Tag Archives: Botany

Garlic and octopus battle tree disease

Image: From Tacuinum Sanitatis, ca. 1400.

Image: From Tacuinum Sanitatis, ca. 1400.

For millennia, garlic, the ‘bulb’ of Allium sativum, has been used medicinally to help make humans better. Whilst many of these so-called ‘cures’ may be more fanciful than factually accurate, evidence-based medicine, there are studies that attest to the effectiveness of garlic or extracts thereof and therefrom against a range of human health-compromising bacteria and fungi (e.g. studies by Giles Elsom et al.Simon Woods-Panzaru et al. and Daniel Tagoe et al.). Indeed, so commonplace have such ideas become that garlic can be used as an educational tool investigating the anti-microbial effects of plant extracts. So much for humans: Is this relevant to looking after the health of, say, trees? Well, apparently so. In the battle against fungal diseases of trees, garlic has been mobilised with some success in Northamptonshire (a county in the east Midlands of the UK). Jonathan Cocking (Managing Director of Arboricultural & Ecological Consultants, JCA Ltd), whose company hold an ‘experimental government licence’ to engage in this work, use an allicin*-based solution administered directly to the base of trees. The solution is injected into an infected tree through eight pipes (the ‘octopus’ connection…) and transported throughout the tree via the transpiration stream. Apparently, ‘the moment the active agent starts to encounter the disease, it destroys it’, BBC Environment Correspondent Claire Marshall explains. Although details of the formula used are not forthcoming, it apparently uses organically-grown cloves from Wales, and somehow the allicin involved is stable for up to one year (rather than the usual 5–10 minutes’ lifespan of the molecule(!)). According to JCA’s website, their ‘Allicin/Conquer Project’ was started in 2009, and so far has had success against such fungus/oomycete infections as Bleeding Canker of Horse ChestnutSudden Oak Death,  Acute Oak Decline and Chalara dieback of ash. Although seemingly effective, widespread use of this treatment is considered impractical and expensive, and is unlikely to be used except to save trees of ‘historic or sentimental value’. It’s always reassuring to know that it’s still down to ‘value’(and that so-predictable human obsession with money/profit, etc…) as to which trees are allowed to die and which are worthy of being saved (in the UK, at least; I’m sure elsewhere in the world a much more enlightened attitude to saving trees prevails…). Anyway, let’s just hope the 10 finalists in England’s ‘Tree of the Year’ competition are in that ‘sufficiently worthy’ category should they succumb to some life-threatening infection, whether fungal or oomycete (or viral or bacterial or mycoplasmal or prionic, or …)!

* Allicin, ‘garlic’s defence mechanism against attacks by pests’.

[I expect it’s been considered (and ruled out), but, mindful of reports of viruses accompanying imported garlic and the fact that plants are attacked by a wide range of virus pathogens, one trusts that the Welsh allicin, as organic as it no doubt is, is sourced from virus-free garlic and doesn’t pose a virus-infection threat to the trees into which it is injected… – Ed.]

Prize-winning banana research

Image: Fir0002/Flagstaffotos, http://www.flagstaffotos.com.au.

Image: Fir0002/Flagstaffotos, http://www.flagstaffotos.com.au.

Readers of this blog will probably be aware of the high esteem/newsworthiness in which bananas (edible fruits, botanically a berry – a new snippet of information to me! – produced by several kinds of large herbaceous flowering plants in the genus Musa) are regarded. Well, in keeping with that musan leitmotif, here’s another banana-themed item. At the 24th First Annual Ig Nobel Prize ceremony in 2014, Kiyoshi Mabuchi et al. were suitably rewarded for their work investigating ‘why bananas are slippery’. Before this revelation elicits the anticipated “Eh? What?! They gave a prize for that??” reaction it should be pointed out that the Ig Nobel Prizes are awarded for achievements that make people laugh, but then think. In this case the Japanese tribologists’ work not only showed why banana skins are so hazardous (the comedic value of people slipping on discarded banana ‘skins’ has been known for generations), but also why apple and tangerine peel are not so ‘dangerous’. OK, so much for the ‘laugh’, what about the ‘thinking’? The team is interested in how friction and lubrication affect the movement of human limbs. The polysaccharide follicular gels that give banana skins their slippery properties are also found in the membranes in our own bodies where our bones meet and it is hoped that the botanical work will ultimately help in the development of a joint prosthesis. Banana research, going out on a limb?

 

[Ig Nobel Prizes (administered by Improbable Research) should not be confused with the more prestigious Nobel Prizes, whose list of prize-winners for 2014 didn’t include any banana-related research (so far as one could tell!). It is, however, noteworthy that Ig Nobels are presented for work done relatively recently; work that earns a ‘proper Nobel’ often takes years for it to be recognised. We would be interested to hear of any Ig Nobel Prize-winners who have gone on to win a Nobel Prize for their ‘ignoble’ work. Who’d have the last laugh then? Something to think about! – Ed.]

