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March 31, 2008
Hippophae rhamnoides
Again, another thanks to Connor for assembling this series:
Here is the last of four entries featuring a plant from the Global Facilitation Unit for Underutilized Species. Another four part series will be posted in the future. Photo courtesy of Paul Bordoni. Thanks again Hannes and Paul for all the information and photographs!
Hippophae rhamnoides, native over a wide area across Europe and Asia, is one of the important natural resources growing from Europe to northwest China. It can grow in low rainfall areas of mountains, sea coast and semi-desert areas. In western and northern Europe, it is largely confined to sea coasts where salt spray from the sea prevents other larger plants from out-competing it due to its tolerance to high levels of salinity. Sea buckthorn is dioecious, with separate male and female plants. It produces small flowers and red to yellow berries the size of a pea.
For centuries, the people of central and southeastern Asia have used sea buckthorn as an agent of traditional medicine to prevent and treat various ailments. Today, the plant is primarily valued for its fruits, which provide vitamin C, vitamin E, and other nutrients, antioxidants, oils rich in essential fatty acids, and other healthful components. The leaves are also used for making a multi-vitamin herbal beverage. The list of products made with sea buckthorn is long and varied and includes jams, juices, medicinal and cosmetic lotions, nutritional supplements, liquors.
Medicinal uses of sea buckthorn are well documented in Asia and Europe. Clinical tests on medicinal uses were first initiated in Russia during the 1950s. The most important pharmacological functions attributed to sea buckthorn oil are: anti-inflammatory, antimicrobial, pain relief, and promoting regeneration of tissues. More than ten different drugs have been developed from sea buckthorn in Asia and Europe.
In large areas of northern China and Mongolia sea buckthorn has been developed into a major environmental resource. Many areas in fact, have become virtually treeless, even though they were once forested. Soil losses have been huge, and several previous attempts to grow various trees to hold down the soil have been unsuccessful. Sea buckthorn has turned out to be useful because it withstands severe weather and grows huge root systems in poor soil (and fixes nitrogen in the soil). For many animal and bird species, sea buckthorn is an important source of food or provides shelter.
The planting and maintenance of sea buckthorn is encouraged by local people in northern China and in Mongolia who can earn income from harvesting the fruits and other parts of the plant. In Nepal a partnership involving an international foundation, university research institutions, local community-based organizations, and practitioners of traditional Tibetan medicine, is working with a hospital and international businesses to build a sustainable program for the cultivation and sale of sea buckthorn in domestic and international markets. Local women's cooperatives have also been trained to harvest and process wild sea buckthorn berries.
Some producers/retailers/distributors
Posted by Daniel Mosquin at 8:28 AM | Comments (6)
March 28, 2008
Cnidoscolus stimulosus
The last photograph and write-up in the underutilized plants series will appear on Monday. Connor and I are still sorting out some details about the entry, a task made more difficult by the fact that I'm 2000km away from Vancouver and not online often. So, that's the explanation for today's exceptionally late entry! In the meantime, Connor has assembled this write-up:
Todays Botany Photo of the Day comes courtesy of Bruce Vanderveen aka duneaster@Flickr (original via UBCBG BPotD pool). Check out his collection of native plant photos from Florida.
Who could suspect this dainty member of the Euphorbiaceae of being such a menace? A flower has never looked so appetizing, bearing such close resemblance to a piece of floral confectionary from some wedding cake. However, with such suggestive common names as finger rot and tread softly, it's no surprise that this plant isn't found on cakes or in bouquets. As can be seen from today's image, Cnidoscolus stimulosus is covered in trichomes. In the case of Cnidoscolus stimulosus, these small hairs will irritate the skin upon contact. Regarding tread softly and other plants which possess such weaponry, Nancy C. Coile writes,
"The urticating hair or trichome has a bulbous and very fragile tip which breaks off at an angle and results in a perfect tool for piercing skin. Basically, the shaft of the hair resembles a glass tube due to the deposition of silica in the cell wall during formation (Thurston 1974). When the urticating hair tip is broken, it has the action of a hypodermic needle and injects the urticating substances which cause the intense pain and result in irritated skin rashes." (from Florida's Department of Agriculture - Urtica chamaedryoides Pursh: a Stinging Nettle, or Fireweed and Some Related Species - PDF).
Cnidoscolus stimulosus is often mistaken for the true stinging nettle, Urtica dioica. The latter has a near world-wide distribution while finger-rot is confined to the southeastern United States. As far as the urticating substances in Cnidoscolus stimulosus are concerned, I can only guess that they might include those found in Urtica dioica such as histamine, acetylcholine, and serotonin (from the previously mentioned article).
Posted by Daniel Mosquin at 11:03 PM | Comments (9)
March 27, 2008
Brosimum alicastrum
Connor Fitzpatrick continues his work on this series:
The third of four entries from the Global Facilitation Unit for Underutilized Species is Brosimum alicastrum. Thanks again to Hannes and Paul.
Maya nut is the seed of Brosimum alicastrum, a large tropical rainforest tree that belongs to the fig family. It is native to Central America, Mexico and the Caribbean. It is also called ramon nut, breadnut, ojoche, ox, ash, ujuxte, ojite, ojushte, ujushte, capomo, pisba waihka and masica. It was once abundant throughout Central America, but is now highly threatened and even extinct in parts of its range due to cutting for firewood and corn planting. The tree can reach up to 45 meters in height.
Maya nut is a wild-harvested forest product. It grows in naturally fertile rainforest soils and can be considered an organic product because no chemicals, fertilizers or pesticides are used. It is extremely high in fiber, calcium, potassium, folate, iron, zinc, protein and vitamins A, B, C and E. Maya nut is nutritionally comparable to amaranth, quinoa and soy; no wonder it was a staple food for the pre-Columbian Maya and other indigenous groups of Mesoamerica.
The fresh seed can be boiled and ground into a dough similar to corn masa, which is then often used for soups, tamales, tortillas, burgers and puree. Dry seed can be roasted and ground into a flour for use in drinks and baked goods. Stewed, the nut tastes like mashed potato; roasted, it tastes like chocolate or coffee and can be prepared in numerous other dishes.
One Maya nut tree can produce up to 180 kgs of food per year. A recent discovery is a Mexican Maya nut varietal from Merida which produces fruit in its 4th year. This is a vast improvement over unimproved varieties which tend to produce in their 8th year. Maya nut tolerates marginal soils and drought, making it an excellent species for reforestation in degraded sites. Once established, it requires no maintenance or inputs and a Maya nut tree will produce food and provide ecosystem services for over 150 years.
Maya nut seed has the potential to become one of the most economically important nontimber forest products in the world. This is due to several factors including high economic value and consumer demand, abundance, productivity, distribution, ease of harvest and processing, good nutritional and culinary qualities, provision of marketable ecosystem services includingcarbon sequestration, and protection of soil, watersheds and biodiversity. If managed correctly, consumer demand for Maya nut has the potential to slow and eventually reverse deforestation, loss of biodiversity, poverty, food insecurity and malnutrition created by conventional cropping systems in Central America and Mexico. Unfortunately, Maya nut has received little attention from agronomists and foresters and there is little information about sustainable harvest levels, genetics and population biology of the species. This jeopardizes the potential of wild-harvested Maya nut to provide sustainable livelihoods for rural forest dwelling communities.
The Equilibrium Fund is an international NGO working to rescue lost indigenous knowledge about the Maya nut in Central America and Mexico to help conserve rainforest, reduce poverty and improve food security. For this work, The Equilibrium Fund won the St Andrews Prize for the Environment in 2006 and the Equator Prize in 2007. Since 2001, The Equilibrium Fund has trained over 7000 women from 348 villages in Honduras, Nicaragua, Guatemala, El Salvador and Mexico. 5 women’s Maya nut producer groups comprised of over 400 member-owners now earn income and enjoy better health and nutrition by producing and selling Maya nut. Over 400,000 new Maya nut seedlings have been planted and hundreds of hectares of rainforest has been conserved as a direct result of The Equilibrium Fund’s work.
