Posted on28. June 2022, 04:38
While studying teas and herbs available on the market, the team from the University of Trier found traces of the genetic makeup of several hundred insects. A new method made it possible.
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A research team from the University of Trier found DNA from up to 400 different species of insects in tea bags and tea herbs.
Unsplash
Traces of DNA get into teas quite accidentally: if a bee flies to a flower to pollinate it, it leaves a little saliva.
Pexels
The bugs become permanent in the leaves when they sting.
Wikimedia Commons / jacilluch / CC BY-SA 2.0
Scientists from the University of Trier in Germany have developed a method to extract and evaluate genetic traces of insects from dried plants. “We researched commercial teas and herbs and found DNA of up to 400 different species of insects in one tea bag,” said Henrik Krehenwinkel, biogeographer and junior professor.
When a bee flies to a flower to pollinate, it leaves a little saliva. The worm stings the leaf, the spider leaves silky strands. According to Krehenwinkel, all this is already enough to detect insect DNA. Eggs or excrement are also suitable traces for a biogeographer. There is still a need to investigate whether there is a limit to what can be detected. “In principle, however, single cells, such as beetle cells, will probably suffice,” explained Krehenwinkel.
“We researched commercial teas and herbs and found DNA of up to 400 different species of insects in one tea bag.”
Henrik Krehenwinkel, junior professor at the University of Trier
New opportunities
According to the University of Trier, the innovation of the method developed by Henrik Krehenwinkel, Sven Weber and Susan Kennedy is that environmental DNA (eDNA) is not taken from the surface of plants as usual, but from crushed, dried plant material. “Drying seems to protect DNA particularly well,” explained Krehenwinkel.
“Now we can also prove which insects live inside the plant.”
Henrik Krehenwinkel, junior professor at the University of Trier
eDNA is not available for a long time in the plant shell because it is degraded by UV light or washed away by rain. Another limitation is that mainly insects on the plant surface are considered. “Now we can also prove which insects live in the plant,” explained Krehenwinkel.
Important when it comes to insect mortality
According to the scientist, the method presented in the specialist journal “Biological Letters” opens the possibility of analyzing old plant populations, e.g. from museums, and comparing their colonization with today’s. “In this way, one could find out what the insect community looked like years ago, when the plant was harvested, and what it looks like on the site today.” This is especially important due to the mortality of insects.
(DPA, fee)