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:


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.

He had the patience of Job

21 December 1972. How 45 years have flown by.

I’d left my apartment in Birmingham, said goodbye to many friends in the Department of Botany at The University of Birmingham, and headed the 60 miles north to Leek in Staffordshire to spend what would be my last Christmas in the UK for almost a decade with my parents, my elder brother Ed who had arrived from Canada. Then after Christmas, I spent a couple of days in London with my girlfriend, Steph; we married in Lima later in 1973.

I’d turned 24 a month earlier, and two weeks hence on 4 January 1973 I would be on a flight from London to Lima, Peru to join the International Potato Center (CIP) as an Associate Taxonomist. I can’t deny that I faced that journey and joining CIP with a certain amount of trepidation. I’d only been outside the UK on one occasion (to Turkey in early 1972). My horizons were definitely limited.

Furthermore, I spoke hardly a word of Spanish. Now that was my fault. And it wasn’t. I’d had ample opportunity while at Birmingham once I knew I’d be working in Peru to make an effort to learn some basic Spanish. But I was rather dilatory in my approach.

On the top of the university’s Muirhead Tower, a language laboratory was open to all staff and students to improve, at their own pace, their existing language skills or ones that they wished to acquire. The laboratory was equipped with a number of individual audio booths where you could listen to classes on tape, and follow along with the standard text from which the classes had been developed.

I started, and really intended to continue. Then the only copy of the text book went missing. I gave up.

So, my language skills were essentially non-existent when I landed in Lima on Thursday 4 January 1973. Staying at the Pensión Beech on Los Libertadores in the Lima suburb of San Isidro, I couldn’t even order my breakfast the following morning. Fortunately, Mrs. Beech, the formidable British-born proprietor, came to my rescue. Thereafter I quickly gained enough vocabulary so I didn’t starve. But it was a month or two before I plucked up enough courage to visit a barber’s shop (peluquería) to have my hair cut.

The secretarial and some of the administrative staff at CIP spoke English, and I was indeed very fortunate to receive great support from them, particularly in my first months as I found my feet and started to pick up the language.

All expat staff were offered Spanish classes, provided by freelance teacher Sr Jorge Palacios. And it was that gentleman who had, in my opinion, the patience of Job, listening, day after day, to our pathetic attempts to make sense of what is a beautiful language. Some long-term CIP staff never really did become that fluent in Spanish. I’m sure my old CIP friends can guess who they were.

Unfortunately I don’t have any photo of Sr Jorge*. Yesterday, I placed a comment on a Friends of CIP Facebook group page asking if anyone had a photo. An old and dear friend from my very first days at CIP, Maria Scurrah replied: I certainly remember that thin, never-aging but already old, proper Spanish teacher. And that’s how I also remember Jorge. It was impossible to tell just how old he was, maybe already in his 50s when I first knew him in January 1973.

It was arranged to meet with Sr Jorge at least a couple of times a week; maybe it was more. We agreed that the most convenient time would be the early evening. He would come to my apartment (in Los Pinos in Miraflores), and spend an hour working our way through different exercises, using exactly the same text that was ‘lost’ in Birmingham! Anther colleague who joined CIP within a week or so of me was German pathologist Rainer Zachmann. He also took an apartment in the same building as me. I was on the 12th floor, he on the sixth. So Sr Jorge would call on me, then descend to spend an hour with Rainer, after which we would all go out to dinner at a local restaurant. Through these Spanish classes, and dinner conversation, Jorge introduced me to the delights of Peruvian Chinese cuisine, and there was a good restaurant or chifa just a block or so away from our apartment building, perhaps further along Av. Larco.

It didn’t take long, however, before my classes became intermittent. I was travelling to and spending more time in Huancayo, and in May that year, my germplasm colleague Zosimo Huaman and I spent almost a month exploring for potato varieties in the Departments of Ancash and La Libertad. With the basics that I’d learned from Sr Jorge, and being put in situations where my companions/co-workers did not speak English, I was ‘forced’ to practice—and improve—my rudimentary Spanish.