Some producers/retailers/distributors:
Posted by Daniel Mosquin at 12:00 AM | Comments (10)
March 26, 2008
Laurus nobilis
Connor Fitzpatrick continues his work on this series:
The second of four entries featuring underutilized species from the Global Facilitation Unit for Underutilized species is Laurus nobilis. Thanks Hannes and Paul!
Laurel is an extremely resilient evergreen forest tree that grows in all Mediterranean areas. In Syria, laurel grows wild above 200 meters over sea level along the coastal area. It is resistant to extreme temperatures and to coastal conditions. Its fruits are very dark, small, round berries that ripen between October and December.
In Syria, age-old methods handed down from generation-to-generation are used to produce unique products that are then sold in local markets. Although the local demand has remained stable for decades, export demand has grown recently, creating new income-generating opportunities for the local population. Laurel has been used for centuries in traditional cosmetic products such as laurel oil and laurel soap. Known for its unique perfume, it nourishes, softens, refreshes, and cleanses skin while acting as an antiseptic. It is especially recommended for sensitive and damaged skin. The oil is also used extensively in cosmetics and moisturizing products. In addition, dried laurel leaves are an important ingredient in Syrian and Mediterranean cooking. The leaves are also used in traditional medicine; dried leaves are brewed as an herbal tea and used to treat rheumatism, joint pains, schizophrenia, stress, to stimulate the appetite and as a sedative. The oil extracted from the berries is used as a cure for irritated skin, earache, asthma and urinary ailments.
For generations in Syria, the livelihoods of the community members in two coastal and mountain areas and of the traders in major Syrian cities have depended heavily on the production and marketing of traditional laurel products. Traditional collection and processing of wild laurel leaves and berries accounts for about one-third of their total yearly income. The market chain is made up of collectors, traders, soap producers and consumers. The collectors dry leaves and/or process the berries into oil; the traders buy the oil from the collector/processor and sell it to the soap makers who then produce traditional soap for the local market and for export.
In Syrian mountain communities, villagers collect laurel berries and manually extract the oil using traditional, multi-staged methods. The whole berries are boiled in water for six to eight hours in a metal container over a wood fire. As the oil rises to the surface, it is skimmed off with a wooden spoon then filtered and bottled. Sixteen kilograms of laurel berries produce about one litre of laurel oil. The quality of laurel oil depends on the fatty acid content which varies according to the variety of laurel used.
Laurel soap is believed to have been developed in Syria some 2,000 years ago. There are about 50 privately owned small-scale soap factories that use traditional soap-making methods. Most of the factories are located in the Aleppo Province. The soap is made with laurel oil, olive oil, and caustic soda using a process called saponification. The oil mixture is blended with an aqueous solution containing the soda in large cauldrons. This mixture is then heated to over 200 °C and stirred until the oil is reduced to glycerine and sodium salts. The caustic soda solution is drained from the cauldron and the soap mixture is left overnight to cool slightly; the excess water is then drained off. Once a solid block has formed, the soap is cut manually into square bars, stamped and stored in a dry place for at least six months. The process of making soap is carried out from November to April. From May to November, soap storage and trading activities are carried out.
A few retailers/producers/distributors include:
Posted by Daniel Mosquin at 7:03 AM | Comments (11)
March 25, 2008
Triticum dicoccon
Connor Fitzpatrick has assembled today's entry:
The next four Botany Photo of the Days are courtesy of Hannes Dempewolf, a graduate student in Botany, and Paul Bordoni, a member of the Global Facilitation Unit for Underutilized species. The photo and write-up are provided by the GFU. The GFU's mission is to "Promote and facilitate the sustainable deployment of underutilized plant species to increase food security and alleviate poverty among the rural and urban poor". Photo credit is courtesy of Clive Boursnell / Bioversity International (see comments below).
An unintended consequence of the green revolution has been a massive reduction in the number of species and diversity of crops. This process of crop replacement is a threat to local and global food security because the replaced indigenous crops often are essential for low input agriculture, have unique nutritional and cultural value, and contain a diversity of locally adapted genotypes with resistance to a wide array of biotic and abiotic stresses. Global climate change and degradation of once-productive lands have further heightened the demand for crops that perform well in harsh and/or changing environments. Research on neglected and underutilized species is needed to work towards a sustainable solution for increased food security and poverty alleviation as stated in the United Nations Millennium Development Goals.
Underutilized Species contribute to livelihood improvement by:
- increasing incomes
- ensuring food security
- improving nutrition
- enhancing biodiversity
- withstanding stress conditions
- occupying important ecological niches
- being produced with low external inputs
- stabilizing ecosystems
- creating new markets
Emmer wheat is one of the three hulled wheats known in Italy as farro. It is a low-yielding awned wheat, and was one of the first crops domesticated in the Near East. Once widely cultivated in the ancient world, it is now a relict crop in marginal mountainous regions of Europe and Asia. Its value lies in its ability to give good yields on poor soils, and its resistance to fungal diseases such as stem rust that are prevalent in wet areas. Its main use is for human food, though it is also used for animal feed. In recent years, farro has been enjoying a resurgence in popularity among gourmets and the health-conscious, who sing the grain’s praises for its high nutritional value and adore the hearty, flavorful taste of the “Pharaoh’s Wheat”.
Rich in fiber, protein, magnesium, and vitamins, emmer contributes to a complete protein diet when combined with legumes, making emmer grains and pastas ideal for vegetarians (or for anyone simply looking for a plant-based high-protein food source). Emmer is grown in Morocco, Spain, the Carpathian mountains on the border of the Czech and Slovak republics, Albania, Turkey, Switzerland and Italy. Italy is an interesting case as, uniquely, farro cultivation is well established and even expanding. In the mountainous Garfagnana area of Tuscany, farro is grown by farmers as a GI (Geographical Indication (also see: Relevance of geographical indications and designations of origin for the sustainable use of genetic resources (PDF))), with its geographic identity protected by law. Production is certified by a co-operative body, the Consorzio Produttori Farro della Garfagnana. GI-certified farro is widely available in health food shops across Europe, and even in some British supermarkets. The demand for Italian farro has led to competition from spelt, a non-certified farro, grown in lowland areas.
Wild emmer wheat is the immediate progenitor of tetraploid and hexaploid cultivated wheats. It is recognized as a source of genes for agronomically important traits. These include genes for large spike and grain size, high grain and protein yield, desirable composition of storage proteins, photosynthetic yield, herbicide response, salt tolerance, disease resistance, profuse tillering, drought tolerance, and, presumably, genes for other quantitative traits. With the advent of, and easy access to, molecular genetics and breeding tools, wild emmer wheat is expected to contribute the full range of its diversity, in qualitative and quantitative traits, for a more sustainable wheat production, especially in the developing world. It is also valuable for its contribution in the safeguard of biodiversity.
Some producers/retailers/distributors:
Posted by Daniel Mosquin at 3:20 AM | Comments (6)
March 24, 2008
Narcissus minor var. conspicuus
I haven't shared many of my photographs over the past several months. In part, this is because I've been too busy to photograph — a situation I'm going to try to avoid in the future. You'll start seeing more of my photographs after mid-April and beyond, but in the meantime, here's one from last spring.
There have been a couple other Narcissus photographs on BPotD previously: Narcissus bulbocodium and Narcissus pseudonarcissus subsp. munozii-garmendiae. This photograph was an attempt with sunset backlighting.
