It is an enriching interaction. Without insects, plants would not be what they are (or what they are). Plants evolve thanks to insects. Researchers from the University of Zurich clarify this. They describe how they benefit from a greater variety of interactions with pollinators and herbivores.
Plants that are pollinated by insects and have to defend themselves from herbivores were studied. They adapt better to different types of soil. Plants obtain nutrients and water from the soil. Different types of soil differ in their chemical and physical composition. Therefore, plants must adapt their physiology to optimize this process in different types of soil, reports the University of Zurich.
Adapting to the ground
This evolutionary process leads to the formation of ecotypes. That is, locally adapted “plant races.” They differ slightly in appearance and can no longer easily interbreed. This last effect is considered the first step towards the formation of separate species. Adapting crops to local soil types is also crucial for agricultural productivity.
A team of researchers led by biologist Florian Schiestl from the University of Zurich describes it. The interaction of plants with pollinators and herbivorous insects influences their adaptation to soil types. And, therefore, in the formation of ecotypes. It’s a two-year experiment. About 800 turnip plants were grown in different types of soil in a greenhouse for 10 generations. One group was pollinated by bumblebees, another by hand. Additionally, plants were grown with and without aphids (as herbivores).
At the end of the experiment, the researchers compared the soil adaptation of the plants. Bumblebee-pollinated plants showed clear differences between soil types. While the groups of hand-pollinated plants remained practically the same.
Evolution
There was significant adaptation only in plants pollinated by bumblebees with aphids after the two years of experimental evolution. No significant adaptation to soil type was observed in the other groups.
Another factor indicates that plants evolve thanks to insects. The study identified several genes that may play a critical role in this adaptation process. It was concluded that adaptation is more efficient when plants are exposed to a variety of interactions.