Propitious Esculent: The Potato in World History

  • John Reader
William Heinemann: 2008. 315 pp. £18.99 9780099474791 9780434013180 | ISBN: 978-0-0994-7479-1

Propitious Esculent is not just a book about potatoes; it is also about poverty. The two are linked by history, and in this very readable account, anthropologist and journalist John Reader shows us how.

The cultivated potato, Solanum tuberosum, is one of around 1,500 species in the flowering plant genus Solanum, which also includes the tomato, aubergine and woody nightshade. There are some 190 species of wild potatoes, all found in the Andes — from these a single species has been domesticated and spread throughout the world. Those who only see potatoes in heaps at supermarkets may be surprised that the crop comes from a flowering plant and is one of South America's greatest contributions to the European diet. The United Nations Food and Agriculture Organization has declared 2008 the International Year of the Potato to raise awareness of its importance.

Botanically, the potato is a tuber, a swollen piece of underground stem where the plant stores starch. Wild potato plants and local 'primitive' varieties have tubers, but they are often small and oddly shaped, bearing little physical resemblance to those from cultivated varieties. Reader cites recent research on the taxonomy and domestication of these varied and complicated plants. Disappointingly, he does not incorporate recent work on the genetics of the potato and its relatives.

Mash production: potatoes are the world's most chemically dependent crop. Credit: T. MORRISON/SOUTH AMERICAN PICTURES

Nor does the book sufficiently discuss the genetic modification of potatoes for control of disease, an important issue for food poverty. Potatoes are one of the most expensive food crops in terms of pest and disease control. Reader cites the potato as the “world's most chemically dependent crop — with the global cost of fungicides standing at [US]$2 billion per year”. This astounding figure comes almost as a footnote at the end of a long chapter about the discovery of Phytophthora infestans, the agent of potato blight. The fungus, now associated with the devastation of world potato crops, was first discovered in grapevines. Reader's account of the disease, its discovery and its action is riveting, but potatoes are almost incidental to his story. Today, we easily see the connection between symptom and disease and can then search for causative agents: this was not so in the days when people thought microorganisms arose from spontaneous generation.

Reader does detail the development of blight-resistant potato varieties through the plant-breeding work of Redcliffe N. Salaman at the University of Cambridge, UK, in the early twentieth century. But he does not discuss more modern and controversial approaches. Disease control is being developed at the International Potato Center in Peru through 'true potato seed' potatoes — the crop is replanted using the seed from the original potato plant rather than vegetatively propagated from small pieces of tuber. These varieties have great promise for improving the gene pool for disease resistance, especially in the Andes, where genetically engineered potatoes cannot be used because of their potential for hybridizing with wild species.

Reader eloquently argues that social history is important to understand agricultural systems and sustainability. His engaging account of the potato's journey, from the Andes to Europe and beyond, starts and ends in local communities where the tuber is still central to daily life. Andean cultures cultivate potatoes in poor-quality soils at high altitudes, mainly because they have been excluded from richer agricultural land by large landowners and commercial elites. Social factors also influenced the Irish potato famine of the mid-nineteenth century. Potatoes can feed a family well from a very small plot of land, improving offspring survival and thus driving population growth. Pushed onto marginal land by large landowners, Irish peasants nevertheless thrived by growing potatoes; they were desperately poor, but not starving. When the potato blight hit Ireland, the resultant starvation killed more than a million Irish people and led to the emigration of millions more.

In his account of the Irish famine, Reader offers the central message of the book. Eliminating extreme hunger and poverty is one of the United Nations' Millennium Development Goals, but the history of the potato shows us that truly eliminating poverty means much more than ensuring the security of food supplies and avoiding hunger; social equity is equally, if not more, important. Science on its own is no panacea for solving social ills.