It is difficult to find much about this particular variety of daffodil online, though it is recognized botanically by the Royal Horticultural Society in The International Daffodil Register. In the garden's accessions database, we list it as being native to Spain.
Posted by Daniel Mosquin at 10:56 AM | Comments (8)
March 21, 2008
Passiflora 'Coral Sea' (tentative)
Thanks again to Connor Fitzpatrick for today's write-up.
The passionflower is no stranger to Botany Photo of the Day. Daniel has already featured the genus Passiflora multiple times, writing on the fruit and the taxonomy of certain species (see Passiflora caerulea, Passiflora miniata, Passiflora alata, and Passiflora lutea).
Today's originally unidentified passionflower seems to look very much like Passiflora 'Coral Sea' (link to commercial site), so that's what we're calling it tentatively. 'Coral Sea', of course, refers to its brilliant pinky-red colour.
The genus Passiflora contains a high degree of variation in terms of flower morphology (as seen in previous BPotD posts), fruit, and vegetative features. The wide spectrum of these traits has led to a taxonomic nightmare in which the genus has been divided into 22 subgenera, and then further divided into sections, supersections, subsections, and series. The current taxonomy, set forth in 1938, is troublesome because at least 120 new species have been found / named since, and their placement into taxa has been somewhat improvised (from Phylogenetic relationships and chromosome number evolution in Passiflora). This article provides an analysis of the current taxonomic system of Passiflora based on chromosome number and chloroplast DNA. Atie et al. found that both of these features yield monophyletic groups and suggest a revision of the current taxonomy.
Bonatton et al. (A first molecular phylogenetic analysis of Passiflora - PDF) conducted a simliar study using molecular genetics to clarify the relationships within Passiflora, and to verify the legitimacy of the whole genus as a monophyletic group. Their findings, though inconsistent with the previous system, present a new taxonomy within Passiflora. Due to the incomplete sampling of all the subgenera and possibly an inadequate amount of genetic sequence data, Benatto et al. insist that more research must take place to answer the questions they originally set forth.
A great overview of the taxonomic history of Passiflora can be read via the Missouri Botanical Garden's Passiflora Research Network. If you're keen on more photographs, visit Passiflora Online.
The photograph and artwork were created by stanflouride@Flickr, aka Stannous F, a frequent commenter on BPotD and provider of interesting plant news stories. Thank you!
Posted by Daniel Mosquin at 11:00 AM | Comments (6)
March 20, 2008
Bombax ceiba
Connor Fitzpatrick is the author of today's entry:
Today's Botany Photo of the Day comes courtesy of dinesh_valke@Flickr (original image). Take a look at his set of additional excellent photos of Bombax ceiba!
Common names for Bombax ceiba, a member of the Malvaceae (also placed in the Bombacaceae), include Indian kapok, the red cottontree, and the simal tree. As dinesh_valke notes in the written accompaniment to his Flickr photo, the fruit of the simal tree produces a silk-like floss often used in pillows, cushions, and blankets.
Bombax ceiba is native to tropical Asia, temperate Asia, and parts of Australia. The trunk and stems of young trees are covered in sharp outgrowths to deter herbivores. I found sources claiming these are spines while others claimed prickles (see here for a clarification) — there is a difference! The mature trees often have wide buttresses for support.
Flowering occurs between March and April for three weeks and fruit is produced quite rapidly in a period of one month. The bisexual flowers require outcrossing for successful fertilization. Flowers of Bombax ceiba illustrate a few floral innovations required for specialized pollination. Raju et al., in Bat and Bird Pollination in Bombax ceiba (PDF), found that mature buds open at night, releasing a somewhat rancid odour. They are bright red, held upright on the tips of strong branches, and produce copious amounts of nectar. As noted, this pollination syndrome is indicative of two pollinators: birds and bats.
Among the many visitors to the tree (including bees, squirrels, and monkeys), Raju et al. observed that only bats and birds were pollinating the flowers. Many of the other animals were found to be detrimental to the pollination process, through florivory (flower consumption). The worst offenders, as seen in a picture from the article, were monkeys who would consume the nectar and half the flower, then nonchalantly toss the flower to the ground.
Posted by Daniel Mosquin at 9:00 AM | Comments (5)
March 19, 2008
Hordeum vulgare cultivar
Connor had originally written this as an entry for Monday, but I had already posted the Ouratea before he sent me this write-up — so I've altered Connor's write-up to reflect this.
Happy belated St. Patricks Day! Recognized worldwide by people wearing green, eating green, and drinking green, March 17 is the national holiday of Ireland. Among the many acts people perform to celebrate Saint Patrick, drinking Irish beer seems to be the activity exercised most piously. The quintessential Irish beer is most certainly Guinness, and its most important ingredient is malted barley.
Barley, or Hordeum vulgare, is a member of the Poaceae. Its genus, Hordeum, has a worldwide distribution. Barley is also a member of the same tribe as wheat, Triticum spp. and rye, Secale cereale — the Triticeae (note: this is not a family name, as it does not end in -aceae). Barley is the fourth most important cereal crop in the world, grown most abundantly in Canada, Germany, and Russia (from Biodiversity International). Its main uses are for livestock feed, beer, and human consumption, in the forms of bread, cereal, and —my favorite— miso. As with most other cereal crops, barley has been part of many breeding programs designed to increase crop quality and yield. In breeding programs, crosses are made between lines with desired traits (e.g., resistance to a particular pathogen or drought tolerance) with the aim of producing a new cultivar. Chemical and radiation-induced mutations are also used to produce new, more resistant barley lines (a review of biotechnology and barley in Turkey (PDF)). Barley is already more tolerant of harsh physical conditions than any other cereal crop. It can be found in artic and alpine latitudes, as well as very dry places such as Yemen and parts of North Africa. Interestingly barley is also a very productive host for mycorrhizal fungi as shown by Chaurasia and Khare (Hordeum vulgare: A suitable host for mass production of mycorrhizal fungi (PDF)). This symbiotic ability may give barley an advantage over other cereal crops in less than favorable conditions.
Barley was domesticated around 10,000 years ago from Hordeum spontaneum in the area known as the Fertile Crescent. It is possible to trace its origins by looking at the genotypes of cultivated plants and comparing them to the genotypes of wild plants of a particular site; the more similar they are, the more likely it is that the cultivar came from that wild line. The article On the origin and domestication history of barley outlines the development of barley as a cultivated crop in the Fertile Crescent by genetic analysis and suggests that Hordeum vulgare is the product of only one domestication. A second article, Genetic evidence for a second domestication of barley (PDF), provides evidence for a second domestication east of the Fertile Crescent, accounting for barley lines in central and east Asia.
Thanks to stephenbuchan@flickr for the photograph (original via the UBCBG BPotD Flickr pool), even though it was taken in Scotland and not Ireland.
Posted by Daniel Mosquin at 7:15 AM | Comments (4)
March 18, 2008
Sarcocapnos enneaphylla
UBC Botanical Garden Horticulturist Jackie Chambers is the author and photographer behind today's entry. Thanks Jackie!
I never came across any wolves while looking for plants in El Barranco de los Lobos (“The Valley of the Wolves”) but I did find some lovely shoes.
In Spanish, the common name for this little plant is Zapatitos de la Virgen, which literally means “Shoes of the Virgin”. I spotted these “little shoes” clinging to a rock face while working in the Andalucia region of Southern Spain (read more about the diverse landscapes of this region).
Sarcocapnos enneaphylla is an unusual member of the poppy family. It is endemic to central and eastern Spain, as well as the eastern Pyrenees. This low growing perennial is a chasmophyte — a plant adapted to growing in crevices, be it natural rock faces or cracks in the walls of old buildings.
