Plant Watch: Portland Spurge

Here's Euphorbia portlandica, Portland Spurge. It's a relatively common, coastal plant found on sand dunes around the country, while being less common on the west coast.

Tending to grow low across a dunes, the red stems are a diagnostic feature.

It's a species in the genus Euphorbia, which contains 1603 species and  belongs to the Euphorbiaceae family. The plants bloom from June to August (this photo was taken in late August at Cullenstown, Co. Wexford).

The flowers are aranged as cymes - a more or less flat-topped flower-cluster. Don't confuse it with sea spurge (Euphorbia paralias) which is taller, with larger, less yellow flowers. The bracts of Portland Spurge (those modified leaves associated with the flower) are "ace of spades" shape with a tiny point at the end.

In praise of the potato

Image: Courtesy of the Southern Star. Details below.

I was delighted to take a trip to Liss Ard Estate, just outside Skibbereen, West Cork, yesterday to speak about the potato plant at a seminar organised by A Taste of West Cork Food Festival.

The panel of speakers for the event included Regina Sexton of UCC, Madeline McKeever of Brown Envelope Seeds and Éanna ní Lamhna, author and RTE radio contributor.

Éanna opened the evening with an informative and exciting summary of the history of the potato and its arrival in Ireland. This was followed by Regina Sexton's presentation on the potato as a food item amongst both the rich and poor in Ireland.

Madeline McKeever spoke of her experience as an organic grower based in West Cork and about the interesting work done by the Sarvari Research Trust to breed blight-resistant potato varieties.

My own talk centered on the historic and present-day impact of late blight on the potato crop and the recent advances in the science of the potato.

I pointed out that an “arms race” now exists between the late blight-causing pathogen Phytophthora infestans and those who would seek to control it. The pathogen’s genome, its genetic blueprint, was sequenced in 2011 and this shows us that it is an incredibly flexible and rapidly-adapting organism. As we develop new fungicides or resistant potato varieties to control late blight, it is just a matter of time before Phytophthora infestans evolves to overcome these barriers.

We have a number of options for the future including the development on new, blight-resistant potato varieties. These varieties can be developed via conventional breeding methods: for example, Teagasc developed the highly successful Rooster variety via its breeding programme and that potato now accounts for about 50% of all potatoes grown in Ireland. Unfortunately it’s not fully resistant to late blight.

Resistant varieties do exist and they are often employed in an organic setting: sarpo mira, blue Danube, etc. However, consumers are reluctant to change from the traditional varieties.

As expected the issue of the recent planting of GM blight-resistant potato plants in Ireland was raised by a number of audience members. I expressed my view that a small-scale, well-designed, open and honest experiment such as this, conducted by a well-respected public body such as Teagasc is to be welcomed.

Opponents of GM often call for more information and more testing to be done on GM plants. This is exactly what the Teagasc experiment is designed to give us.

We must use all the tools at our disposal: organic, conventional and GM to control late blight and protect the potato, a plant which has huge social, historical and economic importance for this country.

The event concluded with a sampling of some delicious potato-based recipes (the lemon potato cake was particularly to my liking) as well as some gripping drama provided by the Skibbereen Theatre Society. All in all, a wonderful celebration of the potato plant.

A Taste of West Cork Food Festival continues this week. More details of other events.

Image: Speakers and organisers of the "Humble Spud" event at Liss Ard. Image courtesy of the Southern Star. Seated (l-r) Madeline McKeever, Regina Sexton, Éanna ní Lamhna, Eoin Lettice. Standing (l-r) Michael Hurley (Chair) and Kay Quinn (Organising Committee) 

Read the Irish Examiner's coverage of the event here.

The Story of You

Here's a nice new animation from Nature and narrated by the excellent Tim Minchin looking at the history of genetics, the human genome and the ENCODE (Encyclopedia of DNA Elements) project - a project designed to identify and characterise 'functional elements' in the human genome. It's obviously very much oversimplified but is clever and charming nonetheless.

I'm A Scientist comes to Ireland

The wonderful I'm a Scientist, get me out of here (IAS) will take place, for the first time, in Ireland this Autumn.