Timeless inner beauty…

Image: P. Cuttings’ personal archive.

Image: P. Cuttings’ personal archive.

When trying to appreciate something, it’s often remarked that it is the ‘inner beauty’ that’s important. In which case the plant cell biologists who probe the details within cells (and often illuminate them in all their glorious pin-point precision and fluorescent beauty with immunofluorescent techniques*) must not only, as scientists, be seekers of truth (for is it not writ, in scientia veritas?)  but also be true searchers after beauty. And if something’s really beautiful/true then it has a quality that transcends normal, mortal values and should be permanent. Is that correct? Well, the palaeopteridophytological work of Benjamin Bomfleur et al. may just be the definitive proof of that notion of transcendental permanence. Using language unusual for a serious, sober, scientific article, they describe the fossilised stem of a royal fern (family: Osmundaceae) in Lahar deposits (of putative Early Jurassic – Pliensbachian – date; 189.6–183 million years ago) from Korsaröd in Scania (southern Sweden) as having cellular details that are ‘exquisitely preserved’. Amongst the sub-cellular features discernible are parenchyma cells in the pith and cortex that show preserved membrane-bound cytoplasm, cytosol granules and putative amyloplasts (starch-bearing bodies). Furthermore, most cells contain interphase nuclei with conspicuous nucleoli! And – even more remarkably? – Supplementary Fig. S6 shows detail that is interpreted as signs of necrosis and programmed cell death(!). Whilst more importance is attached by the authors to the fact that the genome size of these reputed ‘living fossils’ has remained unchanged over at least 180 million years (and is understandably viewed as a ‘paramount example of evolutionary stasis’), the degree of internal preservation of cell contents is so good (see Figs S4 and S6 in the paper’s supplementary material!) I’m sure many extant workers could only hope to emulate such faithful preservation in their current work! So, not only is a thing of beauty a joy, it is a joy… forever (or 180 million years at least – long enough for you?). Somebody should write a poem about that!

* For a scientific haiku poem about this, may I humbly suggest the following? Page 15 at the Art Science Movement’s website.

 

[For an award-winning science journalist’s take on Bomfleur et al.’s Science paper, see Jennifer Frazer’s blog. Full-text of the paper – with supplementary pages – appears to be available in front of a paywall via the DiVA portal. And with apologies to our readers for the shameless self-advertisement by Mr P. Cuttings for his ‘poem’! – Ed.]

Better together…

Image: pixabay.com.

Image: pixabay.com.

No, this is not a belated bit of biased support for the Scottish referendum on independence from England  (which was rejected by those who voted and thereby prevented the United Kingdom becoming the anagrammatically amusing Untied Kingdom…). Rather, it is recognition that – at least in nature – sometimes things do work better when two partners co-operate rather than work against each other. Take for example the reef-building corals – an intimate mutualistic symbiosis between a unicellular alga, a dinoflagellate and an animal, the coral polyp. Put very simply, the alga provides much of the polyp’s food requirements by dint of its photosynthesis, which ultimately allows it to make the massive coral reefs. Although warm-water coral reefs are the basis of extremely rich and biodiverse ecosystems, they are nutritionally poor. This ‘nutrient paradox’ – originally recognised by Charles Darwin (is there any branch of biology that doesn’t have a contribution from this venerable Victorian?) – has traditionally been presumed to be due to very tight cycling/recycling of nutrients within the ecosystem (and the abundance of mutualistic symbioses therein, amongst other factors…). However, a new twist to this nutrient tale has recently been proposed by Orr Shapiro et al. They have revealed that, far from being static structures dependent upon the vagaries of currents to bring nutrients to them and remove waste products, the coral polyp actively generates micro-currents and eddies that promote nutrient inflow and exchange of materials. Using externally located cilia, these miniature structures whip up ‘vortical flows’ immediately adjacent to the epidermal surface, which reduces the exchange-limiting boundary layer at that site thereby facilitating mass transport between coral and the ocean. And in the way of all good discoveries, there are potential spin-offs to other areas of study. In this instance the team posits that investigation of these surface-situated cilia could be used as an alternative to the study of more-inaccessible, internalized cilia, e.g. those in the airways of animals. Thus, there may be unpredictable benefits for biomedicine from this photosynthetically dependent marine mutualism (I know, plants lighting up the path for others to follow – again!!). I’ve oftentimes wondered what the polyp brought to this relationship – aside from providing a chalky castle for the enslaved, hard-working alga. Well, I guess we now know, and it’s reassuring to discover (finally…?) that this intriguing symbiosis is much more mutual than we might previously have imagined.