The species name enneaphylla means nine leaves or leaflets, and is appropriate as the blue green leaves are often 2 or 3 times ternatisect (or cut into three lobes). Each leaflet is 6-7mm in diameter. The foliage can be quite fleshy, and sunken in to form a shallow cup shape. The terminal leaflet is often reniform (kidney-shaped). The leaves are alternate along green fleshy stems, which can reach up to 15cm long, and are sometimes woody towards the base.
Flowering may occur thought the year; however the main flush is in the spring. Flowers range from white and yellow to pale pink and can be 8-10 mm long. The petals fuse into a tubular shape and create a small spur at the back of each flower. Fruit is inconspicuous and spherical (2-3mm.). This website has some detailed photographs.
Sarcocapnos enneaphylla can be very “plastic” — this is not a reference to any artificial components, but rather to the range in physical appearances. Members of the same population can look very different depending on the conditions they grow in. Individual plants can range from 4 to 30cm in diameter. Features such as petiole length, leaf texture and leaf fleshiness can vary greatly depending on the amount of sun exposure.
In the photographs above, the plant was growing in an exposed sunny site. As a result, the growth is very tight and compact, and the leaves are quite fleshy. Other photos of plants in more shaded locations will depict loose, spreading growth and thinner leaves (examples - browse for Sarcocapnos).
Posted by Daniel Mosquin at 11:11 AM | Comments (4)
March 17, 2008
Ouratea sp.
Connor Fitzpatrick is responsible for today's write-up:
Ouratea is a genus of tropical plants within the Ochnaceae. Ouratea is widespread throughtout the tropics, with species in places such as Costa Rica, Mexico, Brazil, Jamaica, and Kenya. Nine of these species can be found on the IUCN Red List, including Ouratea elegans — critically endangered and represented by a single individual. Hurricane disturbance is the major threat to this species, whereas the others are faced with habitat loss / degradation.
From the few images of the fruit of this plant available on the web, the individual in this photo seems to look like Ouratea lucens (via the Smithsonian Tropical Research Institute). This species spans Mesoamerica from Mexico to Colombia (from VAST specimen lists).
One species found quite abundantly in Brazil is Ouratea hexasperma. Within an area in Brazil known as the cerrado, Ouratea hexasperma, along with numerous other species, contribute to one of the most species-rich places in the world. The cerrado exhibits a range of ecosystems including grasslands, tropical forests, and many intermediate types. The plants found in the forested areas of the cerrado are frequently disturbed by wildfires. Medeiros and Miranda (PDF) recently investigated the ability of these plants (including Ouratea hexasperma), to survive and resprout after a fire. Exploiting the cerrado plants' natural tenacity may be a means of energy. In another article, Felfili and Vale (PDF) evaluated the use of the cerrado plants as a source of renewable energy, possibly in the form of firewood and coal. It's interesting to ponder the reciprocity between these two articles. The first examines the extent to which plants can resist the disturbance of fire and how they do this, while the second looks at the possible gain by completely incinerating them.
Thanks to Russian in Brazil@Flickr for a great photo from Brazil (via the UBCBG BPotD pool). See more photographs of Ouratea, as well as other Ochnaceae, in Russian in Brazil's Ochnaceae set.
Posted by Daniel Mosquin at 12:00 AM | Comments (6)
March 14, 2008
Beaucarnea recurvata
Apologies for the very late entry today — we were waiting for either of the final two entries for UBC Research Week. It looks like that won't happen, so we'll just move on. Connor Fitzpatrick wrote today's entry:
Beaucarnea recurvata is a slow-growing monocot evergreen tree in the Ruscaceae. Native to Mexico, it's distinctive features (PDF) include a swollen base capable of achieving considerable girth (2m) and clusters of long, slender leaves produced on branch tips. The graceful descent of the leaf clusters elicits the image of a pony's tail aimlessly swaying, hence the common name of ponytail palm. As a digression, my family was fortunate enough to befriend a miniature pony named Bonita, whom we would later adopt and bring home. A little less than fondly, I remember unsuccessfully dodging a few kicks in order to steal hairs to make a genuine ponytail paintbrush. Little did I know that the real treasures came from the backside of a camel instead.
Like all other monocots, the ponytail palm (incidentally not a palm at all), lacks true secondary growth. Its increase in girth results from cellular divisions of a secondary thickening meristem (STM). Note that this isn't a true secondary meristem, as monocots lack these (such as the vascular cambium or the cork cambium). This is akin to the true palms, such as the wax palm, which produce width by diffuse secondary growth where cells in older parts of the stem undergo division and primary tissue becomes lignified (also see Anatomy of Monocot Stems via Wayne Armstrong). Other monocots, such as the banana, have many layers of leaf bases and give the appearance of a thick trunk, but only have a primary thickening meristem. For more reading, here is an interesting article regarding tissue development in monocots.
Thank you to debham from Perth, Australia, for the wonderful photos via the UBC Botanical Garden Forums: thread 1, thread 2 and thread 3.
Posted by Daniel Mosquin at 7:50 PM | Comments (11)
March 13, 2008
Staphylea holocarpa var. rosea
The series for UBC Research Week is coming to a close soon. Connor's helped assemble this entry:
Andrew Riseman, an Associate Professor in the Faculty of Land and Food Systems at UBC and Ornamental Plant Breeder at the UBC Botanical Garden, shares his research on the various means by which plants can prevent self-pollination.
These photographs were taken from a research project evaluating self incompatibility in the genus Staphylea. Self-incompatibility systems act in promoting outcrossing (i.e., increasing genetic diversity) by only allowing non-self pollen to complete fertilization. These systems can be morphological (e.g., imperfect flowers where male or female organs are absent), developmental (e.g., protandry when the anthers reach anthesis before the stigmatic surface is receptive), or genetic (e.g., gametophytic self- incompatibility (GSI) where pollen tube growth of only self-pollen is disrupted by pistil tissue). In Staphylea, a GSI system appears to be present. These images are from outcross pollinations (i.e., compatible) between two Staphylea holocarpa var. rosea accessions maintained at the UBC Botanical Garden. As expected from a compatible cross, pollen grains successfully germinate and penetrate the stigmatic surface (photo 1). Pollen tubes continue to grow through the style to the ovary with individual tubes reaching separate ovuals (photo 2). Once fertilization is complete, fruit containing the newly formed seeds are produced (photo 3). The fourth photo shows a Staphylea flower post-anther dehiscence.
Posted by Daniel Mosquin at 9:14 AM | Comments (4)
March 12, 2008
Post-Fire Management of Forests
Connor Fitzpatrick continues with the series for UBC Research Week:
Scott Black is a Botany grad student at UBC. He is researching the ecological effects of post-wildfire management practices on the interior douglas fir forests, Pseudotsuga menziesii, of Southern British Columbia.
Disturbances such as forest-fires were once thought to be purely destructive forces, however, now they are seen in a more positive light. Disturbance (PDF) is now considered an important factor in maintaining the biodiversity of many natural ecosystems. Study of the effects of disturbance on plant community structure and, resource levels has initiated many ecological theories including the competitive exclusion and intermediate disturbance hypotheses. Disturbances are essential to ecosystem composition, function and sustainability but how much disturbance is too much?
Post-wildfire management in BC includes salvage logging, grass seeding and stump flipping. These practices increase the disturbance frequency and can potentially alter a plant community’s response after wildfire (here is a study, PDF, evaluating the effects of grass seeding). With 187 plant species and 98 animal species living in the interior douglas fir forests that are either red or blue listed (via the BC Ministry of Environment), an understanding of the effect of post-wildfire management practices on ecosystem health is crucial.
