Septoria krystynae is a newly discovered species of microscopic fungus that can save Polish and European forests from the increasingly spreading mistletoe. Research on the fungus is conducted by scientists from the Faculty of Biology and Environmental Protection of the University of Lodz and the Institute of Forest Sciences of the Bialystok University of Technology.
Mistletoe, primarily associated with Christmas, is in fact a semi-parasitic plant that has been spreading rapidly in Europe in recent years and is a growing threat to forest farming. It causes huge damage to forests, orchards and plantations.
'Until recently, mistletoe was observed primarily on deciduous trees, such as poplars and lindens, but in recent years this parasite has begun to seriously spread to conifers: pine and fir. Foresters are sounding the alarm, especially that pine is the main tree cultivated in our country', explains Professor Małgorzata Ruszkiewicz-Michalska from the Department of Algology and Mycology, Faculty of Biology and Environmental Protection, University of Lodz.
Scientists suspect that the expansion of mistletoe to conifers is related to climate change.
'The development of mistletoe on a pine tree leads to the death of trees, because the parasite not only draws water and mineral salts from the host tree, but also facilitates access for other pathogenic organisms, as well as bark beetles. Fighting mistletoe is very difficult, unfortunately the current methods of mechanical removal and chemical agents are only partially effective', adds Sebastian Piskorski from the Department of Algology and Mycology, University of Lodz.
In many countries, biological methods of combating pathogens with parasites have been recognized as beneficial and safe for the environment. So far, several species of microscopic fungi that parasitise mistletoe are known. However, none of them have been sufficiently studied and used to develop a biological agent to combat this parasite.
In the spring of 2022, scientists from the Faculty of Biology and Environmental Protection of the University of Lodz and the Institute of Forest Sciences of the Bialystok University of Technology started the research project 'Fungi that limit the growth of common mistletoe'.
'This is the first stage of the project to search for fungal species that will be pathogenic for mistletoe, and thus limit its growth and spread', explains Professor Małgorzata Ruszkiewicz-Michalska.
'We collect mistletoe plants from all over the country and check whether they have disease symptoms. If the disease is caused by fungi, we grow them on artificial substrates in laboratory conditions in order to subject them to microscopic analysis and genetic testing', adds Sebastian Piskorski.
During the research project, scientists managed to discover and describe a new species of microscopic fungus Septoria krystynae. This fungus was found in the Białowieża Forest by Marek Wołkowycki from the Institute of Forest Sciences of the Bialystok University of Technology. It is a parasite of common mistletoe and causes leaf spot disease.
'Whether the newly described species can be effective in combating mistletoe in Polish forests depends on many factors. First, the pathogenicity of this fungus and its effectiveness should be examined using various methods of application', emphasises Professor Małgorzata Ruszkiewicz-Michalska.
'Remember that a fungus is not a chemical agent that we apply and get 100% effectiveness. Fungi are living organisms that can mutate and adapt to new conditions. Relatively recently, scientists discovered that fungi can +borrow+ fragments of genes from other organisms (bacteria, plants, animals, chromists and other fungi) and incorporate them into their own DNA. This phenomenon is called horizontal gene transfer. This ability allows fungi to more easily adapt to the physiology of these organisms and parasitise them more effectively. However, it is easy to imagine that this ability can also be dangerous, which is why detailed research is necessary before fungi can be used to fight parasites', the biologist explains.
As part of their research, scientists from the University of Lodz and the Bialystok University of Technology plan to study the entire mycobiota of common mistletoe growing on trees in Polish forests. Thanks to the comprehensive results of these observations, it will be possible to carry out pathogenicity tests for various species of fungi in relation to mistletoe. (PAP)
PAP - Science in Poland, Bartłomiej Pawlak
bap/ ann/ kap/
tr. RL