Monthly Archives: May 2011

Genome jealousy

Image: Richard Wheeler/Wikimedia Commons.
Image: Richard Wheeler/Wikimedia Commons.

By way of a bit of an advertisement for the news site of another science organ – and to dispel any doubts that I am a complete techno-phobe – I’m happy to publicise information concerning recent plant-relevant DNA sequencing activities (originally sourced from the article by Hannah Waters at http://www.the-scientist.com/news/display/58161/), which includes: Leptosphaeria maculans (genome size: 45 million base pairs, MBP), a pathogenic ascomycete fungus that causes stem canker in members of the Brassicaceae (which family includes such important members as arabidopsis, oilseed rape and cabbages) (Thierry Rouxel et al., Nature Communications 2: 202; doi:10.1038/ncomms1189); Wheat stem rust fungus, Puccinia graminis (88.6 MBP), which includes the notorious Ug99 strain that is currently threatening global wheat harvests; and the unpopular Poplar leaf rust fungus, Melampsora larici-populina (101.1 MBP) (Sébastien Duplessis and co-workers, PNAS; doi:10.1073/pnas.1019315108). Unicellular autotrophs get a look in with Aureococcus anophagefferens (56 MBP), a harmful algal bloom (HAB) -causing pelagophyte (http://en.wikipedia.org/wiki/List_of_eukaryotic_picoplankton_species). Using an ecogenomics approach, Christopher Gobler et al. (PNAS 108: 4352–4357, 2011) reveal that the alga has more genes involved in light harvesting, organic carbon and nitrogen use than competing phytoplankton, which presumably helps it bloom and overwhelm the competition. Furthermore, genes for the synthesis of microbial deterrents are thought likely to further facilitate its proliferation with reduced mortality losses during blooms. And DNA-containing organelles are not overlooked: the chloroplast of Bryopsis hypnoides (153 000 base pairs), a siphonous green alga (Fang Lü et al., PLoS ONE 6: e14663; doi:10.1371/journal.pone.0014663, 2011).

Is the moss calyptra covered by a cuticle?

Is the moss calyptra covered by a cuticle?

Is the moss calyptra covered by a cuticle?

Over a century ago, the gametophytic calyptra was predicted to be covered by a cuticle that protects the sporophyte apex from desiccation. Budke et al. examine the moss Funaria hygrometrica using electron microscopy techniques and find that its calyptra is covered by a comparatively thick, multi-layered cuticle with cuticular pegs. The calyptra and its associated cuticle represent a unique form of maternal care that may have been essential for the evolution of the moss sporophyte.

Pollination shift in Neotropical Malpighiaceae

Pollination shift in Neotropical Malpighiaceae
Pollination shift in Neotropical Malpighiaceae

Flowers of Neotropical Malpighiaceae have a specialized pollination system in which floral oils instead of nectar are offered to attract oil-collecting bees. Cappellari et al. examine facultative loss of oil production by non-oil-secreting (eglandular) flowers in relation to pollination by bumblebees in populations of Pterandra pyroidea from the Brazilian Cerrado. They find that eglandular flowers represent a shift in the pollination system in which oil is being lost and pollen is becoming the main reward. This species thus exhibits an unusual transition from a specialized towards a generalized pollination system.

CO2 effects on reproduction versus vegetative growth

CO2 effects on reproduction versus vegetative growth

CO2 effects on reproduction versus vegetative growth

Increased atmospheric CO2 concentrations may affect competition for resources between reproduction and shoot growth in forest species. Han et al. examine mature beech (Fagus sylvatica) trees in masting and non-masting years with or without long-term CO2 enrichment and find that a reduction in shoot growth associated with masting is not observed under elevated CO2. Competition for resources is therefore reduced and rising atmospheric CO2 concentrations shift the balance of allocation witin the shoots.

Viruses and promotion of plant genotypic diversity

Viruses and promotion of plant genotypic diversity

Viruses and promotion of plant genotypic diversity

Genotypic diversity is essential for maintenance of plant species. Van Mölken and Stuefer examine White clover mosaic virus and Trifolium repens and show that the effects of virus infection on plant performance can differ greatly between distinct host genotypes, resulting in changes in relative fitness between virus-infected and control treatments. This suggests that virus infections may be of considerable importance for the maintenance of genotypic diversity in these host plants. FreeLink: PDF version linked here. (Link via authors names will be made free asap.)

Hay fever: another straw to clutch at?

Image: Steve Nova/Wikimedia Commons.

Image: Steve Nova/Wikimedia Commons.

As the northern hemisphere’s hay fever season gets into full swing, there is encouraging news from Mother Nature’s own medicine cabinet. Hay fever – ‘seasonal allergic rhinitis’ – is an allergic inflammation of the nasal airways, and the most common atopic disease in the industrialised world (10–25 % of that population are martyrs to the malady). It occurs when an allergen such as pollen is inhaled by an individual with a sensitized immune system, and is one of the most dramatic confirmations that spring has sprung and a botanical orgy of reproduction has begun. It is a miserable affliction that can cause sleep disturbance, impairment of daily activities, and poor performance in academic studies or other work, and those affected will try almost anything to be free of symptoms. The usual treatment is with anti-histamine drugs, but a randomised, double-blind, placebo-controlled trial by Alina Dumitru et al. (Journal of Allergy and Clinical Immunology; doi:10.1016/j.jaci.2011.02.045) demonstrates that Ze 339 (petasol butenoate complex) – extracted from Petasites hybridus, a member of the Asteraceae – combats nasal mucosa swelling faster and more effectively. Furthermore, Ze 339 also appears to have a preventative effect. And if this botanical equivalent of fighting fire with fire gets fellow sufferers hot under the collar at the prospect of better treatment, be advised that at present Ze 399 is only available on prescription in Switzerland and South Korea.

