Taking in the central sierra . . .

September 1973. One of our first road trips in Peru, a circular route taking in Pisco on the coast south of Lima, before heading up into the Andes to Ayacucho, before heading north to Huancayo, and then back down to Lima. I’m sure the trip today is much easier than 43 or 44 years ago.

On the first day we drove south just as far as Pisco, spending one night there before attempting the next stage over the mountains to Ayacucho. Apart from the coastal Panamerican Highway and the road from Huancayo back to Lima, which were paved, the others were dirt roads in various states of repair. At the highest point on the road between Pisco and Ayacucho, we encountered one particularly stretch of muddy road that I thought we just might halt our trip. But with some expeditious maneuvering, I managed to extricate us from mud almost up to the axles.

The road up from Pisco.

If I remember correctly, the road dropping down to Ayacucho seemed to last forever, a long and relatively gentle decline. It was above Ayacucho where I took this photo, one of my favorites in all I took during our three years in Peru.

Staying at the turista hotel just off the main square, we spent a couple of nights in Ayacucho, and enjoyed its pleasant climate, lying as it does in a wide, fertile valley, just below 2800 m above sea level.

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North from Ayacucho the road crosses a wide, high altitude plain, dotted everywhere with cacti. Further north, it follows the steep-sided valley of the Mantaro River, and is carved into the side of the mountain. Maybe it has been widened today, but back in the day, it was so narrow that traffic flow was one-way only on alternate days. This had to be factored into our road trip planning of course.

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It was an easy day’s drive between Ayacucho and Huancayo, and we spent a couple of nights there. As the International Potato Center (CIP) had its highland experiment station close to Huancayo in the Mantaro Valley, and Steph and I would travel there almost every week during the potato growing season between November and May, we took the opportunity of passing through Huancayo to check a few work-related items before passing through on our way back down to Lima along that familiar road that crosses Ticlio at almost 5000m.

This trip must have lasted about seven days, maybe eight. With the others we made, as well as the various potato collecting trips that I made as part of my work, we were fortunate to explore many parts of this beautiful country.

Here is a list of those trips:


Breathing life into history

As regular readers of this blog will know, one of my hobbies is history (and archeology to some extent). I’ve often wondered whether I should have read history at university instead of botany. And, when I retired almost eight years ago, I did ponder taking a history degree course at the Open University. However, having decided that retirement meant I no longer had to meet deadlines any more, the allure of studying again soon faded.

Nevertheless, much of my reading focuses on history, and I’ve built up a sizeable library (mostly paperbacks) covering all periods and disciplines (social, economic, cultural, etc.). When we lived overseas in the Philippines I would take back half a suitcase of books after each annual home-leave in the UK. Near where my elder daughter lives in St Paul, Minnesota there is an excellent book store where I’ve been able to pick up a whole range of texts, many about the American Civil War, that I’ve never seen on sale over this side of the Atlantic. There are several university colleges near Half Price Books on Ford Parkway, where students divest themselves of course books each year—to my great advantage.

Here in the UK we are also fortunate that BBC2, BBC4 and Channel 4 regularly broadcast history programs of high quality, and others on archaeology, that provide interesting perspectives on how cultures and societies evolved. Steph and I have been enjoying many of these since we returned to the UK in 2010.

I guess my own fascination with history and archaeology on TV began with Sir Kenneth Clark’s Civilisation, a thirteen part documentary series, first broadcast on BBC2 in 1969 about the history of Western art, architecture and philosophy since the Dark Ages. It was apparently the first series commissioned specifically for colour television in the UK (by Sir David Attenborough, then Controller of BBC2). I didn’t actually see the series then; I was too busy being an undergraduate. We acquired the DVD in 2005.

Jacob Bronowski’s The Ascent of Man, broadcast in 1973 (and which we also viewed years later on DVD), was a highly-acclaimed personal view about the development of human society through its understanding of science.

Simon Schama’s A History of Britain (broadcast from September 2000, over 15 hour-long programs in three series until June 2002) was his personal view of different periods of British (actually, mainly English) history and its events. Once again, we caught up on DVD.

And during this period of working overseas, we enjoyed (on DVD) an impressive list of programs by Michael Wood, in a broadcasting career that began in 1979. He has had several series since we returned to the UK.

David Starkey is a hardy perennial who focuses on the Tudors. Despite several controversies that have surrounded him, he still appears quite regularly.

There is quite a long list of presenters (see below) whose programs we have enjoyed since 2010, covering a wide range of topics and periods. Just this past few weeks we’ve enjoyed a three-part series by Helen Castor about England’s first queen, Jane (great granddaughter of Henry VII), whose reign lasted just nine days in July 1553.