 

[A video of this phenomenon can be seen on YouTube. The irony of internalization of the dinoflagellate symbiont – which, as its name implies, usually has flagella (two in this case, like much bigger versions of cilia)  – within the coral polyp and its consequential loss of its flagella on the one hand, and the importance of the polyp’s cilia (pale imitations of flagella?) in and to this relationship on the other, is not lost on Mr P. Cuttings. And this item gives a whole new meaning to the phrase ‘on the lash’ because cilium is Latin for eye-lash… – Ed.]

Thirsty? Then suck on a stone!

Golden gypsum crystals

Golden Gypsum Crystals from Winnipeg. Image: Rob Lavinsky/Wikimedia Commons

Whilst it is claimed that only the taxman can get blood out of a stone, it seems that some plants can abstract water from stone-like minerals.

Arguably, ahead of light, water is the most important abiotic factor that plants need and obtain from the environment. Although water is essential to plant life, it is not always available in sufficient amounts, and plants have evolved many adaptations that enable them to cope with water-limited environments – e.g. xerophytes in extremely arid areas, and halophytes in saline habitats. One strategy that was hitherto unrecognised is the extraordinary (I don’t think that’s too strong a word to use) ability of some plants to obtain large parts of their life-giving and -sustaining water from a mineral in the soil.

Analysing the isotopic composition of xylem sap in the rock rose Helianthemum squamatum, Sara Palacio et al. showed that it was similar to that of the water of crystallization in gypsum – CaSO4.2H2O, an inorganic mineral common in the plant’s environment. And, significantly, the composition of the water in the xylem differed from that of free water – i.e. that which is freely available within the soil (albeit in short supply!), the more usually assumed water source for plants. This therefore provided strong evidence that the plants were using the mineral as a water source – especially in the summer months when it accounted for 70–90% of the water used by these shallow-rooted plants.

Several other ‘coexisting shallow-rooted, sub-shrub species’ (the gypsum-specialist Lepidium subulatum – a gypsophyte – and the ‘non-specialists’ Linum suffruticosum and Helianthemum syriacum) behaved in an isotopically similar way to H. squamatum, suggesting that this phenomenon may be a widespread strategy of water-extraction by plants in this environment.

Although it is as yet unclear how the plants get hold of the water from this unusual source, it is suggested that high temperatures in the environment may cause the water to evaporate from the mineral when it can then be acquired by the plant.

Whilst this is a neat enough solution (pun recognised, but not intended!) for life on Earth, the authors conclude that ‘given the widespread occurrence of gypsum in dry lands throughout the Earth and in Mars, these results may have important implications for arid land reclamation and exobiology’. So, botanical research that may truly be ‘out of this world’!

[Intrigued by these intriguing gypsophytes? Then why not indulge your interest and read more of Sara Palacio et al.’s research in ‘Plants living on gypsum: beyond the specialist model’? – Ed.]

Strasburger’s Plant Sciences [Including Prokaryotes and Fungi]

rev-Strasburger2013BookCover

 

 

 

 

 

By Andreas Bresinsky Christian Körner, Joachim W. Kadereit Gunther Neuhaus and Uwe Sonnewald. Springer, 2013

One of my first botany memories was buying a second-hand copy of Strasburger’s Lehrbuch der Botanik – in German – and marvelling at the many images that illustrated that weighty tome. Attempts to translate passages of interest were painfully slow with my elementary science German, so I never managed to appreciate the text of that textbook. Whether that experience influenced me towards a career in botany we’ll probably never know, but it certainly left a lasting impression.

Eduard Strasburger – that book’s eponymous originator – was a Polish-German botanist and one of the most notable plant scientists of the 19th century. Amongst his many botanical achievements – which ranged from sexual reproduction to the ascent of sap – he is widely considered to be the founder of modern plant cell biology (Volkmann et al., 2012). However, one of his most enduring legacies is the textbook that still bears his name over 100 years since his death in 1912. As the present book’s Preface advises, Strasburger’s Lehrbuch der Botanik für Hochschulen was first published in 1894, and has “greatly influenced university teaching in Germany and neighboring [US English prevails throughout the text] countries, and its 36 editions also mirror the dynamic history of the plant sciences”. Although still published under Eduard Strasburger’s name, it has always been a “multi-author effort, and Strasburger himself invited his colleagues at the Botanical Institute of Bonn University as contributors to the first edition.” Having had my attempts to penetrate the German version of this iconic textbook thwarted, the opportunity to review an English language edition was one I didn’t want to pass up.

