LabLit.com

Please visit our new site!

Interview

The natural history of a plant scientist

8 July 2006

www.lablit.com/article/131

The beginning of the affair: a young Harberd with a dwarf mutant maize plant 20 years ago in Berkeley, where his whole growth project started

I wanted to write something that portrayed science from within the context of a mind that is thinking creatively about science, rather than simply portraying the science as a separate entity

Dr. Nicholas Harberd, a renowned plant biologist, runs a laboratory at the UK's prestigious John Innes Center and also holds an Honorary Professorship in Biological Sciences at the University of East Anglia. His book Seed to Seed: The Secret Life of Plants was recently published by Bloomsbury and has been hailed as a literary as well as scientific achievement. LabLit.com caught up with Harberd to find out more.

Have you always been interested in plants?

I think it was in some sense inevitable that I should have an interest in plants, because of family history. My grandmother (my father's mother) was an energetic gardener and her enthusiasm led, at least in part, to my father in turn studying plants, doing a degree in Agricultural Botany in Aberystwyth and continuing in academic plant science as Lecturer and then Reader in Agricultural Botany at the University in Leeds, where I was brought up. So plants were part of the home atmosphere throughout my childhood.

What is your earliest memory in which a plant played an important role?

There are many such memories, some of them described in the book. Again, some of them involve my father, collecting wild flowers and grasses for pressing for example. And the question is a good one because I certainly find as I get older that such memories have great influence over my scientific thought. It's hard to be sure what the very earliest of these memories is, but here is one from when I was five or six years old, as described in the book:

It was April, perhaps May. A sparse classroom at my infant school. High ceiling, bare floorboards. A beam of sunlight filtered through eddying specks of dust, falling on some twigs of horse chestnut standing in an old jam-jar of water. The day before, they'd carried large, fat buds which I'd squeezed, feeling the plump firmness and the sticking tug of the gum on my fingers. Now, as I ran into the room, I instantly saw that the buds had been replaced by fragile lime-green leaves, leaves that were expanding into the warmth and the sunlight. I stopped running, stood still, and took the whole thing in, letting my gaze travel up from the scarred, pitted grey wood, past the splayed and shrivelling scales of the bud-cases. To the apex of the thing, an ultimate chorus of green furry arms and the outstretched hands of leaves. The hands, tiny miniatures of their final form, laced with veins, reaching to the sun with expanding palms and fingers. Shining with the light of miracle.

Was there a point when you made a conscious decision to follow a scientific path or has that desire always been there?

Whilst I was at school I had many interests: music, literature as well as science. And I don't really think there was any particular moment when I decided to take the scientific path. I think that overall I'd always had this sense that I loved life and that the scientific understanding of it as revealed by biology was what most concerned me. But I don't want to give the impression that the scientific path was simple or unquestioned. Certainly there were moments when I wondered if my mind were more suited to an artistic path. And for a while, even once I was well along the scientific path, it was not clear that I was going to be a plant biologist. I actually specialised in genetics in the final year of my degree course at Cambridge and thought seriously about doing my PhD research on the fruit-fly Drosophila melanogaster rather than on plants.

You study Arabidopsis thaliana, the 'thale cress', which has been called the 'fruit fly of the plant world' because it is favored by geneticists. Why did this plant of all plants become a model organism?

Well, I think that there can be no question that the science of plant biology has advanced hugely over the last twenty years or so because of the adoption of Arabidopsis as a model organism. To put it simply (and this is something that I describe in the book), Arabidopsis has both 'whole-plant' and molecular characteristics that make it particularly suited to being a model organism. The 'whole-plant' characteristics are that it is relatively small (so the thousands of plants needed for doing genetics take up little growing space), has a short generation time (helps with cranking through the generations in genetics experiments), and is genetically diploid (many plants are polyploid, and polyploidy complicates 'Mendelian' genetics and the search for new recessive mutations). The most important molecular characteristic is that the Arabidopsis genome is relatively small compared to that of most plants. This facilitated the sequencing of the entire Arabidopsis genome (the first plant genome to be sequenced: a major scientific feat that was completed around 1999-2000). That genome sequence is now a hugely important foundation to many of the experiments that we do today.

And it is important to realise that this 'model' plant is genuinely a model. Many of the things that we are discovering about Arabidopsis are things that are true (or at least form the basis for an understanding) of other plants: the crop plants upon which we depend for our food, and the entire diversity of plants that are a fundamental part of our biosphere.

What is the basic thrust of your research?