Art historian Andrew Graham-Dixon is the ‘flavor of the month’ right now. A two part series, Rome Unpacked, co-presented with chef Giorgio Locatelli about the cultural history of Rome and its cuisine concluded last week. For some reason we didn’t watch the three series of Italy Unpacked broadcast between 2013 and 2015. He’s just started a four part series about the Royal Collection on BBC4, and next week he has a one-off program on BBC2 about the theft of two paintings by Van Gogh from a museum in Amsterdam in 2002. He’s certainly one of the most engaging presenters currently on TV.

But there are two presenters who are new to me with series showing right now on BBC2 and BBC4, respectively.

David Olusoga is a British Nigerian historian, writer and broadcaster who I’d never heard of until his four part series A House Through Time began three weeks ago. It tells the social history of Liverpool through the lives of families who occupied a single house, from when it was built about 200 years ago until the present day.

62 Falkner Street (at one time, number 58) is a four storey terraced house in what was once a fashionable neighborhood, in the Georgian Quarter east of the city center, but within easy striking distance of the docks that were the basis of the city’s prosperity for so many decades.

It has been painstakingly researched. There must be a large team of researchers behind the scenes digging into the census records and other documents published in Liverpool that have provided insights into the business and economic history of the city. It’s a very engaging way to tell the social history of this important port city in England’s northwest, that climbed to the pinnacle of economic prosperity in the 19th century, and fell to the depths of economic decline in the late 20th.

Combining the history of art and fashion, A Stitch in Time (a six part series on BBC4) is presented by TV newcomer Amber Butchart, who has published several books and appears regularly apparently on BBC radio.

Amber is certainly a breath of fresh air, with her flamboyant fashion style, bright red hair, and piercingly blue eyes. Her range of clothes certainly needs a personality like Amber’s to carry off successfully. Elegant!

Working with historical costumier Ninya Mikhaila and her team, Amber fuses biography, art, and the history of fashion, and explores the lives of historical figures through the clothes they wore.

In the first program, she looked at the fashion of Charles II’s restoration, and in the second the green gown worn by the lady in the 1434 Arnolfini portrait, painted by Jan van Eyck. The third program was unusual in that the portrait was of a working man, a hedge-cutter, wearing a hand-me-down leather coat.

In each program Amber talks about the social status and lives of the subjects that we can deduce from each painting, while Ninya and her team recreate a costume just from their view of the painting and their detailed understanding of how clothes were made in the past. The Arnolfini recreation was outstanding.

From the outset I wouldn’t have imagined that a series along these lines would grab my attention. I guess we watched the first episode because there was nothing else worth watching across the channels. But then we were hooked, and I hope that the BBC will commission Amber to undertake other projects in the future.


  • Dan Snow: a Modern History graduate from Oxford University, Snow has an impressive list of programs under his belt.
  • Mary Beard: Professor of Classics at Cambridge University, Beard has presented programs on Rome and Pompeii, among others. Very entertaining.
  • Niall Ferguson: Scottish-born Ferguson has affiliations with many academic institutions on both sides of the Atlantic and specializes in economic and financial history.
  • Simon Sebag-Montefiore: he has presented some excellent city histories, on Jerusalem, Rome, Byzantium, and Vienna.
  • Lucy Worsley: she is Joint Chief Curator of Historic Royal Palaces, and has been presenting since 2009, and has written a number of books. Renowned for her penchant for dressing up in her programs, I guess she is not everyone’s cup of tea. But we find her engaging.
  • Suzannah Lipscombe: is Reader in Early Modern History at the University of Roehampton, and has an impressive list of TV programs to her name.
  • Bettany Hughes: specializes in classical history, and has been broadcasting since the late 1990s.
  • Clare Jackson: is a senior tutor at Cambridge University and has a particular interest in 17th century English history.
  • Dan Jones: a writer and historian, his book on the Plantagenets was adapted for television in 2014 on Channel 5.
  • Sam Willis: is a military historian affiliated with the University of Plymouth.
  • Saul David: is Professor of Military History at the University of Buckingham.
  • Ruth Goodman: is a British freelance historian of the early modern period, specializing in offering advice to museums and heritage attractions.
  • Janina Ramirez: is an art and cultural historian, who works at Oxford University’s Department of Continuing Education.
  • Jago Cooper: archaeologist and the Curator of the Americas at the British Museum, and specializes in the history and pre-Columbian archaeology of South America. He has presented programs on the Incas and lost kingdoms of Central America (areas particularly close to my heart, having lived in Peru and Costa Rica for over eight years in the 1970s).
  • Neil Oliver: is a Scottish archaeologist who has presented programs on the Vikings and is a resident presenter on Coast.
  • Alice Roberts: is Professor of Public Engagement in Science at The University of Birmingham. A medical doctor and anatomist by training, Roberts front many programs bringing together expertise in archaeology and history, and appears frequently on the BBC.
  • Waldemar Januszczak: is an art critic and TV presenter and documentary producer, with many films to his credit since 1997.

