In the context of the simultaneous exhibition “8 Objects, 8 Museums“ by the Leibniz research museums, the Senckenberg Naturmuseum in Frankfurt/Main presents how it tracked down the agent responsible for a historic famine.
The potato blight is caused by the oomycete Phytophthora infestans. Oomycetes (sometimes referred to as pseudo-fungi) are more closely related to brown algae and diatoms than to the true fungi. However, similar to the true fungi, they consist of a mesh of cellular threads, the mycelium. If tubers are infected in the soil, the oomycete begins to grow inside the tuber. The interior of the afflicted tuber shows a brownish discolouration and the tubers become inedible – both unappetising and harmful to human health, due to the presence of toxins.
The underside of the leaves on the infected plant is covered with a white layer of fungal hyphae, the so-called “potato mildew”. Here, the sporangia develop, which release spores during wet conditions. This can lead to a rapid spread of the oomycete, particularly during moist weather. While wet conditions damage the potato plants, they favour P. infestans, which requires moisture and moderate temperatures for an effective propagation. During dry weather, there is no risk of infection.
P. infestans made history when the organism that causes the potato blight destroyed large parts of the European potato harvest between 1845 and 1852. Ireland was hit the hardest. The potato constituted the country’s primary food source and was usually planted in monocultures. Therefore, the potato blight that wiped out almost the entire harvest in 1846 and 1847 had catastrophic consequences. The number of people who died of starvation is estimated at around 1 million.
The historical and current samples were compared using modern decoding methods for the genetic material and DNA analysis. The comparison of certain sections of the DNA makes it possible to determine relationships between different organisms. In this process, mathematical algorithms are used to estimate at what time the individual Phytophthora lineages became genetically separated from each other – even beyond the 150-year period in which the samples originated.
For more than fifty years, HERB-1 went on a worldwide rampage; it presumably became extinct, when the first resistant potato plants were cultivated at the beginning of the 20th century. Thus, more than 160 years later, it has finally been revealed which pathogen was responsible for the death of millions of people – and that this pathogen itself became extinct in Europe and the US.
The topics of the exhibitions at the Senckenberg Naturmuseum in Frankfurt/Main (left), which is part of the Senckenberg Gesellschaft, range from the fauna and flora of long bygone times across geology and the development of the Earth to the diversity of modern organisms. In the process, the transformation of habitats over millions of years is clearly illustrated. With more than 38 million objects, the Senckenberg Gesellschaft houses one of the world’s most extensive natural history collections. Most of the objects are not on display; they are used solely for research purposes.
The varied exhibition areas of the Senckenberg Naturmuseum in Frankfurt display countless exhibits. Many of these represent extremely rare or even unique specimens, including a mounted Anaconda, which is among the world’s largest snakes. Shown here is the enormous prey (in this case a Capybara) this snake is able to devour in one piece.
“8 Objects, 8 Museums” is a collaboration project between the Leibniz research museums and the Leibniz-Institut für Wissensmedien in Tübingen in the Leibniz Year 2016.
Research project by the Senckenberg Gesellschaft für Naturforschung regarding »Tubers infected with the potato blight«
All documents and photos:
Senckenberg Gesellschaft für Naturforschung, Photos: Marco Thines, Sven Tränkner
Julius Kühn-Institut, Photo: Thilo Hammann
LIFE Photo Collection
K. Yoshida et al. (2013). The rise and fall of the Phytophthora infestans lineage that triggered the Irish potato famine.
Hertie-Stiftung 2016, Dr. Alexander Grychtolik, Photo: U. Dettmar
Text and object selection: Torsten Collet, Bernd Herkner, Sören Dürr (Senckenberg Gesellschaft für Naturforschung)
Collaboration: Alexandra Donecker, Hildegard Enting, Christina Höfling, Sven Tränkner (Senckenberg Gesellschaft für Naturforschung), Stephan Speicher
Translation: Hendrik Herlyn
Literature: K. Yoshida et al. (2013). The rise and fall of the Phytophthora infestans lineage that triggered the Irish potato famine.