End of the road – getting to walk into several communities, May 1973

During that trip to Ancash, Zosimo and I found ourselves in a remote village that had been very badly affected by the May 1970 earthquake that had devastated many parts of Ancash. I don’t remember the names or exact locations of the two communities we walked into, except that they were deep in the mountains beyond Chavín de Huantar. It was their fiesta day, and we were welcomed as auspicious visitors, particularly me, as once it was revealed that I was from England, I became a representative of La Reina Isabel (Queen Elizabeth II).

The schoolmaster and his wife and son, with Zosimo Huaman on the right.

A ‘town meeting’ was quickly called and organized by the rather inebriated schoolmaster. Zosimo and I were the guests of honor, and it became clear during the schoolmaster’s speech of welcome that I would have to respond in some way. But what about my lack of Spanish? The schoolmaster explained that the community felt abandoned by the Peruvian government, and even three years on from the earthquake had still not received any material assistance. He implored me to bring their plight to the attention of the British Government and, as the ‘Queen’s representative’, get assistance for them. What was I to reply?

I was able to follow, more or less, what the schoolmaster was saying, and Zosimo filled in the bits I missed. I asked him how to say this or that, and quickly jotted down some sentences on the palm of my hand.

It was now my turn to reply. I congratulated the community on its festive day, stating how pleased Zosimo and I were to be there, and taking note of their situation which I would mention to the British ambassador in Lima (my position at CIP was funded through the then Overseas Development Administration, now the Department for International Development, and I would regularly meet the ODA representative in the embassy, or attend social functions at the ambassador’s residence).

As I sat down, everyone in that room, 150 or more, stood up and each and everyone one came and shook my hand. It was quite overwhelming.

I found that trying to use what little Spanish I had was more useful than having continuous lessons. Nevertheless, the solid grounding I received from Sr Jorge stood me in good stead. When we moved to Costa Rica in April 1976, I had to speak Spanish almost all the time. Very few of the persons I worked with in national programs spoke any English; my two assistants in Turrialba none at all.

By the time I left Latin America in March 1991 I was pretty fluent in Spanish. I could hold my own, although I have to admit that I have never been any good at writing Spanish. During the 1980s when I had a research project with CIP, I travelled to Lima on several occasions. By then, Sr Jorge was no longer freelancing and had become a CIP staff member. We always took time during one of those visits to having lunch together and reminiscing over times past. By the time I visited CIP once again in the mid-1990s he must have retired, as I never saw him again.

My Spanish still resurfaces from time to time. I can follow it quite easily if I hear it on the TV, and during my visit to CIP, CIAT, and CIMMYT in 2016 (as part of a review of genebanks) I was able to participate in the discussions easily enough that took place in Spanish. My Spanish teacher had obviously given me a very good grounding of the basics.

Sr Jorge Palacios – a real gentleman, with the patience of Job.


*  If anyone who reads this post has such a photo, or knows how/where to get hold of one, I’d appreciate hearing from you and receiving a copy. Thank you.

Heading south to the highest lake in the world

At 3812 m above sea level, Lake Titicaca straddles the border between Peru and Bolivia, and is the ‘highest navigable lake in the world’. It’s more than 1200 km south from Lima by road, and was the destination of a trip that Steph and I made in November 1974. Our first idea was to drive to La Paz, the capital of Bolivia, some 256 km southeast from Puno. However, we decided that would be one sector too far in the time we had available.

Most of the drive follows the Panamericana Sur for 850 km through a coastal desert, one of the driest in the world.

The highway crosses the Nazca Plain about 450 km south of Lima, and is the site of the world famous Nazca Lines (yet another UNESCO World Heritage Site in Peru!), ancient geoglyphs that can only be appreciated from the air. Sadly, we never took the opportunity for a flight over the Lines¹.

The Nazca monkey. Photo taken by renowned archaeologist Maria Reiche in 1953.