Wishing I was in Cuzco . . .

The 10th World Potato Congress takes place in the southern Peruvian city of Cuzco at the end of May this year. I wish I was going.

It would be a great opportunity to renew my links with potato research, and revisiting one of Peru’s most iconic cities would be a joy.

I like this quotation from the Congress website: Potatoes are the foundation of Andean society. It shaped cultures and gave birth to empires. As the world population explodes and climate change places increased demands on the world’s farmers, this diverse and hearty tuber will play an instrumental role in feeding a hungry planet.

Cuzco lies at the heart of the Andean potato culture. The region around Cuzco, south to Lake Titicaca and into northern Bolivia is where most diversity in potatoes and their wild species relatives has been documented. When I worked for the International Potato Center (CIP) in Peru during the early 1970s I had several opportunities of looking for potatoes on the Peruvian side of the border, and made three (possibly four) visits to Cuzco. I see from a quick scrutiny of the street map of Cuzco on Google maps that the city has changed a great deal during the intervening years. That’s hardly surprising, including many fast food outlets dotted around the city. The golden M get everywhere! Also there are many more hotels (some of the highest luxury) in the central part of the city than I encountered 45 years ago.

At Machu Picchu in January 1973

I visited Cuzco for the first time within two weeks of arriving in Peru in January 1973. The participants of a potato germplasm workshop (that I described just a few days ago) spent a few days in Cuzco, and I had the opportunity of taking in some of the incredible sights that the area has to offer, such as Machu Picchu and the fortress of Sacsayhuamán on the hillside outside the city.

Steph and I were married in Lima in October 1973, but we delayed our honeymoon until December. And where could there be a more romantic destination than Cuzco, taking in a trip to Machu Picchu (where we stayed overnight at the turista hotel right beside the ruins), Sacsayhuamán, the Sacred Valley, and the Sunday market at Pisac.

In the early 70s, the Peruvian airline Faucett flew Boeing 727s into Cuzco. In January 1973 I’d only ever flown three times: in 1966 to the Outer Hebrides in Scotland on a BEA Viscount turboprop; from London to Istanbul on Turkish Airlines to attend a scientific meeting in Izmir; and the intercontinental flight from London to Lima with BOAC.

Flying into Cuzco was (is) quite an experience. There’s only one way in, and out! It is quite awesome (if not a little unnerving) dropping through the cloud cover, knowing that some of the highest mountains in the world are just below, then seeing the landscape open as you emerge from the clouds, banking hard to the left and follow the valley, landing at Cuzco from the east.

The city has now expanded eastwards beyond the airport, but in 1973 it was more or less at the city limits. The main part of the city lies at the western end of the runway, and hills rise quite steeply just beyond, thus the single direction for landing and the reverse for take-off. Maybe with new, and more highly powered aircraft, it’s now possible to take off to the west. Those attending the World Potato Congress should have a delightful trip from the coast. By the end of May the dry season should be well-established, and the skies clear.

So, what is so special about Cuzco? It’s a city steeped in history, with Spanish colonial buildings blending into, and even constructed on top of the Inca architecture. That architecture leaves one full of wonder, trying to imagine how the stones were brought to the various sites, and sculpted to fit so snugly. Perhaps the best example is the twelve-sided (or angled) stone in the street named Hatun Rumiyoc (a couple of blocks east of the Plaza de Armas). This is taken to an even greater level at Sacsayhuamán, with an enormous eleven-sided stone.

My first impressions of Cuzco were the orange-tiled roofs of most buildings in the city.

All streets eventually lead to the main square, the Plaza de Armas in the city center, dominated on its eastern side by the Cathedral Basilica of the Assumption of the Virgin, and on its southern side by the late 16th century Templo de la Compañía de Jesús (a Jesuit church).

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One of the finest examples of the Inca-Colonial mixed architecture is the Coricancha temple upon which was constructed the Convent of Santo Domingo. The Incan stonework is exquisite (although showing some earthquake damage), and inside 16th/17 century paintings have survived for centuries.

Another aspect of Cuzco’s architectural heritage that caught our attention were the balconies adorning many (if not most) buildings on every street, at least towards the city center.

In the early 1970s steam locomotives were still in operation around Cuzco and, being somewhat of a steam buff, I had to take the opportunity of wandering around the locomotive shed. During our trip to Machu Picchu, our tourist diesel-powered train actually crossed with another pulled by a steam locomotive.

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Outside the city, to the north lies the Inca fortress citadel of Sacsayhuamán, the park covering an area of more than 3000 hectares. Steph and I spent a morning exploring the fortress, viewing it from many different angles, and pondering just how a workforce (probably slave labour) came to construct this impressive site, with its huge stones so closely sculpted against each other that it’s impossible to insert the blade of a knife.

