropical and subtropical) winter. Plants are succulent vining climbers.

Medicinal information for "vanilla" almost always refers to the extract of vanillin from the commercial Vanilla planifolia, originally of Mesoamerica and northern South America. Vanilla roscheri also seems to contain the compound, as use of the species has been documented in traditional medicines of African indigenous peoples. An excellent article on the origin and use of vanilla is available from UCLA's Louise M. Darling Biomedical Library's Medicinal Spices Exhibit, where the following from Robert Bentley and Henry Trimen's Medicinal Plants; being descriptions with original figures of the principal plants employed in medicine and an account of the characters, properties, and uses of their parts and products of medicinal value (London, Churchill, 1880) is quoted: "Vanilla is an aromatic stimulant, with a tendency towards the nervous system. It has also been regarded as an aphrodisiac. It has been employed as a remedy in hysteria, low fevers, impotency, etc. But its use as a medicine is obsolete in this country, although still sometimes employed on the Continent and elsewhere."

May 10, 2012: Peumus boldus

Peumus boldus

Another in the series on white-flowered medicinal plants written by Katherine, today's entry has an illustration from Köhler's Medizinal-Pflanzen (in the public domain, via Wikimedia Commons). Katherine writes:

Peumus boldus was described and published by Molina in 1782. Synonyms include Ruizia fragrans and Boldoa fragrans. Among its many common names are boldo, boldu, boldina, and baldina. This Chilean endemic species is the only representative of the genus.

Mature plants of this dioecious (individual plants are either male or female) evergreen tree attain about 6-8m (15-25 ft) in height. Shown in the illustration with pink-tinged white flowers, photographs of living material range from white to a pale yellow colour. The Plants for a Future database entry on Peumus boldus notes: "The small fruits are dried and used as beads in necklaces. When warmed by the body or the sun they release the scent of cinnamon". The leaves are the primary part of the plant used, however.

Wikipedia touches on some of the uses of the leaves: "In Chile, Uruguay, and Paraguay boldo is frequently mixed with yerba mate or other teas to moderate its flavor. In Brazil and Paraguay, many families keep a boldo plant at home for this purpose, although boldo teabags are readily available in nearly all supermarkets. It is believed in Southeastern Brazil that the leaves of the boldo plant can be used as an effective hangover and upset stomach cure." A longer list of traditional medicinal uses is available from Plants for a Future (linked above), including: treatment of gallstones, liver pain, gonorrhoea, urinary tract infections, intestinal parasites and rheumatism.

The European Medicines Agency, in its Evaluation of Medicines for Human Use, noted in its final assessment report on Peumus boldus (PDF): "[Assessor's Overall Conclusions] Sufficient data are available to develop a Community herbal monograph on the traditional use of Peumus boldus Molina, folium provided the indications are suitable for self-medication. The proposed indications are in accordance with the Commission E monograph (Blumenthal, 2000): Traditional herbal medicinal product for symptomatic relief of dyspepsia and mild spasmodic disorders of the gastrointestinal tract."

but cautioned:

"Duration of use should be limited to 2 weeks. Use of boldo leaf is not recommended in children and adolescents and should be avoided during pregnancy and lactation. Boldo leaf is contra-indicated where there is obstruction of the bile duct, cholangitis liver disease, gallstones or any other biliary disorder that would require medical supervision. The use of comminuted herbal substance as such and of ethanolic extracts of boldo leaf are not considered acceptable for traditional herbal medicinal products in view of the potential risks associated with the toxic ascaridole (see Health Issues) constituent".

May 9, 2012: Pseudobombax ellipticum

Pseudobombax ellipticum

Katherine continues with the series she's assembled:

Today's image for the series on medicinal white-flowered plants is Pseudobombax ellipticum (shaving-brush tree), thanks to 3Point141@Flickr. The image was taken at Palma Sola Botanical Park, Bradenton, Florida, USA.

According to the USDA GRIN site, Pseudobombax ellipticum is native to Mexico, Cuba and Guatemala. GRIN lists two synonyms, Bombax ellipticum and Carolinea fastuosa, as well as some common names: shaving-brush tree in English, pochote or pochotl in Spanish, and rakborstträd in Swedish. Jim Conrad's Naturalist Newsletter also provides additional names for Pseudobombax ellipticum: amapolo (Mayan), xiloxóchitl (cornsilk flower, Aztecan and current in some parts of Mexico), and cabellos de ángel, or angel hair (Spanish).

A species description written by Navarrette-Tindall and Núñez for the Tropical Tree Seed Manual is available via rngr.net (Reforestation, Nurseries and Genetic Resources: Pseudobombax ellipticum. Among the other details about this white- or pink-flowering species, the account notes the species is winter- to spring-flowering, typically after losing its leaves. The authors also provide several uses of Pseudobombax ellipticum: the wood is used as firewood or for carving dishes; the trees for ornamental purposes and as living fences; the toasted seeds as food; and the fine fruit fibres to fill pillows and mattresses or to insulate refrigerators. Medicinally, the authors cite González (1994) and Guzmán (1980): "In El Salvador, the tea of the flowers is used for gastrointestinal ailments and the tea of the fresh bark is used to treat diabetes". The link above to Jim Conrad's newsletter also describes some medicinal uses by local peoples.