Much further south, at Camana, the road branches north towards the southern city of Arequipa, some 180 km away, and at an altitude of around 2330 m. Puno is reached from Arequipa after a climb to well over 4000 m before dropping to 3800 m on the shore of Lake Titicaca, crossing (among other locations) the Reserva Nacional Salinas y Aguada Blanca (and its flamingos).

We had already decided to drive ourselves just as far as Arequipa, then take a colectivo (a communal taxi) for the rest of the journey to Puno, and use taxis to move between the various sites we wanted to visit around Puno. On reflection we could have taken our VW the whole distance given some of the other trips we made around Peru and the state of some of those roads. From Arequipa to Puno we left the asphalt behind, travelling on a graded dirt road.

We spent the first night in Nazca, traveling on to Camana and its turista hotel on the second day. Like most of our travels there were frequent stops to admire the landscape, take photos, and investigate the local flora, especially the various cactus species, a particular hobby of Steph’s at that time.

This cactus, possibly an Echinocactus species, was less than 3 inches in diameter.

The highway crosses quite a number of rivers that flow down from the Andes. In the desert, and along the valleys themselves, irrigated rice cultivation is quite important. I had no idea when looking at these rice paddies in the 1970s that I’d be working on that crop across the other side of the world two decades later².

In Arequipa, we found a garage where we could leave the car safely for a few days while we traveled on to Puno. And then spent the next day and a half walking around the city to enjoy some of its sites.

Arequipa, founded in 1540, is (was) an elegant city, with a skyline dominated by the symmetrical cone of the Misti volcano, rising to over 5800 m. It is seasonally snow-capped, but with the effects of climate change affecting so many mountain ranges in the Andes today, I wonder to what extent Misti now has any snow cover at all during the year.

There were two sites we wanted to visit: the Basilica Cathedral, located on the north side of the Plaza de Armas, Arequipa’s central square. It has a facade of beautifully carved white stone, like the cathedral in Cajamarca that we visited in June 1974.

It was constructed over more than two centuries beginning in the 1540s. Progress was interrupted many times by volcanic eruptions and earthquakes, and the church had to be reconstructed several times. As recently as June 2001, one of its towers was toppled by a powerful earthquake that shook southern Peru. It is a building of great beauty, and dominates the Plaza de Armas.

A short distance north of the Plaza de Armas, the 16th century Dominican Convent of Saint Catherine (Monasterio Santa Catalina) is a quiet haven among the bustle of a busy city, and open for tourists to visit. Well, that was the situation four decades ago, so it must be even more so today. It has the feel of a small Spanish village, with winding streets, open doorways off to the side, and colonnaded hidden courtyards. And all decorated in a glorious umber.

The nuns could not receive visitors inside the convent, but could communicate with the outside world through grills. Natural light brightens the visitors’ corridor through skylights hewn from rock crystal. Inside the convent there are beautiful murals dating from as early as 1516. That’s interesting, because in the article about the convent on Wikipedia linked to above, the founding date is given as 1579, and Arequipa was not founded until 1540. Maybe some early buildings were incorporated into the convent. Nevertheless, there are some date inconsistencies I need to check further.

In Puno, there were three attractions we wanted to visit: the harbour and its large steamships; the floating islands made from the local totora reeds (Schoenoplectus californicus subsp. tatora), and home to a community of indigenous Urus; and the pre-Incan archaeological site of Sillustani, some 32 km northwest from Puno towards the airport town of Juliaca.

Some of the vessels that ply (or used to ply) Lake Titicaca are remarkable for their size. So how did they come to be sailing around the lake? The SS Ollanta was built in 1929 in Kingston upon Hull in England, in kit form, and sent out to Peru in pieces. The original Lego! Transported from the port of Mollendo to Puno by rail, it was riveted together on the shore of Lake Titicaca, and launched in 1931. It is still sailing today, but no longer on any scheduled services.