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Among the most commonly visited locations by many tourists is the small town of Pisac, some 35 km from northeast of Cuzco at the head of the Sacred Valley, where a vibrant market is held each Sunday. We took a taxi there, and joined quite a small group of other tourists to wander around, bargain for various items (including an alpaca skin rug that we still had until just a couple of years ago). This is not a tourist market, however—or at least it wasn’t in December 1973 when we visited. As you can see in the slideshow below, it was very much a place and occasion frequented by people coming from the surrounding communities to sell their produce, and meet up with family and friends. Whenever I look at these photographs I always feel quite sad, as it’s likely that many who appear have since passed away.

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It’s no wonder that Cuzco and surrounding areas have been afforded UNESCO World Heritage status (as so many other treasures in this wonderful country). So, as I think about the opportunities that potato scientists from all around the world will enjoy when they visit Cuzco at the end of May, I can’t help but feel a tinge of envy. However, they’d better take advantage of the odd cup of coca tea, or maté de coca, if offered. An infusion of coca leaves (yes, that coca!), it really does help mitigate the effects of high altitude and the onset of so-called ‘altitude sickness’.


How long is a piece of string?

Just three decades after Spanish conquistador Francisco Pizarro first encountered the potato in the high Andes of Peru in 1532, the potato was already being grown in the Canary Islands. And it found its way to mainland Europe via the Canaries shortly afterwards [1].

The first known published illustration of the potato in Gerard’s Herball of 1597.

The potato was described by English herbalist John Gerard in his Herball published in 1597. In a revised version, published in 1633 over 20 years after his death, there is another beautiful woodcut of the potato, referred to Battata Virginiana or Virginian potatoes.

Potatoes became an important crop by the late 18th century, and particularly the staple of Ireland’s impoverished citizens in the years leading up to the Irish Potato Famine of the mid-1840s.

Today, potatoes are one of the world’s most important crops, grown in every continent except Antarctica. Known scientifically as Solanum tuberosum, it was given this name by the famous Swedish naturalist, Carl Linnaeus in his 1753 magnum opus, Species Plantarum.

The potato and its wild relatives must be one of the most studied groups of crop plants. Not that I’m biased (having researched potatoes for more than 20 years).

Potato diversity and germplasm collections
Its clear that there is a wealth of information about the diversity within the section of the genus Solanum that encompasses the potato. They have been studied extensively from a taxonomic point of view, breeding efforts worldwide have incorporated genes from many wild species to enhance productivity, and important germplasm collections were set up decades ago to preserve this important diversity, to study it, and use it in potato breeding.

My former colleague (and fellow PhD student at Birmingham), Dr Zosimo Huaman, describes the management of CIP’s wild potato collection in Huancayo to members of the CGIAR’s Inter-Center Working Group on Genetic Resources who held their annual meeting at CIP in 1996.

Among the most important collections are held at:

The wild relatives of the potato have one of the broadest geographical and ecological ranges among species that have been domesticated for human consumption. While the various forms of cultivated potatoes were domesticated in the Andes of Peru and Bolivia, and on the coast of Chile, the wild species are found from the southwest USA (in the coniferous forests of Arizona, for instance) through Mexico and the countries of Central America to Panama, along the Andes south to Chile and northern Argentina, and south and east on to the plains of Argentina, Brazil, Paraguay and Uruguay. Wild species are found in the coastal desert of Peru, in the cloud forests of central America to almost 3000 m, at the highest altitudes of the Andes, well over 4000 m, and also growing in the highly humid transition zone on the eastern side of the Andes dropping down to the lowland forests (known as the ‘eyebrow of the mountain’ or ceja de la montaña).

Here is just a very small sample of the diversity—and beauty—of wild potato species (photos courtesy of my friends at the Commonwealth Potato Collection).

How many potato species are there?
Well, it depends, to some extent, on one’s perspectives as a taxonomist, use of different species concepts, and the methods used to study species diversity, and also on the work that earlier taxonomists published.

Essentially, there are three basic taxonomic approaches:

  • Morphology: often based on the study of dried herbarium specimens collected in the wild. In the case of potatoes, this has led to the description of a multiplicity of species, with almost every variant being described as a separate species. This reliance on plant morphology was the approach taken by the 19th and early 20th century botanists.
  • Biosystematics: takes an experimental view of species diversity, of breeding behaviour and relationships, and very much based on collections in the field and the study of ecology, and growing samples in a uniform environment such as the study one of my PhD students, Susan Juned, made of Solanum chacoense, a species from Argentina and Paraguay.
  • Molecular biology: methods have become available in the last couple of decades to analyse the most basic variation in DNA, and helped to refine further how potato taxonomists view the diversity within the tuber-bearing Solanums, and the relationships between species.