Researchers have determined that Pseudobombax ellipticum was one of several important plant species depicted in Mayan ceramics (e.g., pots used as burial urns or incense holders). See Sacred plants of the Maya forest for a popular account from the BBC, or investigate Zidar, C. and W. Elisens. 2009. Sacred Giants: Depiction of Bombacoideae on Maya Ceramics in Mexico, Guatemala, and Belize. Economic Botany. 63(2):119-129. doi: 10.1007/s12231-009-9079-2.

May 8, 2012: Plumeria obtusa 'Singapore'

Plumeria obtusa 'Singapore'

Today, we'll start Katherine's series of entries on white-flowered medicinal plants. She writes:

This image of Plumeria obtusa 'Singapore' is courtesy of Dinesh Valke (dinesh_valke@Flickr). For this series on medicinal plants, one should assume that traditional and sometimes scientifically unproven uses are noted, unless otherwise stated. I made my best attempts to find scientific articles where possible.

In Mabberley's Plant-Book, 8 species are noted for Plumeria, with two receiving mention as often-cultivated ornamentals in this tropical American genus: Plumeria obtusa (native to the West Indies) and Plumeria rubra (native from Mexico to Panama). Both of these species are widely cultivated throughout the tropics. Despite having only a couple handfuls of species, hundreds of cultivated varieties have been selected or hybridized, including today's evergreen cultivar. If researching Plumeria rubra, do note that many sites and references use the synonym Plumeria acuminata.

The U.S. National Tropical Botanical Garden (NTBG) provides wonderful descriptions of both Plumeria obtusa and Plumeria rubra, along with their uses. The site notes that Plumeria flowers are used to make lei in Hawai'i, due in part to providing large numbers of showy flowers that retain colour and fragrance. The same source also notes that the scent varies widely among cultivars; this reference by Richard Criley of the Department of Tropical Plant and Soil Sciences at the University of Hawaiʻi at Mānoa details 40 or so cultivars, with comments on fragrance: Plumeria in Hawaiʻi (PDF). The National Tropical Botanical Garden also makes note of the use of Plumeria as an ornamental for cemeteries (hence one of the common names, graveyard flower) and temples (known as temple flower in India and Sri Lanka). Today's cultivar is commonly known as 'Singapore' graveyard flower.

Medicinally, Plumeria species have traditionally been used to treat itches, swellings and fevers, skin eruptions and abscesses, dysentery, herpes, syphilis, coughs and as a purgative. A recent test of the leaves of Plumeria obtusa for anticancer properties did not find significant positive results (unlike some other members of the Apocynaceae): Wong et al. 2011. Antiproliferative and phytochemical analyses of leaf extracts of ten Apocynaceae species. Pharmacognosy Research. 3(2):100-106. However, a 2006 study by Gupta et al. suggested that an extract from the leaves of Plumeria acuminata can soothe inflammation in "both acute and chronic models": Antiinflammatory evaluation of leaves of Plumeria acuminata. BMC Complememnt Altern Med. 6(36).

Apr 4, 2012: Hibiscus waimeae subsp. hannerae

Hibiscus waimeae subsp. hannerae

Katherine again writes today's entry:

Today, we have a beautiful image of Hibiscus waimeae subsp. hannerae thanks to Anna Kadlec via the Botany Photo of the Day Submissions Forum.

Hibiscus waimeae has two subspecies (sometimes designated varieties): Hibiscus waimeae subsp. hannerae and Hibiscus waimeae subsp. waimeae. Today's featured subspecies is generally smaller overall (including smaller flowers) when compared to the subspecies waimeae, though it has larger leaves. Hibiscus waimeae subsp. hannerae is endemic to Hawaii, and known by the Hawaiian names: Aloalo, Koki'o kea, and Koki'o ke'oke'o, In English, the taxon is commonly known as Kauai white hibiscus, minature Hawaiian white hibiscus, small Kauai white hibiscus, and white Kauai rosemallow. Native Plants Hawaii (see previous link) notes that the genus name stems from "hibiscos, Greek for 'mallow', and the epithet waimeae refers to the Waimea Canyon, Kaua'i where this species is found." That reference also states that Hibiscus waimeae subsp. hannerae blooms year round, although sporadically (often ceasing during winter or early spring), and is unusual among hibiscus in that it is one of only two species (both native to Hawaii) to have fragrant flowers.