Tourism was, and must still be, a significant source of income for the Uru community that lives on the totora reed islands just offshore from Puno. Steph and I took the short motor boat trip from Puno to spend a couple of hours there. It is quite a remarkable community, seemingly self-sufficient, and getting around on their beautifully-crafted reed boats (the inspiration for Thor Heyerdahl’s Ra II expedition).

Given my interest in potatoes, I was fascinated to come across this brilliant example of potato hydroponics. Now that’s a good use for an old totora reed boat. Ingenious!

Although we didn’t make it into Bolivia, we did head out along the south shore of the lake towards the border, as far as Juli, just over 80 km southeast from Puno. As with so many small communities in the Andes, the town is dominated by a Catholic church, that we took the opportunity of visiting. The opulence of its interior was quite unexpected.

Our final visit in the Puno area was to the pre-Incan cemetery of Sillustani constructed by the Qulla people on the edges of Lake Umayo, and comprising a series of round towers called chullpas. The stones making up the chullpas are smooth and regular is shape, and one is left, yet again, with a sense of awe, at how such beautiful pieces of architecture were actually constructed. Interestingly, the Qulla are an indigenous people of western Bolivia, northern Argentina, and Chile. Sillustani must have been at the northern limit of their territory and range.

And then the vacation was over and we were headed back to Arequipa, to pick up our car and drive to Camana on the coast for an overnight stop. I think we made it back to Lima from there is one very long day of driving.

Besides this visit, I’d been in Puno on two previous occasions. One of my abiding memories was to seemingly acquire a taste for the algarrobina cocktail, made with Pisco. While I love a delicious Pisco sour, the thought of this rather sweet concoction now sends shivers down my spine. Happy days!


¹ The Greenpeace delinquents who staged a protest on and defaced the Lines in December 2014 should have faced the full force of the law.

² In about 1996, the then President of Peru, Alberto Fujimori (now disgraced and serving a prison term for various human rights crimes, among others), visited the International Rice Research Institute (IRRI) in Los Baños, Philippines. I showed him around the genebank, and then joined discussions with IRRI’s Director General George Rothschild about rice production in Peru. Peru grows a number of IRRI varieties that have fallen out of favor in other parts of the world because of their susceptibility to pests and diseases. These, including IR43 and IR48 were less affected in Peru.

In a corner of Pueblo Libre, Lima . . . one of the most important buildings in Peru

In a corner of the Lima suburb of Pueblo Libre, on one side of Plaza Bolivar, the Museo Nacional de Arqueología, Antropología e Historia del Perú (the National Archeological, Anthropological and History of Peru Museum) is arguably one of the most important buildings in Lima. Peru, even. When Steph and I lived in Lima, we visited the museum on several occasions. It looks as though it has had a major face-lift since the 1970s.

It houses one of the finest collections of pre-Columbian artefacts. Anywhere. There are more than 70,000 pieces of ceramic alone. Many must be priceless. These reflect the various indigenous cultures that grew up in Peru (over hundreds and thousands of years) along the coast and in the mountains, before the Spanish arrived in the early 16th century and destroyed them.

As a student of the origins and evolution of crop plants I’m particularly interested in what these fine ceramics can tell us about the crops that dominated ancient cultures. I would relish the opportunity to return and, on this occasion, more carefully document what I saw.

Most of the plants we eat were domesticated from wild plants by farmers thousands of years ago, who developed agricultural systems to grow them and provide food for their families and communities. Peru is the home of many crops important in world agriculture, not least, of course, being the potato. When we begin to look at the origins and evolution of crop plants, we examine the distribution of indigenous crop varieties and where these overlap with the wild species from which they were originally derived. We study their genetic variation patterns, make experimental crosses (pollinations) between crops and wild species to see how inter-related they might be, and compare the offspring with existing varieties. My own research on potatoes, grain legumes, and rice has followed this pattern.