While these different approaches still do not provide a definitive answer to the question of how many species there are, we know that taxonomists have described and named more than 200 species. To some extent it’s like asking how long is a piece of string. And that helps me to provide an analogy.

Take a piece of string. If you were to view this string along its length that, to your vision would be fore-shortened, it would be very difficult to say with any degree of certainty just how long the string actually was. However, if you increase the angle at which you view the string, until you are looking at right angles, your ability to estimate its length also increases. At right angles you can see the whole length, and measure it accurately in many different ways.

Taxonomic study is a bit like looking at the string from different angles. Each taxonomist builds on earlier studies, and describing new species or subsuming previously described ones into another species (as merely variants). This is one of the challenges of studying wild potato species: they are highly variable and show considerable phenotypic (or morphological) plasticity. It’s not always possible to study large numbers of plants under uniform conditions to reduce the variation caused by differences in habitats.

The 2n=3x=36 chromosomes of a triploid potato, from a root-tip squash in two cells.

Furthermore potatoes have considerable chromosomal variation, with a base number of x=12, with diploids (2n=24) the most frequent, and mostly self-incompatible (i.e. they cannot self fertilise), infertile triploids (2n=36, including two cultivated species), tetraploids with 2n=48 (mostly self-fertile, and including the cultivated Solanum tuberosum of world-wide agriculture), some pentaploids (2n=60; including one cultivated form), and a few hexaploids with 2n=72. Wild potatoes are uncommonly promiscuous when grown together under experimental conditions, and will inter-cross readily (they are bee-pollinated), yet hybrids often do not survive beyond the second generation in the wild. Many species are separated by ecology, and generally do not come into contact with each other, thus maintaining their species identity.

Nevertheless, this is what makes the study of potatoes and wild species so very interesting, and that captured my interest directly for over two decades, and continues to do so, even though I moved on to the study of other crops like rice and grain legumes.

The potato taxonomists
Many botanists have taken an interest in wild potatoes. During the 19th century, the Swiss-French botanist Alphonse de Candolle (d. 1893) named a number of species, as did François Berthault (d. 1916). But the first decades of the 20th century leading up to the Second World War saw a lot of collecting and taxonomic description. In Germany, Friedrich August Georg Bitter, who specialised in the genus Solanum, described and named many species. However, it was the involvement of several Russian botanists and geneticists, under the leadership of Nicolai Vavilov, that saw an expansion in the collection of potatoes throughout the Americas, but a systematic evaluation of this germplasm leading to even more species being described.

SM Bukasov

Two names come to mind, in particular: SM Bukasov and VS Juzepczuk. They were active during the 1920s and 30s, taking part in several missions to South America, and developing further the concept of potato species. But much of their work was based on morphological comparison leading to the identification of even small variants as new species.

In August 1938, a young Cambridge graduate, Jack Hawkes, traveled to Leningrad in Russia to meet and discuss with Bukasov and Juzepczuk (and Vavilov himself) in preparation for the 1938-39 British Empire Potato Collecting Expedition to South America (which Jack has described in his 2004 memoir Hunting the Wild Potato in the South American Andes [2]).

A young Jack Hawkes (second from right) stands outside a church near Lake Titicaca in northern Bolivia, alongside expedition leader Edward Balls (second from the left).

Jack Hawkes

That collecting expedition, and the subsequent studies (which led to Hawkes being awarded his PhD from the University of Cambridge in 1941 for a thesis Cytogenetic studies on South American potatoes supervised by renowned potato scientist Sir Redcliffe N Salaman), was the launch pad, so to speak, of potato taxonomy research for the rest of the 20th century, in which Hawkes became one of the leading exponents.

After Cambridge, Hawkes spent some years in Colombia (where he no doubt continued his studies of wild potatoes) but it was on his return to the UK in 1952 when appointed to a lectureship in the Department of Botany at The University of Birmingham (where he was to remain until his retirement in 1982) that his potato studies flourished, leading him to publish in 1956 his first taxonomic revision of the tuber-bearing Solanums (with a second edition appearing in 1963).

In 1990, he published his final synopsis of the tuber-bearing Solanums [3]; that taxonomic treatment is the one followed by the curators of the Commonwealth Potato Collection.

Jack’s approach to potato taxonomy was based on a thorough study of morphology backed up by rigorous crossing experiments, and a cytogenetic and sometimes serological evaluation of species relationships.

I first met Jack in February 1970 when he interviewed me for a place on his newly-founded MSc course on plant genetic resources, joining the course later that same year. In September 1971 I became one of Jack’s PhD students, joining others who were looking at the origin and evolution of the cultivated species [4].