In keeping with Strasburger’s multi-author vision for the book (which is probably more in the nature of a project that has evolved since its authorship has changed several times during its 120-year existence), the present 1,302 paged text [hereafter referred to as Strasburger 2013] containing 1158 illustrations over two volumes is divided into four parts, each a reflection of the breadth of knowledge and interests of the author(s) responsible for their compilation. Thus, in Volume 1 we have Part I Structure by Gunther Neuhaus with four chapters entitled, Molecular Basics: The Building Blocks of Cells; The Structure and Ultrastructure of the Cell; The Tissues of Vascular Plants; and Morphology and Anatomy of Vascular Plants. Part II Physiology by Uwe Sonnewald covers Physiology of Metabolism; of Development; of Movement; and Allelophysiology [“the diversity of physiological relationships that plants have with other organisms” – p. 9 of Introduction]. Volume 2’s sections are Part III Evolution and Systematics co-authored by Joachim W. Kadereit and Andreas Bresinsky, with chapters on Evolution; and Systematics and Phylogeny. Finally, Part IV Ecology by Christian Körner, whose four chapters cover: Basics of Plant Ecology; Plant–Environment Interactions; Ecology of Populations and Vegetation; and Vegetation of the Earth. The second volume concludes with a Timeline, Sources [References] [which supplement further reading associated with individual chapters], and the Index. The first volume commences with a 10-page Introduction which considers such notions as what Botany is, what is life?, the special position of Biology, and classification and significance of plant sciences. Scattered throughout both volumes are 34 ‘Boxes’ [which provide more specialist information on such concepts as “Cell fractionation”, “Types of stele”, “Important units in photobiology”, “Thale cress: Arabidopsis thaliana”, and “Effects of CO2 on plant growth”], and 14 ‘Topical Insights’ [presumably the “additional contributions by renowned experts in the field” per the publisher’s flyer, and which range from Christophe Benning’s “Galactolipids and membrane remodelling” to “Forest structure and gap models” by Hank Shugart via “The origin and early evolution of flowers” by Peter Endress and James Doyle and “Leaf nitrogen: A key to photosynthetic performance” by John Evans].

I’ve reviewed several English language plant biology/botany texts over the years and in my view Strasburger 2013 is probably unique. For example, it takes a rather broad interpretation of the subject matter of plant sciences (yes, I note the use of this binomial rather than the term ‘botany’ in its German antecedants) to include algae (which is reasonable since green algal ancestors are probably progenitors of the true Kingdom Plantae), fungi, and prokaryotes. Whilst inclusion of eukaryotic fungi may also be considered reasonable in a botany text (they are not animals and are plant-like in some respects…), incorporation of prokaryotes is unexpected; although these organisms feature mainly in the Evolution and Systematics part of Strasburger 2013. Wisely anticipating that concern, the book admirably defends its stance in the Preface thus, “The inclusion of bacteria, archaea, and the various lineages referred to as fungi may not be justified from a phylogenetic perspective when dealing with plants, but is necessary considering the important evolutionary and ecological interactions between plants and these organisms”. I can’t argue with that.

Part I’s Structure and Ultrastructure of the Cell is a comprehensive section which is reminiscent of Gunning (2009) (but with coverage here of cell walls!). And both The Tissues of Vascular Plants, and Morphology and Anatomy of Vascular Plants chapters could give Esau’s Plant Anatomy: Meristems, Cells, and Tissues of the Plant Body (Evert, 2006) a good run for its money, and incorporate more detail than is common in competing general plant science texts e.g. Raven Plant Biology (Evert and Eichhorn, 2012) and Botany: An introduction to Plant Biology (Mauseth, 2014). Part II Physiology compares favourably with Plant Physiology (Taiz and Zeiger, 2010) and with the likes of Physiological Plant Ecology (Larcher, 2003) or Plant Physiological Ecology (Lambers et al., 2008). Part III’s systematics section is a substantial contribution extending from prokaryotes to the Plant Kingdom, and its angiosperm section alone is reminiscent of Judd et al. (2007). But, and intriguingly, the term Kingdom is used in place of the more usual (and more widely understood?) term Domain. Hence, Strasburger 2013 talks of 3 Kingdoms (Domains) (e.g. p. 680), which would probably confuse those of us who are used to viewing the living world as consisting of 5 kingdoms but subsumed within three Domains. And chapters in Part IV’s substantial ecology section also bear comparison with the texts of Larcher (2003) and Lambers et al. (2008), whilst the Vegetation of the Earth chapter is a near-encyclopaedic compendium of coloured photographic images of the planet’s varied habitats.