According to the U.S. National Tropical Botanical Garden (NTBG) page for Hibiscus waimeae subsp. hannerae, these single flowers last only one day and are "white when open in [the] morning and fade to pink in the afternoon" with a staminal column that is pink to crimson. Easily grown in cultivation (it was previously used as decoration near huts), the taxon is considered endangered. It occurs only in Kaua'i's northwestern valleys of Hanakapi'ai, Limahuli, and Kalihi Wai at elevations of 240 - 1,200m (800 - 3,900ft) (see previous link). Its rarity is in part due to the ease with which Hibiscus waimeae subsp. hannerae hybridizes, and, according to the IUCN Red List, partly due to habitat being "frequently damaged by feral pigs and invaded by introduced plants". The IUCN Red List also notes that the population on Kalihi Wai is seemingly extirpated.

Mar 28, 2012: Antidesma bunius

Antidesma bunius

Katherine is the author of today's entry. She writes:

Today's photo is thanks to 3Point141@Flickr (original image | additional image | Botany Photo of the Day Flickr Pool).

Antidesma bunius has a multitude of common names in English and many other languages. In English, these include bignay, Chinese-laurel, currant tree, wild cherry, and salamander-tree. According to USDA GRIN (linked above re: English common names), Antidesma bunius has two synonyms: Antidesma dallachyanum and Stilago bunius. A third synonym, Antidesma dallachyi, is recorded by the Australian Tropical Rainforest Plants site.

This dioecious woody species grows to about 5 meters tall. With male and female flowers on different individual plants, it should be apparent that the plant in today's photograph is a female. In the wild, the species is present up to elevations of 900m. Antidesma bunius is a widely distributed species (see GRIN link above) of temperate and tropical Asia, Queensland, and on islands of the central Pacific, but it is also cultivated widely outside of its native range in other tropical and subtropical areas.

According to the Australian Tropical Rainforest Plants site, "the fruit of [Antidesma bunius] is used in North Queensland to make jams or syrups and was once very popular and sought after". However, it is oft considered bitter as well. Wikipedia's page for Antidesma bunius elaborates, noting that "while the majority of the indigenous population tastes bignay as sweet, people of European ancestry often find it bitter to the point of inedibility. This phenomenon is inversely linked to the taste perception of phenylthiocarbamide [...]" (see: Henkin, R and Gillis, W. 1977. Divergent taste responsiveness to fruit of the tree Antidesma bunius. Nature. 265: 536-537). In addition to the species being used for food, Antidesma bunius has some economic value for its wood, though the National Herbarium Nederland page on Antidesma mentions that the scent of the bark is "not so great".

Mar 12, 2012: Heterosigma akashiwo

Heterosigma akashiwo

We'll conclude the UBC Celebrate Research Week series a bit belatedly -- I was hoping to receive higher resolution images, but people get busy, so we'll make do. Katherine introduces today's researcher:

Richard White is a PhD student of Dr. Curtis Suttle, Professor and Associate Dean, Research (Faculty of Science) (Suttle lab). Today's entry is about an algae-infecting virus. The left image is of the HaNIV virus (from Lawrence, J et al. 2001. A novel virus (HaNIV) causes lysis of the toxic bloom-forming alga Heterosigma akashiwo (Raphidophyceae). J. Phycol. 37:216-222), and the second two images are of the alga Heterosigma akashiwo.

Richard writes about "Unraveling the viral diversity amongst marine phytoplankton":

Heterosigma akashiwo (pictured centre and right) is responsible for toxic blooms that cause mass economic impacts to marine fish population's worldwide. The name akashiwo itself comes from Japanese meaning "red tide", which is a phenomenon that this organism causes in marine ecosystems. The toxicity of blooms caused by Heterosigma akashiwo can affect all trophic levels of the marine environment from copepods, fish, echinoderms and mollusks, but the toxin is unknown.

Heterosigma akashiwo has a true adversary that regulates its population and helps safeguard Earth's ocean from its devastating bloom effects. A wide range of viruses infect Heterosigma akashiwo (pictured above left is an ssDNA virus - HaNIV), and these can be involved in the termination of blooms. Understanding these viruses provides insight into the natural control mechanisms that regulate red tides in nature.

Katherine adds: For those who are interested, you can see more about harmful algal blooms. A British Columbian resource also outlines their effect on people (Paralytic Shellfish Poisoning), as well as local beach closures.