Donovan S CorrellIn these revisions he was also taking into account the work of US botanist, Donovan S Correll who published his own potato monograph in 1962 [5], as well as three important South American botanists with whom he would collaborate from time-to-time: Professor César Vargas from the National University of Cuzco; Professor Martín Cárdenas from Cochabamba in Bolivia; and Professor Carlos Ochoa, originally from Cuzco, who was a professor at the Universidad Nacional Agraria (UNA) in La Molina, Lima and, around 1975 or so, joined the International Potato Center across the street from the UNA.

L-R: Danish botanist J Peter Hjerting, Martin Cardenas, and Jack Hawkes in Cochabamba.

Vargas published a number of species descriptions in the 1950s, but made his most significant contribution in his two part monographs, Las Papas Sudperuanas published in 1949 and 1956. I met Vargas on a couple of occasions, first in January 1973 just after I’d joined CIP as Associate Taxonomist. And a second time in February 1974 when I was passing through Cuzco with Dr Peter Gibbs from the University of St Andrews in Scotland. Peter was making a study of incompatibility among different forms of the Andean tuber crop, oca (Oxalis tuberosa), and had joined me on an excursion to Cuyo-Cuyo in the Department of Puno. Vargas’s daughter Martha was studying for her MSc degree under Peter’s supervision at St Andrews.

With Prof Cesar Vargas at his home in Urubamba, near Cuzco

It was Carlos Ochoa, however, whose studies of potatoes and their relatives rivalled (and in some respects eclipsed) those of Jack Hawkes. They were quite intense taxonomic rivals, with a not-altogether harmonious relationship at times. Carlos certainly played his taxonomic cards very close to his chest.

Me consulting with Carlos Ochoa concerning the identity of some triploid potatoes, in one the screenhouses at the International Potato Center in 1974.

But the fact that he grew up in the Andes and had, from an early age, taken an interest in the diversity of this quintessential Andean crop and its wild relatives, led him to dedicate his life to uncovering the diversity of potatoes in his homeland. He was also a potato breeder and released some of the most important varieties in Peru, such as Renacimiento, Yungay, and Tomasa Condemayta.

In this video (in Spanish, and broadcast on Peruvian TV on his death in 2008) he talks about his early life in Cuzco, the pressures on him to study medicine or become a lawyer, and how he found his true vocation: the study of wild potatoes.

Setting potato taxonomy and germplasm exploration priorities at CIP
Forty-five years ago this week, CIP convened the first planning workshop on the exploration and taxonomy of potatoes [6], inviting a group of taxonomists and potato breeders to meet in Lima and mull over the ‘state of play’ taking into consideration what taxonomic research had already been accomplished, what was in the pipeline, and what CIP’s germplasm exploration policy (especially in Peru) should be. I attended that meeting (as an observer), having landed in Lima just a few days earlier.

On the taxonomic side were Jack Hawkes, Carlos Ochoa, and Donald Ugent who was a ethnobotany professor at Southern Illinois University in Carbondale. Richard Tarn, a potato breeder from Agriculture Canada at Fredericton, New Brinswick, had completed his PhD under Jack’s supervision at Birmingham. Frank Haynes, a professor of genetics and potato breeder at North Carolina State University (and long-time friend and colleague of CIP’s first Director General, Richard Sawyer) and Roger Rowe [7], then curator of the USDA’s potato collection at Sturgeon Bay (who would join CIP in July 1973 as the Head of Breeding and Genetics, and become my PhD co-supervisor) were the other participants.

Workshop participants looking at CIPs germplasm collection in the field at Huancayo (3000 m) in central Peru. L-R: David Baumann (CIP field manager), Frank Haynes, Jack Hawkes, Roger Rowe, and Don Ugent.

In 1969, Jack had published (with his Danish colleague Peter Hjerting [8]) a monograph of the potatoes of southern cone countries of South America [9], and by the time of the CIP 1973 workshop was well into research on the potatoes of Bolivia [10], leading publication of a monograph in 1989.

Peter Hjerting collecting Solanum chacoense in Bolivia in 1980. Standing next to him is Ing. Israel Aviles, a Bolivian member of the expedition. Their driver looks on.

What I’ve never been able to fathom after all these years is why Ochoa decided to write his own monograph of the Bolivian species rather than concentrating in the first instance on the Peruvian species. Nevertheless Ochoa did produce his own fine monograph in 1990 [11], beautifully illustrated with some fine watercolours by CIP plant pathologist Franz Frey. This was followed by an equally magnificent volume on the potatoes of Peru in 2004 [12], also illustrated by Frey.

Throughout his expeditions and research, Ochoa was supported by several assistants, the most notable being Ing. Alberto Salas. Now in his mid-70s, he has been collecting wild potatoes for five decades.

I knew Alberto when I first joined CIP in 1973, and it was a delight to meet him again (although he had retired) during my visit to CIP in July 2016.