But we also want to be able to track when things happened. And that’s where archaeology and anthropology come into play. In many famous archaeological sites in the so-called Fertile Crescent of the Middle East (one of the earliest cradles of agriculture), carbon-dated remains of cereals are associated with the earliest stages of agriculture, some 10,000 years ago, at a time that is often referred to as the Neolithic Revolution. Archaeologists can tell from these plant remains whether human communities were collecting grains from wild plants or whether they were growing a crop (domesticated cereals, for example, have lost the ability to disperse their seeds, and there are clear anatomical and morphological characteristics that differentiate these from wild plants). Here is an example of such remains (of several crops) from a Central Eurasian site.

The second millennium BC carbonized domesticated crop remains from Central Eurasian seasonal campsites. Tasbas: (a) naked six-row barley, (b) barley rachis, (c) broomcorn millet, (d) green pea (arrow pointing to hilum), and (e) highly compact free-threshing wheat; Ojakly: (f) broomcorn millet, (g) free-threshing wheat, and (h) barley rachises. From: Robert Spengler, Michael Frachetti, Paula Doumani, Lynne Rouse, Barbara Cerasetti, Elissa Bullion, Alexei Mar’yashev (2014) Early agriculture and crop transmission among Bronze Age mobile pastoralists of Central Eurasia. Proceedings of the Royal Society B. Published 2 April 2014.DOI: 10.1098/rspb.2013.3382

But an additional source of information about pre-Columbian cultures and their agriculture in Peru for example can be found in the exquisite ceramics (or huacos) that so many coastal cultures—Chavín, Nazca, Moche, Chimu, among many—left behind, and which have been recovered from graves in the vast cemeteries along the coast.

Many pots have the form of crops grown at that time, 1000 years ago or more, such as potatoes, cassava, lima bean, and many more. There are also representations of animals such as llamas and monkeys. Some ceramics of fruits and vegetables have even taken on human form!

An anthropomorphic potato ceramic

My inspiration was Professor Jack Hawkes, my mentor and PhD supervisor, potato taxonomist extraordinaire! He was fascinated by archaeology, and pre-Columbian archaeology in particular, an interest that he had developed following his first visit to Peru in 1938-39. In this photo, Jack is describing to CIP colleague Jim Bryan, a particularly fine Hauri (Wari)ceremonial urn – just look at the size – decorated around the rim with portrayals of different crops. Can you recognise any? There’s certainly potatoes (Solanum tuberosum) and chili peppers (Capsicum spp.). Maybe even peanuts (Arachis hypogaea).

On a second pot, there’s oca (Oxalis tuberosa) and maize (Zea mays).

If I had been more assiduous 40 years ago I would have carefully noted the details of each pot. But I didn’t. In the gallery below, the brightly painted pots are from the Nazca culture I believe, and the others from the Moche/Huari cultures.

Then there are the ‘other’ ceramics, in a discreet section of the museum (or at least that was the case in the 1970s) of the rather explicit ceramics related to fertility rituals presumably. My, he’s a big boy!

Many of the ceramics were found wrapped inside so-called mummy bundles, buried in the sand of the coastal desert. Bodies were quite well-preserved because of the very dry conditions, and wrapped in beautiful textiles.

On display in the museum there are examples of skull distortion practised by some of these ancient cultures, as well as head surgery or trepanning.

There are also examples of the famous Incan counting string or quipu, and some gold artefacts that I remember, like this solid gold tumi, a ceremonial axe or knife.

In this post I have just lightly touched on the splendour and interest of pre-Columbian Peru.

Peru justly has a proud heritage, both human and crop, that must be cherished. In a small way, and over the decades I have been able to experience these at first hand. No visit to Lima should miss a visit to this national museum.

There are many fake ceramics around for tourists to buy. This is a ‘Mochica’ one that Steph and I purchased while in Lima. Yes, we knew it was a fake, and paid a token amount.

But we liked it, and it has graced a shelf in our homes in Peru, Costa Rica, and the UK ever since.

What if it were genuine? It would be worth a pretty penny.