The End of the Botany Degree in the UK

Bioscience Education The last student enrolled in a pure “Botany” degree in the UK began in the University of Bristol this year, 2010. In recent years only the University of Reading also offered the Botany degree, before it was dropped there 3 years ago. This short article is written to draw attention to this fact and to a more general relative decline in the number of students pursuing degrees in plant science highlighted in a recent extensive report on the “Uptake of Plant Sciences in the UK” completed in 2009. We explore potential implications and causes by focusing on third level education, specifically full time degree courses as available through the UCAS application system. Findings are related to the preceding secondary school education and succeeding employment market that surround and influence the undergraduate experience.

Sinéad Drea, Department of Biology, University of Leicester, UK. The End of the Botany Degree in the UK. Bioscience Education 17-2 (2011)

Variation in floral scent post-pollination

Variation in floral scent post-pollination

Variation in floral scent post-pollination

Studies of the effects of pollination on floral scent and bee visitation remain rare, particularly in agricultural crops. Rodriguez-Saona et al. study highbush blueberry, Vaccinium corymbosum, and find that flowers left open to pollination have 32 % lower volatile emissions than those from which pollinators have been excluded. Field observations indicate that more bees visit bushes with pollinator-excluded flowers, suggesting that greater emissions of volatiles help guide bees to unpollinated flowers and thus increase plant fitness.

Book reviews and a poll – what about ‘bad’ books?

 

Books and Journals - current reading and for review

Books and Journals - current reading and for review

Development of thoughts or ideas, and dissemination of techniques or methods, happens not only in the pages of Journals or on the web, but in books too. Over the last couple of years, we have increased the number of book reviews in Annals of Botany, and put them prominently at the front each issue. For me, reviews have always been part of a lively Journal, and diversity makes them great to read – there is a place for the long, reflective piece, and for the short sharp blow-by-chapter (or should it be chapter-by-blow?) account. We have had free e-books reviewed, and I expect this category will increase. Our instructions have been strict in saying Annals of Botany “publishes reviews of current academic books”, but we are relaxing this criteria, and will use both AoBBlog.com and the Journal (with coverage in the blog too) to review popular books, texts and others where there is some link to botany.

 

I’m confident this is what I want to do, but now for the poll: what about bad books?

(Off-site voting at  http://poll.fm/30vqt)

I have used the answer options to give succinct thoughts about the pros of reviews of different qualities of books, but please feel free to amplify in comments! Stacked on my bedside table, along with journals, there are many review copies of books.  Two received recently, while not exactly bad, are not worth anyone’s time to read and there are better out there. One is a perfectly acceptable book on hybrid plant breeding written for a general audience, but I can’t imagine anybody enjoying reading or learning much from a volume that is entirely devoid of illustrations: even crossing and backcrossing schemes are described rather than drawn, and wild relatives are not photographed. The second book has a series of chapters with lengthy discursive reminiscences; at 10% of the length each would make a nice blog post once a month, but I (unlike the subject of Kenny Rogers’ The Gambler) would be hard pressed to say of the author, “in his final words I found an ace that I could keep.”

Do you want reviews to tell you why I’m not recommending these books, or should they disappear without trace? We have had a few reviews of ‘bad’ books: obviously, sometimes the opinion of the particular reviewer, but more often than not, the book has not reached the standard you would have hoped from the distinction of the editor or authors. I feel deceived by these, so want to see such reviews, although I have to say I would be reluctant to write such a review.
Anyway, with the following of AoBBlog, I’m looking forward to having some help in deciding what to review. As always, we welcome suggestions of books for review, particularly with the wide definition above with the option of going on AoBBlog.com – whether on paper, electronic, or free.

The ultimate packed lunch?

Heterotrophy or growing your own algae? Image: Scott Camazine/Wikimedia Commons.
Image: Scott Camazine/Wikimedia Commons.

Heterotrophy is so time-consuming: find prey, stalk prey, catch prey, consume prey… Preying all of the day and all of the night in some cases. How much more straightforward if you could just synthesise your own food and avoid all of that rushing about. Well, this particular calorific conundrum was solved by plants many hundreds of millions of years ago. But some animals have also cottoned on to this idea of a ‘free lunch’. Arguably, the most spectacular example of such an alliance is that between heterotrophic polyps and autotrophic zooxanthellae in coral reefs. Another – but entirely unsuspected – symbiosis has recently been discovered between the Spotted Salamander (Ambystoma maculatum) and a green alga (Oophila amblystomatis), within the adult reproductive tracts of the former, by Ryan Kerney and colleagues (PNAS 108: 6497–6502, 2011). An association between the alga and eggs of amphibians – and not just the spotted salamander – has been known for some time where it been suggested that the autotroph supplies oxygen to an otherwise hypoxic egg mass (e.g. Pinder and Friet, Journal of Experimental Biology 197: 17–30, 1994] and may in return benefit from amphibian nitrogenous waste. But identification of algal cells within the amphibian’s tissues was unexpected. This ‘association’ – it is too early to say what sort of symbiosis it might be or if the salamander obtains food from the alga, but which is viewed as a unique relationship between a vertebrate and a eukaryotic alga – poses many questions relating to cell–cell recognition and possible exchange of metabolites or DNA. And, like other symbioses, this new one raises further questions concerning the role(s) of ‘helping hands’ in the course of evolution.