Taking up the baton
With retirement, Hawkes and Ochoa passed the potato taxonomy baton to a new generation of researchers, principally David Spooner, a USDA scientist at the University of Wisconsin-Madison who made several collecting trips throughout the Americas.

David Spooner

David’s research took potato systematics to a new level, employing the developing molecular and genomic approaches, and use of different classes of markers to help him refine his understanding of the diversity of the tuber-bearing Solanums, building of course on the very solid Hawkes and Ochoa foundations.

Although no longer working on potatoes (his most recent focus on carrots supported the PhD thesis of Carlos Arbizu, Jr, the son of one of my PhD students at Birmingham in the 1980s), David’s scientific output on potatoes has been prodigious. With molecular insights supporting more traditional methods he has proposed a 50% reduction in the number of potato species from the more than 200 listed in Hawkes’s 1990 publication.

Is this the end of the potato taxonomy story? Probably for the time-being. It’s unlikely that anyone will pursue these studies to the same depth as Hawkes and Hjerting, Ochoa, or Spooner. Nevertheless, as the curators of the Commonwealth Potato Collection have done, most potato researchers will take a pragmatic approach and fix on a particular taxonomic treatment on which to base their management or use of germplasm. Taxonomy is one of those disciplines in which subjective interpretations (obviously based on empirical studies of diversity) can lead to contrary classifications. What is a distinct species to one taxonomist may be merely a variant to another. Undoubtedly these different taxonomic treatments of the tuber-bearing Solanums have permitted us to have a much better appreciation of just how long ‘the potato piece of string’ really is.


[1] Hawkes, JG & J Francisco-Ortega, 1993. The early history of the potato in Europe. Euphytica 70, 1-7.

[2] Hawkes, JG, 2004. Hunting the Wild Potato in the South American Andes – Memories of the British Empire Potato Collectiing Expedition to South America 1938-1939. Wageningen, the Netherlands. ISBN: 90-901802-4.

[3] Hawkes, JG, 1990. The Potato – Evolution, Biodiversity and Genetic Resources. Belhaven Press, London.

[4] Since I was working on the origin and evolution of a cultivated species of potato for my PhD, I made only one short collecting trip for wild species with Jack in early 1975, to the Departments of Huanuco, Cerro de Pasco, and Lima. On his trips to Peru between 1973 and 1975 he would join me in the field to look at the germplasm I was studying and give me the benefit of his potato wisdom.

[5] Correll, DS, 1962. The Potato and its Wild Relatives. Contributions from the Texas Research Fiundation 4, pp. 606. Texas Research Foundation, Renner, Texas.

[6] International Potato Center, 1973. Report of the Workshop on Germplasm Exploration and Taxonomy of Potatoes. Lima, Peru. 35 pp.

[7] I’ve kept in touch with Roger and his wife Norma all these years. After I left CIP in 1981, Roger moved to East Africa to work with the animal diseases center that became ILRI after its merger with another CGIAR livestock center in Ethiopia. He was DDG-Research at CIMMYT in Mexico in the late 1980s and early 1990s. While I was at IRRI, he was based in Cairo working for the CGIAR center that became WorldFish (with its headquarters in Penang, Malaysia). Before it moved to Malaysia, ICLARM as it then was had its offices in Manila, and we would see Roger in the Philippines from time-to-time. It was great to meet up with Roger and Norma again in July 2016 when I was in Lima for the genebank review that I led.

[8] From what I can determine through a Google search, as of January 2018, Peter celebrated his 100th birthday in 2017. He has a Mexican tetraploid (2n=4x=48) species named after him, Solanum hjertingii. When I was at Birmingham in the 1980s I had two PhD students, Lynne Woodwards and Ian Gubb who studied this species because its tubers lack so-called enzymatic blackening, a trait that could be very useful in potato breeding.

[9] 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.

[10] Hawkes, JG & JP Hjerting, 1989. The Potatoes of Bolivia – Their Breeding Value and Evolutionary Relationships. Clarendon Press, Oxford.

[11] Ochoa, CM, 1990. The Potatoes of South America: Bolivia. Cambridge University Press, Cambridge.

[12] Ochoa, CM, 2004. The Potatoes of South America: Peru. International Potato Center, Lima, Peru.

Brexit means Brexit. What an almighty cock-up!

Forty-five years ago today, 1 January 1973, the United Kingdom (along with Denmark and Ireland) became a member of the European Economic Community (EEC), now the European Union (EU). Now we are on the verge of leaving the EU. March 2019 is not so far away.

Brexit is and, I believe, will become a social, political, and economic catastrophe for this country. I am firm Remainer, yet a member of that demographic who apparently swung the referendum vote in favour of Leave (I turn 70 in November this year). I refuse to be labelled a ‘Remoaner’.