I'm interested in growth, and in particular in how the growth of plants is regulated, both by factors internal to the plant and by factors in the environment within which the plant grows. My laboratory developed the idea that plant growth is controlled via a mechanism which we call 'relief of restraint'. The idea is that a family of proteins called the DELLAs restrain growth, whilst a plant growth hormone called gibberellin (GA) promotes growth ('relieves restraint') by causing the destruction of the DELLAs. Lately we've become particularly interested in the way in which the external world (the environment) controls the growth of plants by influencing the balance of this internal 'relief of restraint' mechanism, by modulating the relationship between GA and DELLAs. Our discovery of this interaction between the external world and the internal workings of the plant is one of the major scientific themes of the book.

Cover image courtesy of Bloomsbury.

Which science writer(s) or natural historian(s) have inspired and informed your own style?

I had been aware for a long time of the desire to write about science and about what it is like being a scientist in a way that is accessible to non-scientists. But I couldn't see a way to do it. On one level the book charts my stumblings towards a way of writing. I somehow realised that I need to relate my work to the growth of plants in the 'real' world and hence started going out into the wilds of Norfolk. At the same time I found myself re-reading Gilbert White's Natural History of Selbourne and beginning to use it as a model for writing something that was both accessible in a general sense and that also possessed scientific validity (in that there are some real scientific discoveries described in that book). I think that echoes of White's book remain in my own: a preoccupation with the seasons, climate etc. But I also became aware that I wanted more of a sense of the passage of time than there is in that book and so moved on to reading and absorbing a series of diaries/journal/notebooks: Dorothy Wordsworth, Coleridge, and Kilvert all had their influences on what I was writing, and in particular I found that the diaries of Virginia Woolf really helped me to evolve a language of observation that seemed to work within the context of what was then becoming my own book.

I also knew that I wanted to write something that is I think rather different to the way in which many books about science are written. I wanted to write something that portrayed science from within the context of a mind that is thinking creatively about science, rather than simply portraying the science as a separate entity. This 'mental self-portrait' is, I hope, a way to make non-scientists see science as an essentially human activity, done with passion, rather than as the unemotional and dispassionate activity that it is often regarded as.

Do you think the style of the book might inspire people to think differently about what a 'typical' scientist is?

Yes, or at least I very much hope so. We live in a civilisation that is sustained, at every level, by science and by the technology that derives from it. The future of that civilisation depends on our doing science/technology in the right way. Yet science, scientific thought, and the way that science works are all things that people in general have little understanding of. I think that it is possible that this lack of understanding exists (at least in part) because the way in which scientists go about the business of doing science is not generally appreciated. In painting an admittedly personal (and therefore perhaps somewhat idiosyncratic) picture of a scientist at work, I hope that I have helped people to think about what scientists actually are, and about what it means to be a scientist in the world today.

In the book, you follow a single Arabidopsis plant out in the wild through its entire life cycle over the year 2004. How did you choose your particular pet plant?

In the book I write of finally finding (after much searching) the 'pet' plant in the churchyard of St. Mary's, Surlingham – the idea of looking in a churchyard was sparked off by seeing a photograph in another book:

I rested for a while in the sunlit shelter of the flint wall that marks the boundary between graveyard and road. Then, walking along a line of graves to the north of the church, I suddenly felt the excitement of anticipation. Amongst the gravel covering one of these graves, I could see small splashes of green.

I walked closer, squatted at the foot of the grave. There is a headstone in the form of an open book. A body-length strip of ground. A low surrounding wall of mottled cream marble, the stone oddly cracked near one corner and patched with brown, like tea splashed on paper. The gravel is thinly laid, revealing in places the dark, wet soil beneath it. A heterogeneous landscape of aridity and moistness. Scattered amongst the sparse chips of stone are diverse weeds: docks, dandelions, thistles and so on. And amongst these, some thale-cress: star-like rosettes of leaves studded in the gravel.

The search was over...

Did you ever despair that it wouldn't make it? Or are they indestructible?

Thale-cress plants are definitely not indestructible! I describe in the book how my chosen plant spent much of its life teetering on the edge, managing to keep going despite near-fatal attacks from slugs, rabbits etc. The possibility that it might not 'make it' was always there, and I consider my personal feelings about this at several points in the book.

Would you recommend that more lab-bound biologists step outside and take a closer look at the bigger picture?

I wouldn't presume to advise other scientists what would be the best thing for them. All I can say is that it worked for me. And it worked both ways, in the sense that the 'stepping outside' (both physically and mentally) that the book entailed fed back beneficially into the experimental work of my research group.

However, I do think that we as scientists need to be aware of the tendency of scientific thought to be channeled or boxed off into our own particular specialisations. There is of course strength in this way of thinking, which is why we do it and why science has been so successful as a means to understanding the world. But I'm increasingly coming to the view that we need to balance this tendency with more open (or broader) ways of thinking if we are to really to gain a better picture of the world and the way that it works, and this developing view is one of the preoccupations of the closing sections of the book.

Any plans to write more books?

Well I have a few ideas bubbling away. Whether or not they'll come to anything meaningful remains to be seen!

Related links

You can order Seed to Seed here.