The humble spud

Humble? Boiled, mashed, fried, roast, chipped or prepared in many other ways, the potato is surely the King of Vegetables. And for 20 years in the 1970s and 80s, potatoes were the focus of my own research.

The potato (Solanum tuberosum) has something scientifically for everyone: the taxonomist or someone interested in crop diversity, geneticist or molecular biologist, breeder, agronomist, plant pathologist or entomologist, seed production specialist, biotechnologist, or social scientist. So many challenges – so many opportunities, especially since many potatoes are polyploids; that is, they have multiple sets of chromosomes, from 2x=24 to 6x=72.

MTJ collecting cultivated potatoes in 1974Much of my own work – both in the Andes of Peru in the early 70s and once I was back in Birmingham during the 80s – focused on potato genetic resources, understanding the evolutionary dynamics of speciation, and the distribution and breeding value of wild potatoes.

If you’re interested in species diversity, then the potato is the crop for you. In South America there are many indigenous varieties integral to local farming systems at high altitude. Grown alongside other crops such as oca (Oxalis tuberosa) and other Andean tubers of limited distribution, quinoa, and introduced crops such as barley and faba bean (that must have been brought to South America by the Spanish in the 16th century and afterwards). In a recent series on BBC TV (The Inca – Masters of the Cloud), archaeologist and South American expert Dr Jago Cooper repeatedly talked about the wonders of Incan agriculture as one of the foundations of that society yet, disappointingly chose not to illustrate anything of indigenous agriculture today. Farmers still grow potatoes and other crops on the exactly the same terraces that the Incas constructed hundreds of years ago (see my post about Cuyo Cuyo, for example). The continued cultivation of native potato varieties today is a living link with the Incas.

Native varieties of potato from Peru

Native cultivated potatoes are found throughout the Andes from Colombia and Venezuela in the north, south through Ecuador, Peru, Bolivia and Chile, and into northern Argentina. One of the main centres of diversity lies in the region of Lake Titicaca that straddles the border between Peru and Bolivia.

Another important centre of diversity is in the island of Chiloé , southeast of Puerto Montt, a well-known potato growing region of Chile.

The wild tuber-bearing Solanums have a much wider distribution, from the USA south through Mexico and Central America, and widely in South America. And from the coast of Peru to over 4000 m in the high Andes. They certainly have a wide ecological range. But how many wild species are there? Well, it depends who you follow, taxonomy-wise.

SM Bukasob

SM Bukasov

Some of the earliest studies (in the 1930s) were made by Russian potato experts SM Bukasov and SV Juzepczuk, contemporaries of the great geneticist and plant breeder, Nikolai I Vavilov.

In 1938, a young Cambridge graduate, Jack Hawkes (on the left below), visited the Soviet Union to meet with Bukasov (and Vavilov) as he would soon be joining a year-long expedition to the Americas to collect wild and cultivated potatoes. His PhD thesis (under the supervision of Sir Redcliffe Salaman) was one of the first taxonomies of wild potatoes. By 1963, Hawkes had published a second edition of A Revision of the Tuber-Bearing Solanums. By 1990 [1] the number of wild species that he recognized had increased to 228 and seven cultivated ones. Hawkes (and his Danish colleague Peter Hjerting) focused much of their effort on the wild potatoes of the southern cone countries (Argentina, Brazil, Paraguay and Uruguay) [2] and Bolivia [3]. Working at the National Agrarian University and the International Potato Center (CIP) in La Molina, Lima, Peru, potato breeder and taxonomist Carlos Ochoa (on the right below) spent several decades exploring the Andes of his native country, and discovered many new species. But he also produced monographs on the potatoes of Bolivia [4] and Peru [5].

Both Hawkes and Ochoa – rivals to some extent – primarily used plant morphology to differentiate the species they described or recognized, but also using the tools of biosystematics (crossing experiments) and a detailed knowledge of species distributions and ecology.

MTJ and JGH collecting wild potatoes

March 1975, somewhere above Canta in Lima Province. Probably a small population of Solanum multidissectum = S. candolleanum (that now includes S. bukasovii)

I made only one short collecting trip with Jack Hawkes, in March 1975 just before I returned to Birmingham to defend my PhD thesis. Travelling in the Andes between Cerro de Paso, Huanuco and Lima, at one point he asked me to stop our vehicle. “There are wild potatoes near here,” he told me. “To be specific, I think we’ll find Solanum bukasovii”. And within minutes, he had. That’s because Jack had a real feel for the ecology of wild potatoes; he could almost smell them out. I’m sure Carlos Ochoa was just the same, if not more so.


David Spooner

The potato taxonomist’s mantle was taken up in the early 1990s by USDA Agricultural Research Service professor David Spooner at the University of Wisconsin. Over two decades, and many field expeditions, he has published an impressive number of papers on potato biology. More importantly, he added molecular analyses to arrive at a comprehensive revision and understanding of the diversity of the tuber-bearing Solanums. In fact, in December 2014, Spooner and his co-authors published one of the most important papers on the biodiversity of wild and cultivated potatoes, recognizing just 107 wild and four cultivated species [6]. For anyone interested in crop evolution and systematics, and potatoes in particular, I thoroughly recommend you take the time to look at their paper (available as a PDF file).