Salvage logging (PDF) can reduce the species diversity of plant communities, and reduce the number of tree seedlings after a fire. Soil loss / compaction and an increase in invasive species are results of salvage logging. Furthermore, the removal of burnt logs reduces the number of habitats for certain wildlife, especially birds, and can create unfavourable conditions for native understory vegetation.
In 2003, BC had a total of 2473 fires consuming 265,053 ha of forest (from the BC Ministry of Forests and Range), and fire frequency is expected to increase with climate change. Scott is comparing the plant communities found in post-wildfire sites that have been salvage logged, grass seeded, and left untouched. By uncovering the relationship between plant community structure, environmental characteristics and post-fire forest management practices Scott hopes to increase the sustainability of BC’s interior forests.
The first picture shows the ubiquitous post-fire species, Chamerion angustifolium, amidst a stand of burnt interior douglas firs. Fireweed has very deep rhizomes that sprout after fire and wind dispersed seeds that quickly cover burnt areas. It is also used as an ingredient in the cosmetic industry. This picture was taken in the McGillivray Fire north of Chase, BC last summer. The second picture shows the salvage logging process. The picture is courtesy of the Ministry of Forests and Range and was taken near MClure BC, North of Kamloops
(Adapted from Scott's 2007 proposal)
Here (PDF) is a report on wildfire management practices in western America.
Posted by Daniel Mosquin at 1:56 PM | Comments (7)
March 11, 2008
Chytriomyces sp.
The series for UBC Research Week continues. Today's write-up and photos are courtesy of Toko Mori. Toko writes:
My name is Toko Mori, a first-year graduate student in the Berbee Lab at the University of British Columbia. I study chytrid fungi, microscopic fungi that mainly live in freshwater. I especially focus on the local chytrids that parasitize freshwater microscopic algae. My long-term research goal is to create a tree of life of chytrids that parasitize algae and to see if there is any coevolutionary relationship between the species of parasitic chytrids and those of their host algae. I collected this chytrid on an alga, Vaucheria, from Burnaby Lake (Burnaby, BC) in August 2007. I have cultured it on agar and also co-cultured it with Vaucheria since then.
Since it seems that this is the first entry of chytrids in the Botany Photo of the Day, let me explain what they are. Chytrids are fungi, although they look quite different from mushrooms and molds, which we often think of as fungi. There are about one thousand species of chytrids which form the Phylum Chytridiomycota. Being the only group of fungi which reproduce by motile cells called zoospores (shown in picture 4), chytrids are considered to have diverged from the other fungi very early in their evolutionary history. Having motile spores gives them reproductive advantage in water. However, this is a double-edged sword; chytrids are unable to reproduce without moisture and thus bound to aquatic habitats.
Chytrids have recently attracted public attention as a cause for the population decline of amphibians. However, not all the chytrids are amphibian pathogens. To the contrary, many chytrid species are decomposers of organic matter in ponds and lakes, or parasites of microscopic invertebrates or algae, as in this case. Not much is known about their ecological roles.
Now let me explain these pictures. You are witnessing the moment of zoospore release, the highlight of their life history. The small round structure on the algal filament in picture 1 is a mature sporangium, where zoospores are produced. (The big bulge at the right end is a part of the alga, which I will explain later.) You can see the sporangium filled with small dots, each representing a zoospore. Five minutes later, the zoospores start to leave the sporangium, probably triggered by the sudden change in temperature caused by the intense light from the microscope. The change in pH of the surrounding water (when transferred from culture to a drop of distilled water on a slide) may also be the trigger. For a few minutes after the release, zoospores swarm just outside of the sporangium, until they start to swim away as in picture 3. As you may see in picture 4, the zoospores (ca. 4µm in diameter) have a flagellum like that of animal sperm. Eventually these zoospores stop swimming, retract their flagellum and encyst on a suitable substratum if they find one. Then they themselves will grow into a new sporangium, produce zoospores inside by mitosis, and start a new cycle of asexual reproduction.
A note for this alga. To co-culture this chytrid with its host, I received the culture of the host algal species, Vaucheria sessilis, from the Canadian Center for the Culture of Microorganisms at UBC. Vaucheria is unusual in that it lacks cell walls except when making reproductive structures; this entire filament seen here is one cell. The bulging end was formerly a spore, from which this algal filament grew.
Species identification is an important part of my research. Correct identification is the first step to making a tree of life. However, species identification of chytrids can be often difficult due to their simple body structure - there are not many morphological characters to study, at least on the light microscopy level. These days researchers combine molecular data and electron microscopy, together with traditional morphology. I have identified this chytrid down to the genus Chytriomyces, based on the light microscopic level morphology and molecular data.
Posted by Daniel Mosquin at 2:13 PM | Comments (13)
March 10, 2008
Amelanchier alnifolia
Connor Fitzpatrick continues with the series for UBC Research Week: Dr. Shannon Cowan is an Assistant Professor in the Faculty of Land and Food Systems. She shares her research today.
Dr. Shannon Cowan is conducting community-based plant research with B.C. First Nations in Nlaka'pamux Siska Band and Boston Bar Band.
Traditional food is associated with "healthy eating and living" in Aboriginal Canadian communities (here is an article, second from top, exemplifying this point). Current dietary practices in Aboriginal communities are also inextricably tied to cultural traditions and norms, which have seen significant shifts in Canada in the last few decades. Traditional food resources themselves are changing based on political and physical modification of environments including climate change, industrial development and contamination. There is a lack of research evidence regarding traditional food plant knowledge / beliefs and practices and how that affects traditional food consumption and health in Aboriginal communities.
Interdisciplinary research linking ecological knowledge, dietary knowledge and practices is needed to improve nutritional status in Aboriginal Canadians, and must be informed by an understanding of contemporary patterns of food procurement, preparation and distribution.
The Siska-UBC research team includes a Siska Community Research Committee (H. Michell, C. Michell, B. Munro, M. Williams), Siska Traditions Society Board Members, Siska Chief F. Sampson, UBC graduate student N. MacPherson, community member researchers and participants, and Dr. S.E. Cowan (UBC Faculty of Land and Food Systems, Botanical Garden and Center for Plant Research).
UBC-Siska Research Goal: Addressing health and education needs through community-based revitalization of Ecological Knowledge and Practices with Traditional Food and Medicine Plants.
Saskatoon (s/cáqw-m) has been identified as one of the dominant shrub species in the harvesting area under the Siska Forest and Range Agreement. Through the Traditional Knowledge for Health Research Project, the Siska-UBC Research Team is conducting cross-generational community-based research and education that involves this food plant resource through a traditional food survey (dietary interviews and traditional food guide creation), harvest training research and education, traditional food practices (berry jam making that bridges youth-elder generations), and a youth traditional food interview video project.
Concurrently there is a non-UBC project underway (Siska Researchers, M Keefer & Teal Jones Group) that is designed to test different strategies for enhancing saskatoon and other key cultural plant species on sites that have been in decline (see: Measuring success in managing for Saskatoon berries and other traditionally important plants). Timber management in the area, and the absence of traditional management techniques such as pruning and fire has been hypothesized as being directly related to the decline. Ecologically, saskatoon is known to be a key browse species (ungulates and bears), and some experiments have been designed to enhance the resource for wildlife habitat. However, there is a gap in the literature concerning management of saskatoon stands for berry production as a traditional food resource. Results of the UBC-Siska and the Keefer et al. projects will be integrated for economic and food security in Siska Band, traditional use plant species abundance, improved harvest yields, biodiversity and compatible management of forests for berries and trees, climate change mitigation and wildlife enhancement.
The first two photographs show saskatoon in fruit and flower, while the third shows M. Keefer working with a Siska youth.