What beggars belief is that the government apparently had no end-plan developed when Article 50 was triggered earlier in 2016 (and only just beginning to discuss this!), nor had they carried out comprehensive risk analyses or impact studies, never mind what Brexit Secretary David Davis has or has not said. His vagueness and the way he has approached the Brexit negotiations seemingly as a game with limited or no consequences is an insult to the nation.

What I still cannot fathom—and the blame must be placed at the door of former Prime Minister David Cameron—is why the referendum bar (which was ‘advisory’) was never set higher. By this I mean that there should there have been an absolute majority of the electorate required in favour of leaving the EU. As it is, only 37% of the electorate (almost 52% of those who voted) are forcing us out of the EU with all the consequences for our economy, for trade, security, travel, education, science, health, human rights. Every part of the fabric of the nation will be affected in one way or another. It’s also astonishing to me that parts of the UK that have benefited especially from EU membership (in terms of regional grants and the like) voted to leave, or that constituencies like the fishermen believe that things will improve for them post-Brexit.

I’m sick to death of hearing Brexit means Brexit, the will of the British people, the best deal possible, or taking back control. Well, Theresa, David, Boris Johnson and all you other second class politicians (or failed ones like Ian Duncan-Smith and Chris Grayling, to mention but two among the many, especially on the Conservative benches), I’m afraid the EU holds all the cards in these negotiations. Our status as a small island of diminishing consequence off the coast of mainland Europe will be confirmed.

Our accession to the EEC came a decade after the President of France, Charles de Gaulle famously failed to back the UK’s application to become a member stating that the British government lacks commitment to European integration. In November 1967, he vetoed the UK’s application a second time.

In the light of what has happened ever since, including a confirmatory membership referendum in 1975 under the Labour government headed by Harold Wilson, and subsequent constant carping from the sidelines by the British government under Margaret Thatcher, you have to admit that de Gaulle’s perspective was somewhat prescient.

From my own perspective, I was proud that Prime Minister Edward Heath eventually prevailed and signed the terms of accession to the EEC in December 1972.

I believe that membership has brought a level of stability and economic prosperity to the UK that we could not have achieved on our own. The EU represents a market for 50% or more of our international trade. And now we are about to throw that away and jeopardise our future. Talk about baby and the bath water.

More than 50% of the UK population (based on 2011 census demographic data) were born at or after the UK joined the EEC. That goes up to around 75% if you take into account those who were teenagers or so on accession. The UK inside the EEC/EU is all they have ever known.

I’m a passionate supporter of continued membership of the EU. Well, perhaps passionate is a little strong. But I’m certainly an keen advocate for continued (and pro-active) membership. Yes, there are problems, issues, challenges being a member of the EU; no doubt about it. The EU is not a perfect institution, by any stretch of the imagination. Had the UK been a more committed member (rather than carping constantly from the sidelines), then I believe we could have brought much of our renowned British pragmatism to help resolve many of the structural and operational issues that bedevil the EU.

Theresa May’s government is incompetent (more a Coalition of Chaos than Strong and Stable), and while the Brexit ‘divorce’ negotiations are said to have made some progress (although I’m not really sure what), her ministers, especially David Davis, have become increasingly mendacious. Their arrogance and lack of respect for the electorate and facts is truly staggering. The Conservative Party has become a party of ostriches (especially MPs like the honorable member for the eighteenth century, Jacob Rees-Mogg). Furthermore we are being held to ransom by the short-sighted, bigoted, and lack of imagination Democratic Unionist Party (DUP) in Northern Ireland, that May now has to rely on for support in the House of Commons. What a mess we are in.

The lack of focus and understanding in particular over the border issues between Northern Ireland and the Irish Republic are not only worrying but potentially dangerous. In September I spent 10 days in Northern Ireland, and witnessed how that part of the UK has benefited from a couple of decades of prosperity and peace, now in jeopardy because of Brexit.

But a dilemma I face is that I cannot imagine the opposition Labour Party flourishing in government under Jeremy Corbyn, nor can I see myself supporting Labour in an election. I make no bones about it. I am no fan of Corbyn and his closest acolytes. He is not a credible Prime Minister-in-waiting. I regret that he and his party did not take a stronger pro-EU position. His equivocation is reprehensible. I worry for the future of the Labour Party as the left-wing Momentum group strengthens its stranglehold. Likewise, I am no supporter of what the Conservatives now stand for, and its right-wing agenda.

I can only hope that sounder minds will prevail and brought to bear during 2018. Can Brexit be stopped? More from hope than expectation, I think it just might. But will the EU exert a forfeit to allow us back in, requiring the UK to sign up for measures that we have opted out of? Perhaps.

That is my wish for 2018, and although I never make New Year resolutions, I will continue to support pro-EU initiatives as I am able.