[1] Hawkes, JG. 1990. The Potato – Evolution, Biodiversity and Genetic Resources. Belhaven Press, London.
[2] Hawkes, JG & JP Hjerting. 1969. The Potatoes of Argentina, Brazil, Paraguay, and Uruguay – A Biosystematic Study. Annals of Botany Memoirs No. 3, Clarendon Press, Oxford.
[3] Hawkes, JG & JP Hjerting. 1989. The Potatoes of Bolivia – Their Breeding Value and Evolutionary Relationships. Clarendon Press, Oxford.
[4] Ochoa, CM. 1990. The Potatoes of South America: Bolivia. Cambridge University Press.
[5] Ochoa, CM. 2004. The Potatoes of South America: Peru. Part 1. The Wild Species. International Potato Center, Lima, Peru.
[6] Spooner, DM, M Ghislain, R Simon, SH Jansky & T Gavrilenko. 2014. Systematics, diversity, genetics, and evolution of wild and cultivated potatoes. Bot. Rev. 80:283–383
DOI 10.1007/s12229-014-9146-y.


First impressions: two weeks in 1967

It was the first week of October, or thereabouts. 1967. I was headed to Southampton to begin a three-year undergraduate course in botany and geography at the city’s university.

Like all students in the UK, I’d applied for admission to six courses at different universities: King’s College, London (geography); Aberystwyth (zoology and geography); Southampton (botany and geography); York (biology); Queen Mary College (combined sciences); and Newcastle (botany and geography). I don’t really remember my priority list, but I do know that King’s was my first choice and Southampton was my third. I had interviews at King’s, Southampton, Queen Mary, and York; I never heard from the other two before I made my choice. The interview at York was a disaster. I was asked to describe Krebs Cycle, not something with which I was at all au fait. In fact, at a later date – at Birmingham – I came across something that an obviously bored student had written on a bench in one of the lecture rooms in the School of Biological Sciences: ‘I wouldn’t know Krebs Cycle if it ran me over‘. I couldn’t have agreed more!

Because I’d been off school with flu, I wasn’t able to make interviews at several universities on the dates requested around February or so in 1967, so had to try and reschedule these. My dad and I drove to the various campuses, and in fact ended up visiting York, King’s, and Southampton in the same week! The King’s interview went quite well, and I was offered a place. I can’t remember now who interviewed me, only that he was a Professor of Geography and had taught my elder brother Ed (1964-1967, in the Joint School of Geography between the London School of Economics and King’s).

Joyce Lambert in 1964

The day I visited Southampton was a bright sunny day, and even warm for that time of the year. In those days, the Department of Geography was housed in the Hartley Building (which also housed the library and various administrative departments), and I had a 1 hour interview with Dr Joyce Lambert* from the Department of Botany and Dr Brian Birch from Geography. The interview must have gone well because a few weeks later I received a conditional offer in the post. My place at Southampton was guaranteed if I received the necessary exam grades.

I accepted that offer. In fact, almost as soon as I walked through the front door of the Hartley Building I knew I would accept an offer from Southampton. I just had this immediate feeling of well-being. And my instinct didn’t let me down. I had three wonderful undergraduate years there.

In the late 60s, Southampton was still quite a small university, with only about 4500 undergraduates. After all it had received its own charter only in 1952; prior to that its degrees had been awarded by the University of London. Today there are more than 16,000, and the expansion has been phenomenal over the past 45 years since I graduated. A medical school opened not long after I graduated, and the botany department merged with other life sciences and moved to another campus location about a mile away. The Centre for Biological Sciences is now back on the main campus.At the end of my first year, in 1968 or early 1969, the geography department (now geography and environment) moved to a new building (part of that late 60s expansion that benefitted Southampton), but is now housed in the Shackleton Building, actually the old botany building 44 where I studied for three years.

However, to return to that first week in 1967. I may have difficulties these days remembering what I did last week, but my early memories of Southampton are crystal clear.

The tower block of South Stoneham House. I had a room on the west-facing sixth floor (shown here from Woodmill Lane) in my first year, and a south-facing room on the 13th floor in my second year. This block, constructed in the 60s, has been decommissioned because of an asbestos problem.

I was lucky to secure a place in one of the halls of residence, South Stoneham House, and had sent a trunk with clothes and other belongings on ahead of my arrival. The Students Union had organised a special train from London Waterloo to carry new undergraduates – or Freshers – to Southampton, and arrange transport at the other end to everyone’s accommodation. I stopped with my brother Ed for a couple of nights in London. He had just started his first job after graduating from LSE that summer. I bought his bicycle and on the day of my train to Southampton, I hopped on that bike and rode it through the rush hour traffic from his flat in Kilburn across the Thames to Waterloo. I left it at the station and returned to the flat to collect my suitcase. At Waterloo I retrieved my bike from the Left Luggage office, deposited it on the train and then searched for a seat. In those days, railway carriages were generally not open plan as they are today, but had a corridor down one side and compartments with seat for eight passengers. I remained close friends with three of the other seven in that compartment for the rest of my time at Southampton, and have kept in touch with one, Neil Freeman, ever since. We were even assigned rooms on the same floor at South Stoneham House.

Neil studied law, and in fact my close circle of friends was generally outside either botany or geography. Another law student who became a good friend was Malcolm Forster. I did lose contact with him but did come across his name a couple of years ago and briefly made contact then. Recently, however, he came across one of my blog posts and left a comment.

They often say that first impressions last longest. Well, these two in February and October 1967 certainly remained with me. Choosing Southampton over other universities was one of the best decisions I’ve ever made. Three great years, and good friendships. What more can you ask for?

* Who received the nickname ‘Blossom’ from several generations of botany students.