Allergic ragweed thrives particularly well in Europe
Mugwort ambrosia will spread more widely in Europe than previously thought. This was the result of a study by the Biodiversity and Climate Research Center (BiK-F) and the Goethe University Frankfurt. This is bad news especially for allergy sufferers, since the pollen of the ragweed is one of the strongest allergy triggers. The plant is also a late bloomer and only releases its pollen from late summer to autumn or even December. For allergy sufferers, this significantly increases the time of suffering.
Ambrosia benefits from climate change “Like many invasive species, the ragweed benefits from climate change. But it has probably also changed evolutionarily, ”reports Oliver Tackenberg from Goethe University Frankfurt, who carried out the project in cooperation with the BiK-F. The European version of the ragweed is more developed and more vital than in America, the country of origin of the plant. Not only are the seeds significantly larger, their germination rate is also 92 percent, almost twice that of American populations. In addition, the European young plants had a more pronounced frost tolerance.
One reason for the vitality of ambrosia in Europe could be that its natural enemies are missing in this country. “This means, for example, that the production of chemical antibodies is no longer necessary. The released resources can be put into reproduction and lead to faster growth and increased competitiveness in the form of larger seeds, ”explains Tackenberg. "Why the European stocks of ragweed ragweed seem to be more competitive, however, can only be clarified by further investigations."
Spreading the ragweed could cost healthcare up to € 1.19 billion a year. Researchers are urgently calling for a national strategy to stop the plant from spreading, which is one of the 100 most problematic invasive species. “So we have to take action as soon as possible. So far, only selective measures against mugwort ambrosia have been taken, ”emphasizes the first author of the study, Marion Leiblein-Wild from BiK-F. “Each federal state deals with the topic differently. With a view to the damage to health, however, we need a concerted, national control strategy, such as that which exists in Switzerland. There, not only farmers or gardeners are legally obliged to report occurrences of ambrosia, but every single citizen. With us, the government is still relying on voluntary help, although experts are already assuming that ambrosia allergies will result in additional healthcare costs of up to EUR 1.19 billion per year. ”(Ag)