Mar 8, 2012: Cyclobalanopsis glaucoides

Organized once again by Katherine, here's today's entry with an introduction from her:

Continuing the series for UBC's Celebrate Research Week">UBC Celebrate Research Week is another entry thanks to Dr. Roy Turkington, this time from his research undertaken in collaboration with Professor Zhou Zhe-khun. Dr. Turkington informed me that the first image is a general view of the canopy at the Ailaoshan Reserve. The second image shows one of three treatment plots of research being conducted by M.Sc student, Jessica Lu, where they are testing the effects of litter on soil nutrients, soil invertebrates, and germination & establishment of seedlings. The final image is from Jin Jin Hu (PhD student), showing his enclosures for testing the effects of rodents (and other seed predators) on germination and establishment of seedlings. Dr. Turkington writes:

Yunnan Province in southwestern China is a biodiversity hotspot containing more than 20000 species of higher plants (6% of the world's total). The biodiversity of this region is under threat from loss of habitat due to logging and the planting of economic plants. Fifteen to twenty percent of higher plant varieties are endangered, threatening the existence of 40,000 species of organisms related with them. One-third of all species of oak (approximately 150 species, Quercus plus Cyclobalanopsis) in these Asian evergreen broad-leaved forests belong to the genus Cyclobalanopsis and one of the dominant species in this genus is Cyclobalanopsis glaucoides. As a dominant species, it provides a major structural component of these diverse forests, yet seedlings of Cyclobalanopsis glaucoides are rarely observed, and even in years of higher acorn production, the number of oak seedlings is not significantly increased. Thus, an understanding of the factors that influence the long-term survival of Cyclobalanopsis glaucoides is critical to the maintenance of these forests.

These studies began in 2006 and are on-going. Specifically, we are testing if there is a relationship between large weather cells, such as the Pacific Decadal Oscillation and the Southern Oscillation Index, with acorn production, and if acorn germination & seedling establishment is affected by weevils, small mammals, birds, or the quality and quantity of litter in the understorey of these forests.

Mar 7, 2012: Effects of Nutrient Changes on Plant Communities

Katherine continues with another entry she's organized for UBC's Celebrate Research Week series. She introduces Dr. Roy Turkington:

Dr. Roy Turkington is a professor of plant ecology at UBC based under the Department of Botany and the Biodiversity Research Centre. The Turkington lab is currently undergoing research in collaboration with Dr. Lauchlan Fraser from Thompson Rivers University, BC and Professor Zhou Zhe-khun at the Xishuangbanna Tropical Botanical Garden and the Kunming Institute of Botany, Yunnan Province in China. Dr. Roy Turkington has been kind enough to share with us two entries regarding his research, first from the Kluane region in the Yukon, Canada, and in an upcoming entry, the Ailaoshan sites in Yunnan, China.

Today's entry, from Dr. Turkington, has photographs from the Yukon Kluane region, more of which are available on the Turkington lab website. The images are of Linnaea borealis (twinflower), Chamerion angustifolium (fireweed) and a study plot. Dr. Turkington writes:

It has been suggested that the application of nutrients to northern communities may simulate some of the same effects in the plant community that might be produced by global environmental change. Global changes such as increasing CO2 concentrations, increasing deposition of nitrogen and sulphur pollutants, and rising temperatures will have crucial impacts on nutrient cycles consequently leading to changes in primary production and species composition. Climate change will increase the supply of nutrients, by stimulating decomposition processes, and increase the rate of soil carbon accumulation. These changes will of course be modified by the interactions between plants and their environment. In the Kluane region we might initially expect that bryophytes, lichens, prostrate growth forms (e.g., Arctostaphylos uva-ursi/ and Linnaea borealis), and low nutrient-requiring species will be suppressed or eliminated by faster-growing, more upright clonal species such as the forbs, Chamerion angustifolium (syn. Epilobium angustifolium) and Mertensia paniculata.

As species composition changes in our plots we inevitably lose a number of species and raises the question if species-impoverished systems will perform less well or less efficiently than their counterpart systems with a full complement of species. To investigate these questions we used a removal experiment called "a functional group knock-out". This was achieved by removing plant functional groups (graminoids, leguminous forbs and non-leguminous forbs) individually and observing changes in community dynamics and ecosystem function. Response variables measured include both community dynamics (species frequency measures and leaf area index) and ecosystem function (above-ground biomass, above and below-ground decomposition rates [using litter bags], nutrient supply rates [using ion exchange membranes], light interception and soil water content). And yes, loss of species does lead to a loss of ecosystem function.

Mar 6, 2012: Mimulus spp.

Today's entry is again organized by Katherine for the UBC Celebrate Research Week series. She introduces Seema Sheth:

Seema Sheth is a Ph.D. student (Colorado State University) with the recently-appointed-to-UBC Dr. Amy Angert (Assistant Professor in the UBC Department of Botany (lab web page)). The lab studies the processes of adaptation in plants. Today's entry is from their work on species of Mimulus. The photographs, Seema informs me, are of Mimulus angustatus (purple/pink flowers) from Grass Valley, California, and Mimulus guttatus (yellow flowers) from the Red Hills Area of Critical Environmental Concern, California.