Here (PDF) are the proceedings of a workshop, which included Siska Chief F. Sampson, at Royal Roads University concerning native plants and First Nation people
Posted by Daniel Mosquin at 9:27 AM | Comments (19)
March 9, 2008
Populus
Continuing the series for UBC Research Week, Connor introduces the next entry: Today we feature UBC Dept. of Forest Sciences Professor and Head, Robert D. Guy from the Faculty of Forestry. He shares with BPotD a collaborative project involving multiple labs.
Poplars Popular at UBC (an article from the Faculty of Forestry newsletter, Branchlines)
There is much interest in afforestation (PDF) as a strategy to help mitigate climate change by sequestering carbon and, ultimately, providing feedstock for renewable biofuels. These opportunities are likely to be greatest in intensively managed stands of rapidly growing trees. In Canada, there are several million hectares of marginal agricultural lands potentially available, mostly in the prairie provinces. But what’s actually available to plant? Not much it seems. Most of the available hybrid poplars currently planted in Canada are derived from species or populations adapted to relatively mild climates. While some of these "mild climate" clones are suitable to southern Ontario and southwestern British Columbia, few can survive on the prairies. There is, however, within our native forests, a tremendous untapped genetic resource, pre-adapted to the Canadian climate.
Ignoring aspens, Canada supports four of five North American poplar species. For example, balsam poplar is found in every province, from the US border to Inuvik, while black cottonwood occurs throughout British Columbia and adjacent areas of Yukon and Alberta. Appropriate selections and new hybrids could greatly increase the potential area that can be successfully planted to poplar.
Several researchers at UBC are studying genotypic variation in adaptive traits in poplar. To this end, some 750+ genotypes of balsam poplar (Populus balamifera) and black cottonwood (Populus trichocarpa), plus a wide selection of hybrids (including crosses with eastern cottonwood) are now springing up, in somewhat patchy fashion, at UBC’s Totem field (see photo). This “forest” might not last long, given the rate of campus development, but many of these genotypes grow so rapidly that if left uncontrolled there would be a continuous canopy within just a few years. Most of the clones come from two range-wide provenance collections – the BC MoF black cottonwood collection originally put together by Dr. C.C. Ying, and the new AgCanBaP balsam poplar collection compiled by scientists at the Prairie Farm Rehabilitation Administration (PFRA) Shelterbelt Centre, at Indian Head, SK. The AgCanBaP collection consists of some 15 individual clones from each of 43 populations.
So what are we doing with them at UBC? Several projects are underway or have been completed. In collaboration with Richard Pharis at the University of Calgary, Rob Guy and Shawn Mansfield (Faculty of Forestry) are investigating plant hormone profiles, fiber properties, carbon isotope composition, photosynthesis, and several other physiological parameters in black cottonwood, balsam poplar and various hybrids. This work forms the basis of thesis projects for Virginie Pointeau (Guy Lab) and Faride Unda (Mansfield Lab). In addition, Raju Soolanayakanahally (Guy lab) has been working closely with Dr. Salim Silim at the PFRA, both in Saskatchewan and at UBC, to characterize growth potential, photosynthetic rates, resource-use efficiencies and single-nucleotide polymorphism (SNP) variation in the complete AgCanBap collection. Using a subset of clones from the BCMoF collection, Hannah Buschhaus (Guy lab) recently completed her MSc thesis on variation in nitrogen isotope discrimination. Activity is not restricted to just the Faculty of Forestry. Quentin Cronk (Faculty of Land & Food Systems) and colleagues in Botany, for example, have been studying morphological variation, phenology and SNPs in the black cottonwood collection.
Physiology and other fancy stuff aside, the single most important attribute dictating the rate of biomass accretion is the length of the active growing season (i.e. the period from bud break to leaf drop). Timing of bud break in the spring is largely controlled by temperature. There is genetic variation in this trait but, in the main, when trees from different locations are planted in a common garden they generally flush out within a few days of each other. The same is generally true of cottonwoods, but a notable exception we’ve noticed at the UBC common garden is that trees from very high latitude can break bud in what we locally consider to be the depth of winter (December or January!). They also set bud several months too early (during our spring) because they are sensitive to the relatively short photoperiods encountered in Vancouver. Unlike bud break, bud set and (later) leaf drop are under tight photoperiodic control, and for these traits there are very strong latitudinal clines. In a common garden, genotypes from lower latitudes are in better synchrony with local conditions and remain active over a much greater portion of the available season, and they consequently accumulate far more biomass.
Although trees representative of northern populations generally do not grow as much as those from the south over any given summer, they can in fact possess higher photosynthetic rates. Indeed, they may also show the more rapid growth if measured over just a few weeks at the height of summer. We recently reported that light-saturated photosynthetic rates increased with latitude of origin in provenances of black cottonwood. This variation was well correlated with foliar nitrogen, stomatal conductance, and stomatal density.
The cline towards increased photosynthesis with latitude may be a generalised phenomenon among deciduous trees in North America. A similar trend is found in paper birch and Sitka alder and we see the same pattern in the AgCanBaP poplar collection. We speculate that northern provenances may have inherently high photosynthetic rates to compensate for the reduced leaf longevity associated with shorter growing seasons. Indeed, under an extended photoperiod in the greenhouse, where free growth is maintained, the fastest growing balsam poplar clones are from the far north. Clearly, the intrinsic growth rate must be assessed separately from the realized growth that occurs in a common garden. In other words, the largest individuals do not necessarily have the greatest growth potential if photoperiodic adaptation is unaccounted for. This raises the intriguing prospect of breeding trees from high latitude with trees of the same species from low latitude to combine high photosynthetic rates with a longer growing season. Using balsam poplar, such crosses have now been performed by collaborators at the PFRA and the “hybrid” progeny are undergoing assessment at Indian Head.
Posted by Daniel Mosquin at 12:19 PM | Comments (4)
March 8, 2008
Guizotia abyssinica
Fifth in a series celebrating UBC Research Week, again organized by Connor Fitzpatrick:
Scott Black, a Dept. of Botany M.Sc. student supervised by Dr. Gary Bradfield, and Hannes Dempewolf, a Ph.D. student co-supervised by Dr. Quentin Cronk and Dr. Loren Rieseberg, are researching the crop species noug, Guizotia abyssinica. Scott provided the photograph and Hannes adapted the write-up from this brochure on noug (PDF) that he co-authored (published by the Global Facilitation Unit for Underutilized Species).
What is noug?
Noug is an oil-seed crop, indigenous to Ethiopia and holds significant promise for improving rural livelihoods in Sub-Saharan Africa. The species is used in intercropping systems, grows on poor but also extremely wet soils, and contributes to soil conservation. While not fully domesticated, and suffering from low yields and susceptibility to insect herbivores, it contributes up to 50% of the Ethiopian oil-seed crop. Noug belongs to the Compositae family and is closely related to sunflower. It differs from domesticated sunflower mainly due to its high level of branching, numerous flower heads and small seeds. The oil content of noug seed varies from 30 to 50%. The fatty acid composition is typical for seed oils of the Compositae family with linoleic acid being the dominant component.
Ethiopia is well known as centre of diversity for several crops, including teff, enset and Ethiopian mustard. As a result, it has been suggested as Africa's independent origin of domestication. Noug diversity is greatest in Ethiopia and Eritrea and local farmers are able to distinguish many different land-races. The process of noug domestication is incomplete, probably due to frequent interbreeding with its co-occurring wild relatives. Apart from Africa (Ethiopia, Sudan, Uganda, Democratic Republic of Congo, Tanzania, Malawi, Zimbabwe), noug is also cultivated in parts of South Asia (India, Nepal, Bangladesh, Bhutan) where it was introduced several thousand years ago, and the West Indies.