Outside the EU . . . even before Brexit

Imagine a little corner of Birmingham, just a couple of miles southwest of the city center. Edgbaston, B15 to be precise. The campus of The University of Birmingham; actually Winterbourne Gardens that were for many decades managed as the botanic garden of the Department of Botany / Plant Biology.

As a graduate student there in the early 1970s I was assigned laboratory space at Winterbourne, and grew experimental plants in the greenhouses and field. Then for a decade from 1981, I taught in the same department, and for a short while had an office at Winterbourne. And for several years continued to teach graduate students there about the conservation and use of plant genetic resources, the very reason why I had ended up in Birmingham originally in September 1970.

Potatoes at Birmingham
It was at Birmingham that I first became involved with potatoes, a crop I researched for the next 20 years, completing my PhD (as did many others) under the supervision of Professor Jack Hawkes, a world-renowned expert on the genetic resources and taxonomy of the various cultivated potatoes and related wild species from the Americas. Jack began his potato career in 1939, joining Empire Potato Collecting Expedition to South America, led by Edward Balls. Jack recounted his memories of that expedition in Hunting the Wild Potato in the South American Andes, published in 2003.

29 March 1939: Bolivia, dept. La Paz, near Lake Titicaca, Tiahuanaco. L to R: boy, Edward Balls, Jack Hawkes, driver.

The origins of the Commonwealth Potato Collection
Returning to Cambridge, just as the Second World War broke out, Jack completed his PhD under the renowned potato breeder Sir Redcliffe Salaman, who had established the Potato Virus Research Institute, where the Empire Potato Collection was set up, and after its transfer to the John Innes Centre in Hertfordshire, it became the Commonwealth Potato Collection (CPC) under the management of institute director Kenneth S Dodds (who published several keys papers on the genetics of potatoes).

Bolivian botanist Prof Martin Cardenas (left) and Kenneth Dodds (right). Jack Hawkes named the diploid potato Solanum cardenasii after his good friend Martin Cardenas. It is now regarded simply as a form of the cultivated species S. phureja.

Hawkes’ taxonomic studies led to revisions of the tuber-bearing Solanums, first in 1963 and in a later book published in 1990 almost a decade after he had retired. You can see my battered copy of the 1963 publication below.

Dalton Glendinning

The CPC was transferred to the Scottish Plant Breeding Station (SPBS) at Pentlandfield just south of Edinburgh in the 1960s under the direction of Professor Norman Simmonds (who examined my MSc thesis). In the early 1970s the CPC was managed by Dalton Glendinning, and between November 1972 and July 1973 my wife Steph was a research assistant with the CPC at Pentlandfield. When the SPBS merged with the Scottish Horticultural Research Institute in 1981 to form the Scottish Crops Research Institute (SCRI) the CPC moved to Invergowrie, just west of Dundee on Tayside. The CPC is still held at Invergowrie, but now under the auspices of the James Hutton Institute following the merger in 2011 of SCRI with Aberdeen’s Macaulay Land Use Research Institute.

Today, the CPC is one of the most important and active genetic resources collections in the UK. In importance, it stands alongside the United States Potato Genebank at Sturgeon Bay in Wisconsin, and the International Potato Center (CIP) in Peru, where I worked for more than eight years from January 1973.

Hawkes continued in retirement to visit the CPC (and Sturgeon Bay) to lend his expertise for the identification of wild potato species. His 1990 revision is the taxonomy still used at the CPC.

So what has this got to do with the EU?
For more than a decade after the UK joined the EU (EEC as it was then in 1973) until that late 1980s, that corner of Birmingham was effectively outside the EU with regard to some plant quarantine regulations. In order to continue studying potatoes from living plants, Jack Hawkes was given permission by the Ministry of Agriculture, Fisheries and Food (MAFF, now DEFRA) to import potatoes—as botanical or true seeds (TPS)—from South America, without them passing through a centralised quarantine facility in the UK. However, the plants had to be raised in a specially-designated greenhouse, with limited personnel access, and subject to unannounced inspections. In granting permission to grow these potatoes in Birmingham, in the heart of a major industrial conurbation, MAFF officials deemed the risk very slight indeed that any nasty diseases (mainly viruses) that potato seeds might harbour would escape into the environment, and contaminate commercial potato fields.