Seema (with input from Dr. Angert) writes about the evolutionary ecology of rarity in western North American Mimulus:

Most species are geographically rare, and all species occupy a limited number of areas, yet the causes of variation in the sizes and limits of species' geographic distributions are poorly understood. Identifying causes of rarity provides important insights into ecological and evolutionary processes such as dispersal, speciation, extinction, and adaptation. Understanding the factors that shape species' distributions also can improve our ability to prioritize species and areas of conservation concern, forecast changes in species' distributions in response to climate change, and predict the rate and spread of invasive species.

Properties of species' ecological niches, defined here as the set of environmental conditions under which births exceed deaths, may explain differences in geographic range size among species. For example, if a species can persist under a broader range of environmental conditions, then it should be able to occupy a greater geographic area than a species with a narrower environmental tolerance. This hypothesis predicts a positive relationship between niche breadth and range size. On the other hand, rare species may be more dispersal-limited, either because of intrinsically low dispersal ability or because they are younger and have had less time to expand across the landscape.

We are testing the niche breadth hypothesis within western North American monkeyflowers (genus: Mimulus, family: Phrymaceae), a diverse group of wildflowers that occupies a wide variety of habitats, including aquatic, alpine, grassland, and desert environments, and contains several species that specialize on microhabitats such as serpentine soils, copper mine tailings, geysers, and marble cliff walls. Due to their short generation times (6-12 weeks), ease of propagation, high seed production, and genomic resources, species in the genus Mimulus have become an emerging model in evolutionary ecology (Wu, CA et al. 2008. Mimulus is an emerging model system for the integration of ecological and genomic studies. Heredity 100:220-230). Further, the geographic distributions of Mimulus species vary markedly in size, are well-described, and largely encompassed within federally protected lands in western North America (Beardsley, PM et al. 2004. Patterns of evolution in Western North American Mimulus (Phrymaceae). American Journal Of Botany 91:474-489), thus representing an ideal group for testing hypotheses to explain variation in the size and limits of species' ranges.

To test the hypothesis that species with broader environmental niches occupy larger geographic areas than species with narrow environmental tolerances, we are using comparative and experimental studies. First, we compiled ~17,000 georeferenced occurrence records for Mimulus species that occur in western North America. We used these locality data along with climatic variables (such as annual mean temperature and precipitation seasonality) to model the climatic niche of each species and to quantify range size in multiple ways. Regardless of how range size is quantified, our results strongly support the prediction that range size increases with climatic niche breadth across species (see figure below ). To experimentally test these results, we are now quantifying niche breadth in terms of survival and growth of individuals across a range of temperature and soil moisture levels for six pairs of closely related Mimulus species that differ in range size. This will allow for a more comprehensive understanding of how broader niches may lead to larger ranges. Species with restricted distributions are thought to be more prone to chance extinctions than widely distributed species. Further, species with small ranges and/or narrow niche breadth may be more sensitive to climate change. Thus, understanding the relationship between physiology, niche characteristics, and range size will allow for better predictions of species' responses to changing climate.

Mimulus spp. - Niche Breadth Figure

Key to the figure (please note: not yet published formally and still requires peer review): Support for the hypothesis that niche breadth explains variation in geographic range size among species (N = 72). Raw species' data are shown here (transformed to meet assumption of normality), but results support predictions even after correcting for phylogenetic non-independence and sampling effort. Two closely related species that vary drastically in range size (see inset panel) and climatic niche breadth are highlighted here, and are part of an ongoing experimental study testing whether geographically restricted species have lower thermal niche breadth than their widely distributed close relatives.

Mar 5, 2012: Chlamydomonas reinhardtii

Chlamydomonas reinhardtii

Katherine has been busy assembling this year's UBC Celebrate Research Week series, starting with today's entry:

Dr. Jae-Hyeok Lee is an Assistant Professor with the UBC Department of Botany. He describes the research currently being undertaken by the Lee Lab as work in the hope of "understanding the ancestral conditions prior to the origin(s) of plant development".

Dr. Lee continues: In order to do this, the lab studies cellular mechanisms that orchestrate zygote development in Chlamydomonas, a green alga genus. Systematic approaches, including molecular genetics, comparative genomics and live cell imaging, have so far yielded a grand hypothesis that the green algal zygote is functionally and evolutionarily related to the plant sporophyte where most plant-specific structures such as leaf, seed, and flower have evolved. We believe that deeper understanding of green algal zygotes will guide us to follow individual evolutionary steps in the preceding billions of years from unicellular green algae to flowering plants.

The picture above was taken by a phase-contrast microscope and captures the most exciting and fierce moment of a green alga, Chlamydomonas reinhardtii during its sexual mating. Oval shaped, and averaging 5 micrometers in length, a Chlamydomonas cell (in the lower right corner) is a very good swimmer, utilizing two flagella on its apical side to move as it looks for either sunlight or a mating partner. Nutrient starvation induces cells to become gametes that participate in mating reaction. They are either of two sexual types, plus or minus, each reacting to its opposite sex as their flagella adhere only to the flagella of the other sex (red arrow). Upon flagellar adhesion, two gametes shed their cell walls (yellow arrow) and proceed through a cellular fusion process which takes only a couple of minutes (blue arrow). The union of cells initiates dramatic restructuring to differentiate as a dormant zygote that can endures a cold and dry winter.