However, throughout the tome there is no great emphasis on molecular biology – in the sense of relating developmental or physiological phenomena to the genes implicated therein, so Strasburger 2013 is no competition for the likes of Plant Biology (Smith et al., 2010) or The Molecular Life of Plants (Jones et al., 2013) (nor even Taiz and Zeiger (2010) or Evert and Eichhorn (2013) in this respect). Although, Strasburger 2013’s scope is broader than the former three of those four texts, this seems to be a serious omission at worst; a missed opportunity at best. It is undeniable that the molecular-genetic dimension is an important – essential, indeed – component of our modern day understanding of plant biological processes and phenomena, especially at the sub-cellular and biochemical/physiological level, which are a major focus of Parts I and II. In this respect Strasburger 2013 probably doesn’t fully “mirror the dynamic history of the plant sciences” (2nd paragraph of Preface), and is therefore a little out of step with some of its major English-language textbook competitors. But, how serious a deficiency this will be viewed by potential readers of Strasburger 2013 will depend on what they want from a botany – sorry, plant science – textbook (and how happy they will be to pay £449.50 for this idiosyncratic text).

An interesting inclusion in Strasburger 2013 is the 3.5 pages of ‘Timeline’ [“a selection of important contributions to Plant Sciences (Botany) from their origins up to the year 2000”], which extends from Theophrastus’ Enquiry into Plants of c. 300 BCE to the end of the second millennium CE’s sequencing of Arabidopsis thaliana‘s genome by The Arabidopsis Genome Initiative. But why does stop at 2000? For a book published in 2013 you’d expect at least some mention of 13 year’s additional noteworthy botanical achievements post-2000 (they do exist). Or, at least, to extend the timeline until 2008, the year of publication of Strasburger’s 36th German language edition upon which Strasburger 2013 is based.

The 14 Topical Insights are a nice touch. Scattered throughout, but integrated within, the book’s 14 chapters (but, no, not one per chapter!), they reflect a similar development one has witnessed more generally in plant biology textbooks in recent years. In all cases they are an attempt to promote that all-important topicality that helps to ensure the book has that ‘cutting-edge’ feel and is appropriately up-to-date (which should ensure that it is recommended, bought and hopefully read). It was therefore good to read about scientists other than the books’ co-authors, and on a range of interesting and relevant topics. One that caught my eye was Todd Dawson’s contribution entitled “From where do plants take their water?” which examined the use of stable isotopes of hydrogen and oxygen in water in plant physiology/ecology. Because the ratios of the different isotopes vary in water molecules from different sources, and are in turn reflected in the isotopic composition of water within the plant, this approach can be used to determine which sources of water plants actually exploit in the environment. Although published too late for inclusion in Strasburger 2013, that piece seems to anticipate Palacio et al. (2014)’s revelation that certain plants use the water of crystallisation associated with the mineral gypsum as a major source of water. How insightful and topical is that!

The impressive 30 pages of 3-columned Index extends from the curiously spelt – and therefore alphabetically misplaced – “Aacetate [sic.]-malonate pathway” and “Aautotrophy [sic.]” to” Zygotene” and “Zygotic embryo”, and has entries listed under every letter of the alphabet. However, I found no mention in the index – which presumably also means no inclusion and coverage within the text* – of strigolactones [“chemical signals for fungal symbionts and parasitic weeds in plant roots” – Akiyama and Hayashi, 2006]. In view of Strasburger 2013’s inclusion of Fungi within its pages to emphasise allelophysiology, this omission is unexpected, and arguably difficult to defend (and incidentally impacts upon one’s view of the up-to-dateness of the 36th German edition of Strasburger…). Surprisingly also, since Strasburger 2013 features William Bond’s Topical Insight entitled “A world without fire”, and in view of the book’s strong ecophysiological dimension, the Index has no entry for karrikins (and which are presumably therefore not covered within the text*). Karrikins are “a group of plant growth regulators of the butenolide class found in the smoke of burning plant material”. They are therefore compounds which have considerable plant science interest and ecological significance, and – one would have thought – are ideal for inclusion in Strasburger 2013. But, and before this is challenged by those who – rightly – state that these compounds weren’t named karrikins (e.g. Chiwocha et al., 2009) until after the 2008 publication date of the 36th German edition of Strasburger upon which this English translation is based, their omission from this English edition is still an issue because it is quite clear that Strasburger 2013 is not constrained by that 2008 date. Supporting that view is Bond’s own Topical Insight which cites references from 2008, 2009, and 2010 (and e.g. Körner’s chapter 14 in Strasburger 2013’s main text includes several 2011 and 2012-published references). Which accords with the Publisher’s statement that Strasburger 2013 is based upon, and not a direct translation of, the 2008 German edition. With more optimism I also searched the Index for forisome(s), ATP-independent contractile proteins in the sieve elements of some plants (which are exciting interest because of their potential exploitation as a so-called biomimetic ‘smart material’). These sub-cellular structures were named shortly after the start of the current millennium by Knoblauch et al. (2003), and so well before the all-important year of 2008. Sadly, that term was not found either (and which presumably also indicates that any mention thereof is absent from Strasburger 2013’s main text*). What this comparatively simplistic scrutiny of the Index reveals is that, although some attempts to include more up-to-date references than the 2008 German Strasburger edition permitted have taken place (and which are laudable), and notwithstanding the inclusion of the Topical Insights with some post-2008 references, one should not infer that the whole of the main text is as up-to-date as its 2013 publication date suggests; Strasburger 2013 still seems largely rooted in the ‘noughties’. And these forisome, karrikin and strigolactone revelations are illustrative of the main issue I have with Strasburger 2013