As I posted back in July, IAS will run in conjunction with Science Week and will consist of five zones where school-goers can ask scientists anything they like!

It's been described as an 'X-Factor for scientists' and allows the sort of relaxed interaction between scientists and potential scientists that provides for a wonderful learning experience for everyone who takes part.

I took part in IAS in the Spring of 2011 when it was a predominantly UK event (and got the mug to prove it!). If you're a scientist and think you might like to participate or a teacher who might like to get your students involved, the following posts I wrote on the subject might be a useful read:

Here's a 'before' post talking about what I wanted to achieve from participating.

Here's a post detailing how it all worked and the types of questions I was asked.

And finally, a post I wrote after I was booted out. A reflection on the whole event and it's value to student and scientists alike.

I really enjoyed taking part in IAS and it gave me a view of science outreach that I hadn't had before. If you're interested in taking part, I can highly recommend it. Find out more information on the IAS Ireland website.

Why organic must turn to science to survive

According to a couple of recent news stories, organic food is no better for you or the environment than conventionally farmed food. While growers and consumers would do well to take a closer look at the findings before making up their minds, the organic sector needs to turn to science if it is to remain relevant.

The big organic story of the week is a Stanford University meta-analysis which has variously been reported as showing that "Organic food no healthier" (Irish Times), "Why organic food may not be healthier for you" (NPR), and "Organic food is 'not healthier'" (Telegraph).

According to the study published in Annals of Internal Medicine, there is little evidence from 237 existing studies that suggest organic foods are more nutritious than conventional alternatives. The authors do acknowledge that consumption of organic foods "can reduce the risk of pesticide exposure". Clearly the healthiness of a foodstuff is more than just its nutritional value, so the reduced pesticide use on organic foodstuffs is worth noting.

“Some believe that organic food is always healthier and more nutritious,” said Crystal Smith-Spangler, co-author of the report. “We were a little surprised that we didn’t find that.” Perhaps they shouldn't have been given that a 2009 analysis of 50-years of research showed similar results.

Some commentators have mentioned that they don't purchase organic because it is better for them, they shop organic because it is good for the environment. It seems, however, that this claim may not live up to further scrutiny.

The second, and less widely reported organic story of the week is a study by Oxford University scientists which suggests that while organic farming is good for biodiversity, it does not necessarily have a lower impact on the environment than conventional food production.

The Oxford study, published in the Journal of Environmental Management, is a meta-analysis of 71 peer-reviewed studies conducted in Europe. The authors report that "whilst organic farming almost always supports more biodiversity and generally has a positive wider environmental impact per unit of land, it does not necessarily have a positive impact per unit of production."

The study showed that organic production generally needed less energy, but more land than the same amount of conventional produce. While biodiversity was 30% higher on organic farms, the production of organic milk, cereals and pork all generated more greenhouse gases than the conventional alternative.

"Many people think that organic farming has intrinsically lower environmental impacts than conventional farming but the published literature tells us this is not the case," said Dr Hanna Tuomisto, who led the research at Oxford University's Wildlife Conservation Research Unit (WildCRU). "Whilst some organic farming practices do have less environmental impact than conventional ones, the published evidence suggests that others are actually worse for some aspects of the environment. People need to realise that an "organic" label is not a straightforward guarantee of the most environmentally-friendly product".

an organic stamp should not be seen as the pinnacle of achievement in terms of sustainable food production What these two studies clearly show is that an organic stamp should not be seen as the pinnacle of achievement in terms of sustainable food production. On the other hand there are clearly some advantages of growing organically - increased biodiversity on farms and a decreased use and exposure to pesticides being just two highlighted in these studies. While these are positives, as conventional agriculture slowly moves away from the worst excesses of pesticide use, the importance of purely organic production may wane.

I've long argued for a third way - an agricultural system based on science where what works and is safe from all systems of agriculture can be used together to get the best results for growers, consumers and the environment.

