Potato Power: The Humble Tuber Helps Promote Food Security

Whether you enjoy rösti, kartosnik, gnocchi, latkes, or blinis, you are consuming a popular tuber otherwise known as the potato. This nutritious vegetable with more than 1,000 edible varieties has its origin in the Andes. It is there, the home of “Parque de la papa” (the Potato Park), that the International Potato Center maintains the world’s largest gene bank of potato germplasm from at least eight Latin American countries and 3,800 traditional Andean cultivated potatoes (www.potato2008.org).

The United Nations designated 2008 as the “International Year of the Potato” to make a valid and effective contribution toward meeting the Millennium Development Goals, which include food security, poverty alleviation, and sustainable use of biodiversity.

Today, the potato is grown in 149 countries from 65 degrees north latitude to 50 degrees south latitude, from sea level up to more than 4,000 meters, and has become the world’s fourth-most-important food crop (after wheat, maize, and rice). World production of this biodiverse food exceeded 325 million metric tons in 2007.

The United States produces only 28% of the world’s mass of potatoes, yet is one of the largest consumers of this vegetable per capita at 57 kg/year. Asia, on the other hand, consumes almost 50% of the world’s potato supply, yet with a modest 24 kg per capita annual consumption. Several Asian countries, including China and India, rely on the potato as a steady source of income. About a third of U.S. potatoes are consumed fresh, 60% are processed (into frozen products, chips, starch, and dehydrated potato), and approximately 7% are re-used as seed potatoes.

The distribution of the potato reflects adaptation to a wide range of growing conditions, temperature, and the availability of water. The downside to this adaptation, is that the potato, as a single species, Solanum tuberosum, tender and highly bred, has become utterly dependent on its cultivators for survival against climate changes, resistance to pests and diseases, marginal land conditions, and agricultural practices (Reader, 2008; Priest, 2009).

The potato is a very productive plant. Far more of its total biomass can be eaten than is the case with other food crops. Among cereals, for example, the edible grain amounts to only about one-third of the mature plant’s weight, while edible tubers comprise more than three-quarters of a potato plant (Salaman, 1985). This means that potatoes produce more energy/day on a given area than any other crop and are, therefore, a most-efficient means of converting plant, land, water, and labour resources into a nutritious and palatable food.

Perhaps the potato’s most important and least appreciated asset in developed countries is its nutritional value: It is low in fat (<0.1%), cholesterol-free, and rich in complex carbohydrates (~16%) and several micronutrients, particularly potassium (>400 mg). The raw white spud also provides about 20 mg vitamin C and nearly 10% of the daily value of dietary fiber per 100 g.

The protein content of a potato is low (~1.5%) compared with grains (durum wheat ~14%), yet, on a dry-weight basis, the protein content of a potato is similar to that of cereals and is very high in comparison with other roots and tubers (www.potato2008.org/en/potato/factsheets.html).

These and other attributes of the potato are so compelling that this vegetable is one of the crops NASA agronomists have chosen for the Bioregeneration Life Support System that began development in the mid-1980s. In this case, white and sweet potatoes are on the list of crops that space crews will grow, harvest, and maintain in the Astroculture^TM unit for food and waste management as well as for scrubbing the atmosphere of unwanted CO₂ during long-term space missions (Yorio et al., 1998; Cook et al., 1998).

The potato genome sequencing consortium is an international cooperation of nationally backed scientific research institutes committed to collaboratively sequence the entire potato genome (850 Mbp) by the end of 2010 in order to improve the crop’s sustainable traits influenced by multiple genetic and environmental factors. New crops will be more disease-resistant to reduce pesticides in agriculture (Bachem, 2008). These new crops represent a major contribution to eradicating extreme world poverty and hunger.

So next time you head out to the local store for some spuds, you can rest assured that when it comes to the value of the potato, there is a lot more than meets the eye.

References for the studies cited above are available from the authors.

Roger Clemens, Dr.P.H.,
Contributing Editor
Scientific Advisor, ETHorn, La Mirada, Calif.
[email protected]

Evie Serventi,
Contributing Editor
Deputy Editor, Crier Media Group, London
[email protected]