This 2013 English translation is based on the 36th German language edition of Strasburger published in 2008. As the first English version since the 1976 translation of the 30th German Edition, Strasburger 2013 is to be welcomed. However, given that gap of nearly 40-years, and encouraged by having seen some attempts to update the text for researches/references post-2008, it seems a great pity that the publisher didn’t wait just a little longer to provide an English translation of 2014’s 37th German Edition of Strasburger (wherein one hopes such issues as forisomes, karrikins and strigolactones will have been addressed…). That tome should be as up-to-date as it can reasonably be expected to be and would arguably be a more fitting re-entry of Springer into the highly competitive English language plant science textbook market after an absence of nearly four decades. Given that English is not only a global lingua franca, but is also the international language of science, and that English is spoken by approx. 335 million people (cf. c. 78 million for German), one can’t help but think that a ‘Strasburger 2014’ (or even Strasburger 2015 – but don’t leave it any longer or we’ll have issues of Strasburger 2013 up-to-datedness again!) might have been a better way to extend – and expand? – Strasburger’s legacy beyond “Germany and neighboring countries” (2nd paragraph of Preface) by tapping into that much larger community of anglophone plant scientists, particularly in the USA.

References

Akiyama K, Hayashi H (2006) Strigolactones: Chemical Signals for Fungal Symbionts and Parasitic Weeds in Plant Roots. Annals of Botany 97: 925–931.

Chiwocha SDS, Dixon KW, Flematti GR, et al. (2009) Karrikins: A new family of plant growth regulators in smoke. Plant Science 177: 252–256.

Evert RF (2006) Esau’s Plant Anatomy: Meristems, Cells, and Tissues of the Plant Body: Their Structure, Function, and Development, 3e. John Wiley & Sons Ltd.

Evert RF, Eichhorn SE (2012) Raven Biology of Plants, 8e. WH Freeman.

Gunning BES (2009) Plant Cell Biology on DVD. Springer.

Jones R, Ougham H, Thomas H, Waaland S (2013) The Molecular Life of Plants. John Wiley & Sons Ltd.

Judd, WS, Campbell CS, Kellogg EA, Stevens PF, Donoghue MJ (2007) Plant Systematics: A Phylogenetic Approach, 3e. Sinauer Associates.

Knoblauch M, Noll GA, Müller T, et al. (2003) ATP-independent contractile proteins from plants. Nature Materials 2: 600–603.

Lambers, H, Chapin III, FS, Pons, TL (2008) Plant Physiological Ecology. Springer.

Larcher W (2003) Physiological Plant Ecology, 4e. Springer.

Mauseth JD (2014) Botany: An introduction to Plant Biology, 5e. Jones & Bartlett.

Palacio S, Azorín J, Montserrat-Martí G, Ferrio JP (2014) The crystallization water of gypsum rocks is a relevant water source for plants. Nature Communications 5:4660 doi: 10.1038/ncomms5660.

Smith AM, Coupland G, Dolan L, et al. (2010) Plant Biology. Garland Science.

Taiz L, Zeiger E (2010) Plant Physiology, 5e. Sinauer Associates Inc.

Volkmann D, Baluška F, Menzel D (2012) Eduard Strasburger (1844-1912): founder of modern plant cell biology. Protoplasma 249: 1163-1172.

*   NB this review based upon a limited-functionality ebook version of Strasburger 2013, which did not permit searching of the text.

Classical texts re-imagined/re-imaged…

Weird Scientific Equipment

Image: Stephen Hales, Vegetable Staticks. London, W. and J. Innys, 1727.