The Rieseberg lab at UBC's Department of Botany is at the centre of an international collaborative research effort that has been launched in order to understand and manage the genetic diversity of noug for its improvement. The challenge of the project (2007-2010) is to show how modern molecular breeding efforts can be adapted and implemented for neglected and underutilized species, such as noug, through research on their diversity. This approach is especially powerful when conducted in the context of genomic information and tools that have already been developed for related major crops, in this case sunflower and lettuce.
This requires:
- collection, characterization and conservation of ecologically and genetically diverse germplasm
- initiation or re-orientation of existing breeding and crop deployment programs to capitalize on this diversity
- transfer of knowledge and technology to breeders and farmers in Ethiopia
With funds from the Canadian International Development Agency (CIDA), scientists from UBC's Department of Botany in collaboration with researchers from Addis Ababa University, the Ethiopian Institute of Agricultural Research and Bioversity International have initiated this project last year and have already completed several components, such as the collection and characterization of several noug cultivars in Ethiopia. Currently, scientists are working in the laboratory to assess the genetic diversity and population structure of noug and its wild relatives.
Posted by Daniel Mosquin at 11:38 AM | Comments (7)
March 7, 2008
Arabidopsis thaliana
Today's entry, organized by Connor Fitzpatrick, is the fourth in a BPotD series for UBC Research Week. The photographs and write up come courtesy of Dr. Fred Sack, Professor and Head, Department of Botany.
Each leaf contains thousands of pores, stomata, which allow gas exchange between the atmosphere and the shoot. Stomata are cellular valves central to plant survival because they allow carbon dioxide to enter leaves where it is used to make sugars in photosynthesis. Stomata are also adaptive because they close down when water loss becomes too great. Efficient gas exchange seems to require that valves be spaced apart from each other since it is rare in nature to find two stomata in direct contact.
My lab pioneered the discovery of genes required for stomatal formation and spacing. We first determined how stomata develop and are distributed in the model eudicot Arabidopsis. As in all plants, stomatal formation requires an initial division that is unequal in size and fate, generating a smaller cell and a larger cell. After the smaller cell becomes oval in profile, it divides equally thus producing the two young guard cells that develop into the stoma. Meanwhile the larger cell produced by the unequal division can in turn divide asymmetrically. Normally this “piggyback” (iterative) division is oriented so that the new small precursor cell does not contact the previously formed one, a placement that generates the minimal one-celled separation between stomata. This placement probably requires intercellular communication, a conclusion reinforced when we identified the TOO MANY MOUTHS gene which encodes a probable receptor. Defects in TMM induce spacing violations, suggesting that it normally receives spatial cues used to correctly orient “piggyback” divisions. TOO MANY MOUTHS acts exclusively in the cells that form stomata as shown by the distribution of green fluorescent protein in the accompanying picture (red shows the cell walls; note that stomata are still forming in this picture; reproduced from Nadeau and Sack, Science). Thus this gene, which is conserved in monocots as well, controls the division behavior of islands of stem cells distributed throughout the epidermis of the developing shoot.
We also found that a different gene, FOUR LIPS, is required to ensure that there is only one equal division of the GMC (the guard mother cell is a precursor to guard cells). Mutations in FLP induce extra, abnormal, equal divisions resulting in four guard cells (lips) in a row (“stoma” comes from the Greek for “mouth”). We found that FLP is a transcription factor that regulates genes involved in cell cycling. Additional genes in this pathway are being identified in collaboration with Erich Grotewold at Ohio State University. It is likely that restricting GMC divisions to one (failsafe) would be strongly selected for in evolution since the control of water loss and the efficiency of carbon dioxide uptake are critical for plant survival.
The first photograph was taken using cryoscanning electron microscopy. The second photograph was taken using confocal laser scanning microscopy. The red channel shows the cell outlines (cell walls labeled with propidium iodide), and the green channel shows where the gene TMM is expressed.
Posted by Daniel Mosquin at 10:09 AM | Comments (10)
March 6, 2008
Helianthus anomalus
Today's entry, organized by Connor Fitzpatrick, is the third in a BPotD series for UBC Research Week.
Loren Rieseberg, Professor and Canada Research Chair in Plant Evolutionary Genomics, conducts research on the genus Helianthus in his lab at UBC. Today's photographs of a hybrid sunflower species, Helianthus anomalus, are from the Little Sahara Sand Dunes in Utah, USA and taken by Jason Rick.
Prof. Loren Rieseberg has tapped the wild sunflower to explore a classic scientific question: How do new species emerge? To find out, his lab at the University of British Columbia marries molecular experiments with classic field studies to learn how radically different hybrid sunflowers arise and colonize new habitats.
Although scientists have long known that wild species hybridize — or mate with plants from different species — most believed that the resulting hybrids were maladjusted, evolutionary dead ends that quickly died out. However, over the past 15 years, Rieseberg has documented the rise of successful wild sunflower hybrids. His lab has compared the genes, physiology, and physical traits of five species: two widespread parental species, Helianthus annuus and Helianthus petiolaris, and three hybrid offspring that evolved between 60,000 and 200,000 years ago. Unlike their parents, the hybrid species — Helianthus anomalus (shown in the photos), Helianthus deserticola, and Helianthus paradoxus — favor extreme habitats: sand dunes, dry desert floor, and salt marshes, respectively.
To capture this evolution in action, Rieseberg's team replicated it by creating their own hybrids of Helianthus annuus and Helianthus petiolaris in the greenhouse. They analyzed the resulting neospecies for the adaptive traits — such as genes that confer salt tolerance or succulent leaves — needed to colonize the extreme habitats of naturally evolved hybrid species. Working with more than 2000 various synthetic hybrid seedlings, they successfully transplanted them in salt marshes in New Mexico and sand dunes or desert floor in Utah.
The DNA that drives hybrids is markedly different, too, Rieseberg and colleagues have shown. They used quantitative trait locus mapping — a method that taps molecular markers to find genes responsible for phenotypic traits such as leaf shape and seed size — to determine which combinations of alleles a plant has. Among sunflowers, the researchers confirmed that ordinary parent plants from temperate climates can indeed mate and yield hybrid offspring with hardier combinations of the same genes. These new gene combinations, they concluded, allowed the hybrids to colonize new ecological niches, such as salty and dry habitats.
From Brown, K. 2003. No garden-variety biologist. Science 302:1499.
Posted by Daniel Mosquin at 9:53 AM | Comments (9)
March 5, 2008
Laminaria setchellii
This entry is the second in a BPotD series for UBC Research Week, organized by Connor Fitzpatrick.
Dr. Rob DeWreede, Professor Emeritus in the Department of Botany, maintains a algae research lab at UBC. He provided today's photographs and write-up (note: the first photograph is courtesy of Dr. Colin Bates).
These photographs are of the kelp, Laminaria setchellii, a species of brown algae (Phaeophyceae). Both photographs were taken in Barkley Sound, which is located on the west coast of Vancouver Island, British Columbia, Canada. It is a region of much marine research, as it is adjacent to the site of the Bamfield Marine Sciences Centre, a research and teaching centre owned by three universities in British Columbia and two in Alberta.
Laminaria setchellii is a perennial seaweed, frequently found in the low intertidal and shallow subtidal zone, attached to rocks and, as here, intermingled with the seagrass Phyllospadix coulteri. As with all kelps, this macroscopic stage (the sporophyte) releases spores which germinate into separate microscopic male and female gametophytes, which in turn produce sperm and eggs, respectively. The egg, held on the female gametophyte, releases pheromones (chemicals which attract the motile sperm cells). The fertilized egg develops on the female gametophyte, overgrows the female gametophyte, and develops into a new diploid sporophyte phase.