Jack retired in 1982, and I took up the potato research baton, so to speak, having been appointed lecturer in the Department of Plant Biology at Birmingham after leaving CIP in April 1981. One of my research projects, funded quite handsomely—by 1980s standards—by the Overseas Development Administration (now the Department for International Development, DFID) in 1984, investigated the potential of growing potatoes from TPS developed through single seed descent in diploid potatoes (that have 24 chromosomes compared with the 48 of the commercial varieties we buy in the supermarket). To cut a long story short, we were not able to establish this project at Winterbourne, even though there was space. That was because of the quarantine restrictions related to the wild species collections were held and were growing on a regular basis. So we reached an agreement with the Plant Breeding Institute (PBI) at Trumpington, Cambridge to set up the project there, building a very fine glasshouse for our work.

Then Margaret Thatcher’s government intervened! In 1987, the PBI was sold to Unilever plc, although the basic research on cytogenetics, molecular genetics, and plant pathology were not privatised, but transferred to the John Innes Centre in Norwich. Consequently our TPS project had to vacate the Cambridge site. But to where could it go, as ODA had agreed a second three-year phase? The only solution was to bring it back to Birmingham, but that meant divesting ourselves of the Hawkes collection. And that is what we did. However, we didn’t just put the seed packets in the incinerator. I contacted the folks at the CPC and asked them if they would accept the Hawkes collection. Which is exactly what happened, and this valuable germplasm found a worthy home in Scotland.

In any case, I had not been able to secure any research funds to work with the Hawkes collection, although I did supervise some MSc dissertations looking at resistance to potato cyst nematode in Bolivian wild species. And Jack and I published an important paper together on the taxonomy and evolution of potatoes based on our biosystematics research.

A dynamic germplasm collection
It really is gratifying to see a collection like the CPC being actively worked on by geneticists and breeders. Especially as I do have sort of a connection with the collection. It currently comprises about 1500 accessions of 80 wild and cultivated species.

Sources of resistance to potato cyst nematode in wild potatoes, particularly Solanum vernei from Argentina, have been transferred into commercial varieties and made a major impact in potato agriculture in this country.

Safeguarded at Svalbard
Just a couple of weeks ago, seed samples of the CPC were sent to the Svalbard Global Seed Vault (SGSV) for long-term conservation. CPC manager Gaynor McKenzie (in red) and CPC staff Jane Robertson made the long trek north to carry the precious potato seeds to the vault.

Potato reproduces vegetatively through tubers, but also sexually and produces berries like small tomatoes – although they always remain green and are very bitter, non-edible.

We rarely see berries after flowering on potatoes in this country. But they are commonly formed on wild potatoes and the varieties cultivated by farmers throughout the Andes. Just to give an indication of just how prolific they are let me recount a small piece of research that one of my former colleagues carried out at CIP in the 1970s. Noting that many cultivated varieties produced an abundance of berries, he was interested to know if tuber yields could be increased if flowers were removed from potato plants before they formed berries. Using the Peruvian variety Renacimiento (which means rebirth) he showed that yields did indeed increase in plots where the flowers were removed. In contrast, potatoes that developed berries produced the equivalent of 20 tons of berries per hectare! Some fertility. And we can take advantage of that fertility to breed new varieties by transferring genes between different strains, but also storing them at low temperature for long-term conservation in genebanks like Svalbard. It’s not possible to store tubers at low temperature.

Here are a few more photos from the deposit of the CPC in the SGSV.

I am grateful to the James Hutton Institute for permission to use these photos in my blog, and many of the other potato photographs displayed in this post.