Do you remember the good old days when students read for a degree? Well, I don’t know how much proper reading they do these days – i.e. that which involves actually touching and turning the pages of a book or research article (but which is probably nowadays forbidden on health and safety grounds – well, you never know what disease you might pick up from a multi-accessed textbook… and paper cuts can really hurt…). But if their access to the real thing is limited it is heartening to know that some classic botany/plant biology-related texts are now available online as open-access items. So, by way of whetting your – and your students’ – appetites, here are a few I’ve stumbled across (another H&S issue with piles of textbooks, journals, manuscripts in one’s room…)…

Accordingly, first mention goes to that great ‘plant physiology’ text of 1727, Stephen Hales’ Vegetable Staticks, made available by the Biodiversity History Library. That important tome investigated such phenomena as root pressure and transpiration, and made such suggestions that ‘plants very probably draw through their leaves some part of their nourishment from the air’, and speculated that plants might use light as a source of energy for growth. At the time these were ground-breaking suggestions, but the fact that we take such ideas for granted nowadays is largely due to the work of such 18th century luminaries.

Other classic texts can be accessed free courtesy of the USA’s National Library of Medicine’s (NLM) TTP (Turning The Page) Online initiative, which is itself a development of the UK’s British Library’s own TTP system. But, ‘in creating our version of TTP at NLM, we have refined the original technology by using advanced 3D computer generated imagery, digital image enhancement, animation, illumination models and software programming to simulate the act of easily flipping through virtual books displayed in a highly photorealistic manner’. To see how close this is to the real thing, you are welcome to browse such timeless classics as Robert Hooke’s 1665 Micrographia. Lauded as ‘the first scientific best-seller, inspiring a wide public interest in the new science of microscopy’ [an essential discipline for unlocking plant structure, hence physiology, etc. – Ed.], it is also notable for coining the biological term cell.

If ethnobotany is more your bag, then there’s Elizabeth Blackwell’s 1737 A Curious Herbal. This charming publication includes hundreds of colour images of plants, many drawn from London’s Chelsea Physic Garden. Drawn by Elizabeth, the illustrations are accompanied by text supplied by her medically minded husband, from his debtors’ prison cell, and before he was ultimately decapitated for international conspiracy (! I tell you, botany is so multi-faceted!). And there’s also The Edwin Smith Surgical Papyrus. Whilst it may not contain many botanic references amongst its treatments, it does at least have the great claim to fame of being the world’s oldest surviving surgical text (from approx. 17th century BCE), and was written on … papyrus (‘a thin paper-like material made from the pith of the papyrus plant, Cyperus papyrus’).

Also containing a gallery of images for each text, this NLM initiative is a lovely resource. And if it is primarily images you seek – to illustrate your teaching, etc. – then many of those in the Wellcome Images collection are now essentially copyright-free, for any usage, under a Creative Commons Attribution Only (CC-BY) licence. Wellcome Images ‘is one of the world’s richest and most unique collections, with themes ranging from medical and social history to contemporary healthcare and biomedical science’, and is of great value for providing those important historical dimensions to your lectures (and let us not forget that ‘we are where we are now because of where we’ve come from’ – Anon.), e.g. on plants-and-people or other worthy topics.

Finally, for some insight into the old-fashioned ‘world-at-your-fingertips-before-the-digital-age’, a recently completed project gives us a chance to explore the library that accompanied Charles Darwin as he travelled the world aboard the Beagle. Will all – or any – of this rekindle interest in proper books? I do hope so!

One hundred and twenty-five years of the Annals of Botany

The first issue of Annals of Botany, August 1887 By August 2012, the Annals of Botany had been published without a break for 125 years. In that time it has become not only the world’s oldest continuously published botanical title but one that has retained a high international standing despite the emergence of numerous popular and well-run competitors. A recent article in the journal is the first of two that, together, look back over the Journal’s long history.

The article describes how the Annals of Botany first came into being in 1887 and the evolution of its editorship and management over the 50 years to 1937. These developments are described in terms of the people involved, how they organized the starting of the Journal and how they ran and financed it on a not-for-profit basis. The article pays particular attention to the lives of the nine remarkable and mostly rather grand individuals who founded the Journal and who, for the most part, came from privileged backgrounds. Despite being a youthful group (all but one were under 40), most were already establishment figures by 1887, e.g. Fellows of the Royal Society (FRS) or directors/professors of prestigious establishments, while the others were soon to become so. The article also outlines the academic environment which allowed the founders and their vision of modern botanical science to prosper, and describes a notable clash of personalities that almost brought the Journal down after only 12 years. In addition, accounts are given of the creation of the ‘Annals of Botany Company’, the effects on the Journal of the First World War and its aftermath, and how the Journal’s managers looked to the future by planning a ‘New Series’ starting 50 years after its foundation.