Feb 21, 2012: Cetraria ericetorum and Flavocetraria cucullata

Cetraria ericetorum and Flavocetraria cucullata

Today's entry was written by BPotD work-study student, Katherine. She writes:

For today's entry we have two lichens, Cetraria ericetorum and Flavocetraria cucullata. Many thanks to Richard Droker (aka wanderflechten@Flickr) (Daniel adds: I believe the vascular plant in the image is Sedum stenopetalum).

Cetraria lichens are commonly known as Iceland lichens, Icelandmoss, or heath lichens. While Cetraria ericetorum is commonly known as Iceland lichen, Centraria islandica (as inferred by the name) is known as "true Iceland lichen", according to Brodo et. al.'s 2001 tome, Lichens of North America (hereafter referred to as Brodo, as he was the principal author). The USDA lists two subspecies of Cetraria ericetorum, Cetraria ericetorum subsp. ericetorum (cetraria lichen) and Cetraria ericetorum subsp. reticulata (reticulate cetraria lichen).

In Lichens of North America, Cetraria ericetorum is described as having a pale to dark brown usually-curled thallus (body) with narrow lobes 1-3mm across, which may become fused where the edges touch. However, according to the Lichen Flora of the Greater Sonoran Desert Region Vol. 1, it may be anywhere between 0.5mm and 8.0mm in breadth. Brodo goes on to describe Cetraria ericetorum as growing on the ground with grasses and heath, and, in order "to tell one species of Iceland lichen from another, look for the white pseudocyphellae [= "a tiny white dot or pore caused by a break in the cortex and the extension of medullary hyphae to the surface"] on the branches"." Furthermore, that "the lobes of [Cetraria ericetorum] are narrower [than Cetraria islandica], and [Cetraria ericetorum] never contains fumarprotocetraric acid".

The Consortium of North American Lichen Herbaria (linked above re: Sonoran flora) cites that Cetraria ericetorum is found on "soil and moss, or rarely on bark or wood" in "temperate [or] boreal areas of western North America from low altitudes to alpine areas and at high altitudes" (distribution map). Brodo shows a range further northwards into most Canadian provinces, with some gaps in northern Alberta and central Saskatchewan.

The second species present belongs to the genus Flavocetraria. Brodo characterizes them as small to medium-size, with pale greenish yellow to yellow colouring, having a smooth lower surface which is the same colour as the upper surface, without any rhizines or cilia and having white medulla ["internal layer of the thallus or lecanorine apothecium, generally composed of loosely packed fungal hyphae"]. He also notes their resemblance to the genus Cetraria, except for their colour, and note that "several species of Cetraria grow in the same habitat" as evidenced by this photo of the two growing together.

Flavocetraria cucullata may be "2-6 (-8) mm wide and 25-60(-80) mm high, ruffled at the margins, and curled inward, almost forming a tube (sometime fusing where the edges touch), often curving back at the tips [...] the base of thallus [may often become] red-violet". The species is found "on the ground among mosses and heath" and "in open conifer woodlands and tundra, usually at high elevations". Brodo also reports that Alaskan indigenous peoples incorporated this lichen as a flavouring for fish or duck soups.

The distribution map for Flavocetraria cullata is available via from the Consortium of North American Lichen Herbaria.

DigitalMycology.com provides several photographs which may help for distinguishing between Flavocetraria cucullata and Flavocetraria nivalis, a very similar looking lichen: Flavocetraria.

Jan 18, 2012: Bistorta bistortoides

Bistorta bistortoides

Today's entry was put together by Katherine. She writes:

Thank you Wayne Weber (Wayne Weber@Flickr) for today's photo of Bistorta bistortoides.

Bistorta bistortoides is commonly known as American bistort, western bistort, smokeweed, mountain meadow knotweed or dirty socks (a reference to the "fragrance" of the flowers). Scientifically, it is also known by these synonyms: Polygonum bistortoides and Persicaria bistortoides.

This perennial species ranges in height from 0.1m to 0.75m, although plants will tend to be shorter if they are growing at higher elevations within their range (1300m-3800 m).

Bistorta bistortoides is native to western North America and is distributed from British Columbia, south to California, and eastwards into Alberta and the central United States (Montana, Wyoming, Colorado, and New Mexico). The Jepson eFlora lists Bistorta bistortoides as being present in "wet meadows, streambanks and alpine slopes".