If organic farming is to remain relevant in an era of growing food insecurity, it must be based on rigorous science and clear evidence. The organic sector must also begin to pick its battles. Organic is not the answer to all of the worlds problems. It does however have real contributions to make in terms of biodiversity and sustainable pest management.

Keeping the blooms alive

Ever the romantic, I bought my beloved a clump of dying plant tissue to put in a vase on the kitchen window. Of course I didn't put it quite like that when I brought them home but it's good to remember what you are buying when you pick up a bunch of flowers.

From the moment they are cut to the time when they end up in your wheelie bin, it's a battle against the inevitable to keep cut flowers alive and Spanish scientists have now shown that sugar and the plant hormones in the flowers themselves are key to keeping them looking their best long enough for your partner to forgive you for whatever you've done to offend.

A flower is a thing of beauty to be enjoyed but from a biological point of view it has a definitive job to do. The huge diversity in flower anatomy, colour and scent is largely related to pollination. Plants have evolved flowers to attract insects, birds and other animals to disperse pollen and fertilise the female reproductive organs.

From the colossal flowers of Rafflesia arnoldii – the largest flowers in the world at up to a metre in diameter, to the minute blooms of Wolffia species – the smallest in the world, the simple goal is the same.

Once fertilisation has occurred, the plant has no need for such gaudy displays and the petals are usually the first parts of the flower to show signs of decay once their job is done.

To counteract the short vase-life of flowers, a packet of 'flower food' is often included when you visit the florist. These products usually contain some sugar to act as an energy source; a compound to alter the acidity of the water to make it more suitable for the flowers; and a disinfectant to kill off any bacteria which could speed up decay in the vase.

Now researchers using lilies (Lilium longiflorum) have shown that adding sugar to the vase speeds up the opening of the flower and slows down its decay but doesn't affect the rate at which the petals drop off the flower - a sure sign your peace offering should have been binned already. The overall effect of these changes is a longer flowering window and a happy customer.

Laia Arrom and Sergi Munné-Bosch found that adding sucrose to the vase accelerated flower opening by 2.4 days and delayed its decay by 24 hours. Their work was published in the journal Plant Science earlier this year.

Further analysis of how the tissues of the flower use this sucrose showed that the petals and the male parts of the flower took up lots of the sugar and used it quickly. The female parts of the flower, on the other hand, took up sucrose and held on to it - a reserve, perhaps, for the female element's new role as a seed-bearer.

So, how did adding simple sugar to the distilled water in the vase increase the length of time the flowers kept their condition? Crucially, the addition of sucrose to the vase seemed to alter the balance of hormones in the flower tissues.

Hormones serve much the same function in plants as they do in animals - acting as chemical signals which can be transmitted over long distances.

It was already known that a particular group of plant hormones called cytokinins can delay the onset of floral decay and, sure enough, this recent study showed that a cytokinin called zeatin riboside was accumulated in the flowers, prolonging their vase-life.

Another plant hormone, abscicic acid, is known to speed-up the decay of petals and the researchers found that flowers treated with sucrose had 57% less absicsic acid compared to control flowers.

The cut flower industry is big business. A recent report (pdf) on the industry described it as being worth over US$100 billion a year worldwide. The UK share alone is worth around £2.2 billion - a 250% increase over the last twenty years. That's a lot of husbands doing a lot of apologising.

Whatever we're buying them for, consumers like flowers that stay alive long enough to enjoy them. This latest research suggests we're doing the right thing by adding sugar. The extra energy source is able to alter the balance of plant hormones enough to get an extra few days of enjoyment out of the blooms. If that doesn’t work, you may need to try a box of chocolates.

Blog Awards Ireland - Science Nominees

I'm delighted to say that Communicate Science has appeared on the long-list of blogs nominated been shortlisted for an Irish Blog Award.

The shortlist can be viewed here.

The blog was nominated in the Best Science/Education category alongside a host of other top Irish science blogs including: Science Calling, Scibernia, Deirdre Kelleghan and The Frog Blog.

The award ceremony will take place on 13th October. Thanks to everybody who reads, shares and reacts to the blog, I couldn't (and wouldn't want to) do it without you!

**post updated 11/09/12**