Jackson, M.B. (2015) One hundred and twenty-five years of the Annals of Botany. Part 1: the first 50 years (1887–1936). Annals of Botany, 115(1), 1-18

Tinted plates used to illustrate early issues of the Annals of Botany

Tinted plates used to illustrate early issues of the Annals of Botany

 

Brilliant bird-brained bryophyte diaspore diaspora…

many mosses

Ernst Haeckel, Kunstformen der Natur. Leipzig and Vienna: Verlag des Bibliographischen Instituts, 1904.
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There is an ancient and time-honoured association – maybe co-evolution even – between birds and flowering plants, e.g. in respect of pollination and dispersal of the fruits/seeds of the latter by the former. Now, at the other end of the evolutionary spectrum of the Plant Kingdom, is news of another avian–Plantae link-up as Lily Lewis et al. present evidence for long-distance transport of bryophyte ‘bits-and-pieces’ in the plumage of transequatorial migrant birds.

Bryophytes – a general term that embraces mosses, liverworts and hornworts – are so-styled ‘lower plants’ that have occupied the planet for megamillennia and have many important ecological roles. But, like the other members of the Plant Kingdom, bryophytes are essentially immobile and fixed to one location. This poses problems to any enterprising moss, etc., that wants to boldly go, seek out, occupy and colonise new areas, in order to command resources and help to ensure its survival in the dog-eat-dog jungle that is the natural world.

However, evolution has equipped these cryptogams with a phase of the life cycle that is potentially mobile, the spore stage. Transfer of those spores away from the parent plant – and their subsequent germination, establishment and development into individual bryophyte plants – reduces competition for resources between parent and offspring, and extends the area occupied by that species.

Consequently, exploiting agents that can contribute to wide-ranging dispersal of those spores represents a considerable boost to aspirations of territorial gain for an ambitious ‘lower plant’. But reliance on spores to spread the species can be risky; e.g. if the bryophyte taxon concerned is dioicous and it either doesn’t travel along with another spore that gives rise to, or to a place that already contains, the corresponding male/female gametophyte in the new neighbourhood. Which is why Lewis et al.’s work is of considerable interest because – and despite the headline in Scientific American’s news item on the subject – the bird-assisted moss migration is not really about spores, but diaspores.

Although a diaspore (or ‘disseminule’) can be defined as ‘a reproductive plant part, such as a seed, fruit, or spore, that is modified for dispersal’, the definition is usually broadened to include any plant part that could result in the establishment of a new individual. Thus, it includes not only bryophyte spores, but also fragments of established plants, too.

Sampling the plumage of bird species in their Arctic breeding grounds – prior to their South Pole-ward migration – the team found examples of diaspores not only of bryophytes, but also of green algae/cyanobacteria, and fungi. The presence of these putative propagules amongst bird feathers thus seems to establish this phenomenon as another instance of ectozoochory (transport of plant – and algae/fungi/bacteria! – propagation units on the external surface of an animal).

But just because these passengers may be present at the start of the journey doesn’t necessarily mean that they arrive at the carrier’s destination, which in some cases – such as the red phalarope and the semipalmated sandpiper – is the southernmost tip of South America; e.g. could the disseminules be consumed during preening as a sort of in-flight snack by the birds…?

And – as the investigators recognise – even if diaspores arrive, this doesn’t demonstrate that they are viable and could become established in the new home. But it’s another step towards unlocking the mystery of how the disparate bipolar distributions of certain taxa of bryophytes, etc. could be established and maintained. Whether this counts as ‘blue-skies’ research I’m not sure, but it’s a topic that’s certainly got legs and could well take off!

[And if you’re interested in seeing of some of the pre-publication comments on the bryophyte paper, they can be found online. And for more on the world of moss, I recommend Jessica M. Budke’s blog site. – Ed.]

Phylogeny and biogeography of wild roses

Phylogeny and biogeography of wild roses The genus Rosa (with 150–200 species) is widely distributed throughout temperate and sub-tropical habitats from the northern hemisphere to tropical Asia, with only one tropical African species. In order to better understand the evolution of roses, this study examines infrageneric relationships with respect to conventional taxonomy, considers the extent of allopolyploidization and infers macroevolutionary processes that have led to the current distribution of the genus.

The ancestral area reconstruction suggests that despite an early presence on the American continent, most extant American species are the results of a later re-colonization from Asia, probably through the Bering Land Bridge. The results suggest more recent exchanges between Asia and western North America than with eastern North America. The current distribution of roses from the Synstylae lineage in Europe is probably the result of a migration from Asia approx. 30 million years ago, after the closure of the Turgai strait. Directions for a new sectional classification of the genus Rosa are proposed, and the analyses provide an evolutionary framework for future studies on this notoriously difficult genus.

Fougère-Danezan, M., Joly, S., Bruneau, A., Gao, X. F., & Zhang, L. B. (2014) Phylogeny and biogeography of wild roses with specific attention to polyploids. Annals of Botany, December 29, 2014, doi: 10.1093/aob/mcu245