Bistorta bistortoides blooms relatively soon after snowmelt and fruits later in the summer. Although no uses are listed by the USDA, the Flora of North America (linked above) provides some traditional native uses: the "roots of western bistort were used in soups and stews by the Blackfoot, [and] boiled with meat by the Cherokee, and used in a poultice that was applied to sores and boils by the Miwok (D. E. Moerman 1998)". Wikipedia also notes that Bistorta bistortoides is "edible either raw or fire-roasted with a flavor resembling chestnuts. The seeds can be dried and ground into flour and used to make bread. They were also roasted and eaten as a cracked grain".

Jan 11, 2012: Iochroma cyaneum

Today's entry was assembled by Katherine:

Many thanks to JPierre@UBC Botanical Garden Forums for his pictures of Iochroma cyaneum. The first photograph is via the Botany Photo of the Day Submissions Forum, while the second was received via email.

Iochroma cyaneum, or violet churcu, is native to Ecuador and cultivated elsewhere. Gardeners in similar climates use them as evergreen ornamentals, while in harsher climates people grow plants outdoors in summer and use greenhouses or other structures to overwinter. According to Trade Winds Fruit, Iochroma cyaneum can flower year round, but will typically have more blossoms in the spring and fall. The Subtropical Horticultural Research Station has identified several cultivars of Iochroma cyaneum, with variation in flower colour distinguishing the cultivated varieties. Hummingbirds are known to be major pollinators of Iochroma.

In addition to violet churcu, Iochroma cyaneum is also known commonly as violet churur, blue cestrum and, in Swedish, pipviolbuske.

A relative of Brugmansia, or angel's trumpet, it shares the angel's trumpet's tendencies for toxicity (and, the same should be noted for many species within the Solanaceae or tomato family). All parts of Iochroma cyaneum are considered toxic, to the point where simply handling the plants may cause a reaction. Trade Winds Fruit notes that Iochroma cyaneum was traditionally used for medicinal purposes, as it is known to contain alkaloids and hallucinogens.

Jan 6, 2012: Hoya curtisii

Katherine is responsible for today's entry:

A big thank you to sandy130@UBC Botanical Garden Forums for today's image of Hoya curtisii. The accompanying text is from the original 1908 publication of the species in the Journal of the Asiatic Society of Bengal Pt. 2, Nat. Hist. 74(2): 563. This text was contributed to the Biodiversity Heritage Library by the Mertz Library of the New York Botanical Garden.

Hoya curtisii is native to the Philippines, Malaysia, and Thailand. Among hoyas, this species has some of the smallest leaves. Hoya curtisii is a relatively slow growing hoya with yellowish-green flowers with red centers. Descriptions of its fragrance range from citrus-like to smelling initially of fresh grass then, with age, more melon-like. Often used as an ornamental plant, particularly in baskets as it does not "climb or twine", plants of Hoya curtisii are tolerable to some drought, but not complete dryness.

The genus Hoya was named in honour of Thomas Hoy and comprises 200-300 species, which are commonly referred to as waxplants, waxvines, waxflowers, or hoyas. Studies at the University of Georgia found Hoya to be very capable of removing some indoor pollutants. Hoyas also exhibit Crassulacean acid metabolism (CAM) whereby plants reduce evapotranspiration by closing stomata in their leaves during the day, and collecting CO2 at night.

The book Medicinal Plants of Asia and the Pacific by Wiart (2006) provides insight to the traditional medicinal uses of some hoyas, including Hoya coriacea (used as treatment for asthma), Hoya coronaria (to induce vomiting, traditional use in Indonesia), and Hoya diversifolia (to ease the pain of rheumatism, used in Cambodia, Laos, Vietnam, and Malaysia). Methanolic extracts of Hoya diversifolia have also been shown to exhibit antinematodal activity.

Botany and mathematics resource link (added by Daniel): More on Fibonacci series today--a colleague had a question on branching patterns in saguaro cacti and conifers, which led him to find this neat project write-up he shared with me: The Secret of the Fibonacci Sequence in Trees, a Young Naturalist Award winner from the American Museum of Natural History.

Jan 4, 2012: Suillus paluster

Suillus paluster

Katherine is responsible for today's entry. She writes:

Many thanks to PietervH@Flickr for today's image of Suillus paluster.

Suillus paluster is commonly known as a red bog bolete, marsh bolete or swamp bolete, and is also scientifically known by these synonyms: Boletus paluster, Boletinellus paluster, Boletinus paluster, and Fuscoboletinus paluster. If searching for more information about it online, you'll get better results by searching for Fuscoboletinus paluster or Boletus paluster, as these names were in common use (and still persist) for many years. Suillus paluster was proposed in 1996, by Kretzer et al. in Internal Transcribed Spacer Sequences from 38 Recognized Species of Suillus sensu lato: Phylogenetic and Taxonomic Implications (Mycologia, 88(5): 776-785).