Laminaria setchellii has been of interest to a number of students in the laboratory of Dr. DeWreede in the Department of Botany of the University of British Columbia. Ecological studies have included research on age structure and biomechanics of this kelp. Reports from the early 1900s suggested that some kelps had growth rings, and suggested also that these may be annual rings. We developed techniques that indicated that these rings are indeed formed annually, by much the same process responsible for the growth rings in trees. This knowledge opened a doorway of ecological investigation previously closed, e.g. research on age-related processes of these algae. We carried out research on the age distribution of populations of Laminaria setchellii under different ecological conditions, age-related reproductive effort, and age-related mortality. We discovered, for example, that individuals of Laminaria setchellii commonly live as long as 12 years, sometimes 20 – 24 years. Our studies on age-related reproductive effort enable us to test some hypotheses concerning reproductive effort in annual vs. perennial species of organisms, using seaweeds (research done by Terrie Klinger).
In addition, students in our laboratory have studied biomechanical properties of Laminaria setchellii, attempting to understand how these algae are able to tolerate the immense forces imposed on them by crashing waves generated by winter storms. For example, allowing for the greater density of water compared to air, crashing storm waves can impose forces equivalent to those generated by winds of 1000 km/hr! We investigated whether exposure to greater wave impact results in thicker stipes, larger holdfasts, or greater tissue strength, and the impact (on survival of Laminaria setchellii) of invertebrates such as crabs burrowing into the holdfast tissue (research done by Sophie Boizard). One conclusion from the data is that holdfasts of L. setchellii are “over-engineered”, as holdfasts of smaller diameter are attached with similar tenacity as larger holdfasts. However, if a holdfast segment is removed from the seaward-facing portion of the holdfast this results in significantly higher mortality than an identical segment removed from the lateral side of the holdfast. This result makes sense as a seaward-facing holdfast component experiences greater tensile stress than a lateral segment of the holdfast in breaking waves. Similarly, Laminaria setchellii holdfasts are asymmetrical, with more tissue allocated to seaward and shoreward parts of the holdfast.
Insights such as these are providing botanists and marine ecologists with a greater appreciation of the ways these fascinating organisms cope with some astounding physical forces, and how these apparently simple organisms can be used to test theories applicable to photosynthetic organisms more generally.
Posted by Daniel Mosquin at 9:02 AM | Comments (7)
March 4, 2008
Lotus japonicus and Lotus berthelotii
Connor's been gathering entries for a new series on BPotD, and it starts today. Connor writes:
Research Week has officially begun at UBC. This year's Research Week is particularly special as it marks UBC's 100th anniversary. Events are taking place from March 4-15 that celebrate the research conducted by all of UBC's faculties, departments, schools and partner institutions.
From March 4 to March 15, Botany Photo of the Day will feature research from the Department of Botany, the Faculty of Forestry and the Faculty of Land and Food Systems.
Dr. Quentin Cronk, a professor in the Faculty of Land and Food Systems and Director of the UBC Botanical Garden and Centre for Plant Research, shares with us today his research on the evolution of bird pollination:
These two photographs show two species of the legume genus Lotus. The yellow flower is Lotus japonicus, a “model organism” for legume biology. Its genome is being sequenced to aid the study of legume biology, particularly nodulation, the process by which legumes partner with nitrogen-fixing bacteria to produce their own fertilizer (a major source of nitrogen in the best agricultural systems). In order to separate the genetic components of nodulation, many mutants have been raised. You can see a fanciful animation of how these mutants are created and screened by the "magical mutation machine". Lotus japonicus, as the name implies, comes from Japan, but there are a number of closely related species throughout temperate Eurasia, including the familiar Lotus corniculatus (“bacon and eggs”) which is widely introduced in North America (and can be seen all over the UBC campus).
The red flower is a narrow Canary Island endemic called Lotus berthelotii, sometimes grown in warmer gardens under the name “parrot vine”. It makes a low, mounded, trailing bush with grey leaves. It looks so different from Lotus japonicus because it is bird-pollinated (Lotus japonicus, like most Lotus species, is bee pollinated).
The flowers are shown side-by-side to illustrate the different pollination mechanisms (for convenience the larger Lotus berthelotii flowers are shown the same size as the Lotus jaonicus flower). Bees are attracted to the flat upright “standard” petal of the yellow flower and land on the closed wing and keel petals, which they have to open to get at the pollen. In consequence the flowers are held horizontally. In Lotus berthelotii, ground perching birds probe down into the flowers from above and therefore the flowers are held in an upright position. Bird pollinated flowers are often red, both to attract birds and to help bird flowers avoid the attentions of bees. For animals like birds, with good colour vision, red contrasts well with green foliage. However, it is camouflaged from bees, as insect eyes are insensitive to the red end of the spectrum.
Together with graduate student Isidro Ojeda, my laboratory is investigating the evolution of bird pollination in Lotus and the gene expression changes that are associated with the very different flower type. The project fits well with our interest both in the evolution and biology of island plants and also in flower development. We are collaborating with the Jardín bótanico canario Viera y Clavijo in Gran Canaria and with Arnoldo Santos Guerra of the Jardín de aclimatación de La Orotava in Tenerife.
Incidentally, one mystery we have not yet solved is how we can persuade Lotus berthelotii to flower reliably in western Canada. Whether under glass or outside it remains stubbornly vegetative. We have tried hormone treatments, light treatments, various temperature regimes, not to mention various fertilizer treatments, and yet we only get the occasional flower here in Vancouver. In the Canary Islands, the plants are covered with flowers in April and May.
Posted by Daniel Mosquin at 9:29 AM | Comments (15)
March 3, 2008
Eremostachys laciniata
The first photograph for today's entry is courtesy of Amir A. from Israel (thank you for another contribution!). The remaining photographs, as well as the write-up, are thanks to UBC Botanical Garden horticulturist Jackie Chambers. Much appreciated once again! Jackie writes:
The upright stems of this perennial can reach 100-150cm high, but the most striking feature has to be the wooly texture — it's nearly impossible to look at this plant without stroking it. Sometimes called desert spike, Eremostachys laciniata occurs in fields and fallow land throughout Turkey, Lebanon, Israel, and Jordan.
The plant is well-adapted to life in the eastern Mediterranean — the leaves emerge after the winter rains, the flowers are produced in the spring, and by summer the whole plant has died back to the ground in order to avoid the heat.
The genus name Eremostachys is derived from two Greek words. The first is eremia, meaning “desert”. The second is stachys, which literally means “ear of corn”, but was a term instead used by the Greeks to describe the inflorescence of a particular group of plants: the genus Stachys (another member of the Lamiaceae). Those of you familiar with the genus Stachys will recognize the woolly texture and hooded flowers, and appreciate the literal Latin name of “desert stachys”. The species name is similarly descriptive: laciniata means “slashed or torn into narrow divisions”, and refers to the heavily lobed leaves.
The flowers are produced from March to May and are each 3-4 cm long. Flower colour can range anywhere from white to pale yellow, through to a pinky, purple brown. Just like the stems, the calyx is also woolly. The flowers are bilabiate, meaning the corolla is divided into “two lips”, a fused upper section of petals and a fused lower section of petals. Flowers are arranged in whorls along the flower spike, and the fruits are four single seeded units per flower, called nutlets. The flower and fruit shape are typical of the mint family.
Eremostachys laciniata is part of an interesting ongoing Israeli research project investigating the use of various native plants as possible cut flower crops. More photos of this attractive plant are available via the Flora of Israel.
Posted by Daniel Mosquin at 9:37 AM | Comments (8)
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Botany Photo of the Day and all associated images are licensed under a Creative Commons License.
Botany Photo of the Day is a project of the UBC Botanical Garden and Centre for Plant Research, located in Vancouver, British Columbia Canada. UBC BGCPR is a department of the Faculty of Land and Food Systems within The University of British Columbia.