Like human beings and animals, plants are subject to diseases. In order to maintain a sufficient food supply for the world's population, it is essential for those involved in plant growth and management to find ways to combat plant diseases capable of destroying crops on a large scale. There are more than 50 000 diseases that are associated with plants.



Since 1990 Plantovita has played an important role in the identification and detection of harmful and specific diseases for both the potato and dry bean industries. Planting material presented for certification is tested by Plantovita for the presence of specific bacterial, fungal and virus diseases. The object of these investigations is to determine whether the planting material submitted, complies with the disease tolerances as prescribed in the respective certification schemes. The benefit of these tests entails the detection and quantification of harmful diseases which may occur in seed material, even latently.

Plantovita is registered with the Department of Agriculture in terms of the Plant Improvement Act, 1976 and managed in accordance with prescribed control measures. The laboratory enjoys the approval of the Independent Certification Council for Seed Potatoes for the detection of specific diseases on seed-lots presented for certification. Plantovita is one of five testing laboratories in the potato industry and fulfils the unique and valuable role as the controlling laboratory of the potato industry.

Why a controlling laboratory?

In an industry there should be a centre of expertise controlling the consistency of the tests performed by different laboratories and operators by means of scientific procedures, standardisation and training. In the case of the potato industry this is necessary for the effective implementation and credibility of the South African Seed Potato Certification Scheme.


A grower who presents registered seed-lots for certification must be sure that –

  • the test results in respect of a specific sample tested at any of the laboratories approved by the Independent Certification Council for Seed Potatoes will be comparable; and
  • the test results will reflect the disease content of the specific sample with due consideration of the limitations of the ELISA test and variation in sampling methods.

In order to maintain the balance between the test results of the regional laboratories and the credibility of the testing process, it is the responsibility of Plantovita as controlling laboratory to ensure that –

  • the best internationally available ELISA test kits are used;
  • the test protocols are continually updated and that the procedures are carried out properly; and
  • all the laboratories function in accordance to international standards.

To achieve this it is furthermore, the responsibility of Plantovita to –

  • make recommendations with regard to the replacement of worn out laboratory equipment and/or the purchasing of new equipment;
  • submit proposals with regard to an expansion or improvement of a facility if work procedures and turnover justify such expansion or improvement;
  • ensure that the personnel of Potato Laboratory Service are properly and continuously trained to be able to perform tests independently;
  • equip the personnel of Potato Laboratory Service with the essential knowledge to be able to manage the laboratories and personnel attached thereto in accordance with legal requirements;
  • audit the respective regional laboratories, to make recommendations and to follow up corrective actions in order to control quality and to standardise procedures;
  • implement inter-laboratory tests nationally in order to monitor the comparability of regional laboratories with a view to quality control and standardisation; and
  • provide technical assistance and support if testing problems are experienced in a laboratory until the problem has been solved successfully.

The ultimate object of the afore-mentioned actions is to ensure that all the official testing laboratories of the potato industry enjoy and maintain the approval of the Independent Certification Council for Seed Potatoes and Departmental registration.

Did you know?

Potatoes first arrived in Spain from South America in 1570 and slowly spread to the rest of Europe during the late 1500s. But the potato didn’t receive a warm welcome and was regarded with suspicion, distaste and fear and was considered to be unfit for human consumption. Peasants refused to eat the ugly misshapen tubers produced by a plant originating from a heathen civilization. The resemblance of the potato plant to plants in the nightshade family hinted that it was created by devils and witches.

In northern Europe potatoes were primarily grown in botanical gardens as an exotic novelty. In France people only overcame their distaste in 1700 when Louis XVI began to sport a potato flower in his buttonhole and Marie Antoinette wore the purple blossoms in her hair. Both Catherine the Great of Russia and Frederick the Great of Prussia had to face the challenge of overcoming the nations prejudice against the plant. Across the Atlantic potatoes received the royal approval when Thomas Jefferson served them to guests at the White House. And so, potatoes steadily gained in popularity.

By including potatoes in food production, farmers were able to produce more food and soon discovered the protection they gained against the catastrophe of grain crop failure which often led to periodic population checks caused by famine. The highly nutritious potatoes also helped mitigate the effects of diseases such as scurvy, tuberculosis, measles and dysentery. The potato is remarkable for both its adaptability and its nutritional value. As well as providing starch, potatoes are rich in vitamin C, high in potassium and an excellent source of fibre.

Historians debate whether potatoes directly encouraged a tremendous population explosion wherever it travelled due to higher birth rates and lower mortality rates. In the late 1700 England and Wales found potatoes to be the answer to food problems caused by an ever increasing percentage of the populace crowding cities on the brink of the Industrial Revolution. Between 1801 and 1851, both countries experienced an unprecedented population explosion, doubling the combined population to almost 18 million.

France experienced at least 40 outbreaks of serious nationwide famine between 1500 and 1800 until the sudden shift towards potato cultivation in the early years of the French Revolution. This allowed a nation which traditionally hovered on the brink of starvation in times of peace and stability to expand its population during decades of constant political upheaval and warfare.

In Ireland the potato became a staple by 1800. The Irish population doubled between 1780 to 1841 without any significant expansion of industry or reform of agricultural techniques beyond the widespread cultivation of the potato. The abundance provided by potatoes greatly decreased infant mortality and encouraged early marriage. Contemporary visitors painted the Irish as a people remarkable for their health and prone to serve potatoes for appetizer, dinner and desert.

By 1815 the potato had become a staple food in the diets of most Europeans.

At the beginning of the 21st century potatoes have now become the fourth most important staple food worldwide, after rice, wheat and maize. While in many industrialized nations potato consumption has been declining for a number of years, the opposite trend can be observed in developing countries. Again the spud is on its way to becoming a real staple food of global importance. History has shown that it helps to combat hunger and poverty wherever it is cultivated.

During a scientific expedition to Patagonia, Charles Darwin, the British naturalist, made the following observation about a surprisingly adaptable South American plant: It is remarkable that the same plant should be found on the sterile mountains of Central Chile, where a drop of rain does not fall for more of six months, and within the damp forests of the southern islands

The plant Darwin observed was the potato.