The caps of Suillus paluster are 2-7cm wide, broadly convex to plane or slightly depressed, and pale pinkish-purple to reddish-purple in colour. The pore surface is 1.5-3mm and pale yellow becoming more golden yellow and brownish with age, and does not turn blue when cut. The stalks are 2-5cm long and 3-7mm thick, and flesh is yellowish white to yellow in the cap, but reddish under the pileipellis and white in the stalk. Suillus paluster has a non-distinct odour and a mild or slightly acidic taste. Marsh bolete is found in sphagnum mosses under larch, throughout "eastern Canada south to Pennsylvania, west to Wisconsin". It is also associated with Pinus taiwanensis in Taiwan (PDF), and can additionally be found in China (Sichuan), Japan and the Republic of Karelia in Russia (where it grows in association with larch). Suillus paluster is edible, and fruits throughout August to November.

Dec 5, 2011: Colutea arborescens

Today's entry was written by Katherine.

Thank you James Gaither (J.G. in S.F.@Flickr) for today's photographs of Colutea arborescens (image 2).

Although the leguminous shrub Colutea arborescens is a native to Europe and North Africa, the species is now naturalized in some parts of the United States, Ontario (Canada), and China.

Colutea arborescens grows to be 1-2m in stem height, with bronze coloured bark and yellow flowers. The species blooms in the late spring and early summer, while the fruits develop in the summer. Fruits are brown or purplish, 2 to 3cm long, and dry into papery pods with 3 to 10 olive, brown or black seeds. According to Plants For A Future, the seeds are also poisonous, though the USDA lists the species as not toxic.

The genus name for Colutea arborescens comes from the Greek word kolutea which was used in antiquity for this group of plants, and the Latin word arboresco meaning "woody or tree-like" (literally to become a tree).

Colutea arborescens is commonly known as bladder senna, however they are not the real "senna" which refers to a genus in the same family; Fabaceae (Senna). Even bladder senna is used multiple times as a common name; native to Australia, the purple-flowered Swainsona colutoides, is also known by this moniker.

Colutea arborescens is used for ornamental purposes. The pods are used in dried arrangements, while the trees are cultivated for landscaping. Plants are also used for erosion control and as a revegetator in land reclamation, which is why in California, for instance, naturalized plants may be found in disturbed areas. Colutea arborescens has been known on occasion to become weedy in areas of cultivation.

Nov 28, 2011: Morchella esculenta

Morchella esculenta

Work-study student Katherine is the author of today's entry. She writes:

Thank you Marianne (aka marcella2@Flickr) for today's photo of Morchella esculenta.

Morchella esculenta sensu lato, or in the broad sense, is distributed globally. However, the "species" is taxonomically confusing, as explained by Michael Kuo: "The short version of the story is: the name has been confusing since it was created; it has been applied uncritically for centuries; and, here in North America, we have at least four genetically distinct candidates for the name (which represents a European mushroom that can't be compared to our mushrooms until someone figures all of this out)" (Michael has also posted a longer version). The species was originally described from collections made in Eurasia, and since this photograph is from The Netherlands, it may indeed be the true species as originally published. Then again, perhaps not; in "Species diversity within the Morchella esculenta group (Ascomycota: Morchellaceae) in Germany and France", a 2004 paper by Kellner et al. (doi:10.1016/j.ode.2004.07.001), differences in the internal transcribed spacer (ITS) region within the nuclear ribosomal DNA (nrDNA) of 22 different samples of Morchella esculenta s.l., suggested the presence of three distinct species.

The Royal Botanic Gardens, Kew has a species profile for Morchella esculenta that makes mention of the taxonomic difficulties of the group, as well as a detailed description of the fruiting bodies and spore deposits.

Species of this genus in general are collectively referred to as the morels or sponge mushrooms. The name of the genus is derived from the old German word Morchell, a term meaning edible fungus or morel, and the species name from the Latin esculentus meaning edible, or good to eat. Unsurprisingly, Morchella esculenta, or the common morel, is considered one of the best edible fungi, and highly sought after by mushroom hunters. Fruiting bodies of Morchella esculenta are noted by the Royal Botanic Gardens, Kew as being "quite nutritious, containing high-quality protein, and being rich in minerals and low in calories". However, all sources I've read also note that they must be cooked prior to consumption! Uncooked morels are known to cause digestive upsets. Morels showing signs of decay should also be avoided, as they can be poisonous. David Arora in his book Mushrooms Demystified notes that one should always "split them length-wise to check for millipedes, slugs, and other critters that like to hide inside". Despite these issues, morels "[are] so esteemed in Europe that people used to set fire to their own forests in hopes of eliciting a bountiful morel crop the next spring!" Morels may also be preserved by being canned, frozen, or dried.

The Wikipedia entry on Morchella esculenta claims that this fungus species has also been used in Chinese traditional medicines for the treatment of "indigestion, excessive phlegm, and shortness of breath". Recent laboratory studies (in rodents) have shown "anti-tumour effects, immunoregulatory properties, fatigue resistance, and antiviral effects" and "antioxidant properties".


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