In a surprising experiment, scientists from France’s National Center for Scientific Research (CNRS) and the University of Montpellier observed the effects of selective pressure on flowering plants. By comparing today’s pansy flower varieties grown in the Paris region with pansy flower varieties regrown from seeds of the same variety collected in the 1990s and 2000s, researchers found that a remarkable I observed the difference.
Study co-author Pierre-Oliver-Spout said plant evolution during this period led to a 25% increase in self-pollination (or self-pollination) in the two modern plants. “We also noticed a 10% reduction in flower size and a 20% reduction in nectar production, which indicates a reduction in rewards for pollinators such as bumblebees. “It suggests,” he said.
To confirm this result, Cheptu and his colleagues conducted behavioral tests on bumblebees that “prefer their ancestral plants,” Cheptu said.
He added that the study shows the impact of pollinator decline on the reproductive systems of these plants.
When father and mother are the same plant
Samson Akoka-Pidor, lead author of the study, detailed the experimental methodology and said the researchers used “resurrection ecology.” This included plant seeds from the 1990s and 2000s that had been collected from fields in the Paris region and stored in refrigerators. 2 plant greenhouses. “In 2021, we went to the same fields to collect seeds of descendants of the same flowering plants,” he said. In the study, all plants were grown in a greenhouse at the same time of year to ensure consistency.
To determine self-pollination rates of ancestor and descendant varieties, the research team used a classic molecular technique of measuring how often individual plants have stretches of chromosomes that carry the same version of a gene, Cheptou said. It is said that he used it. This often occurs in self-pollination, since the maternal and paternal copies of the chromosomes are obtained from the same individual.
Akoka Pidor said the research team was surprised by the speed at which plants evolved in their natural environment. “Pollinator decline is already significant, and it appears that there is already selective pressure on this species. Another important aspect of this result is that we are currently in a position where we have “We are observing a breakdown in human interaction,” he added.
Acocapidor said the study suggests pollinator declines may be self-reinforcing. “We can predict that if plants produce less nectar, there will be less food for pollinators, which could lead to further pollinator declines,” he said.
Everything is a trade-off
This adaptation is not necessarily beneficial for the plant. “It depends on the time scale on which we consider this adaptation as an answer to selection pressures. Over the long term, we find that self-pollinating species have higher extinction rates than outcrossing species,” he says.
Although the study was limited to a single plant species, Cheptow suspects that similar evolutionary adaptations may be occurring in other species. “We should expect this result for any plant that can practice at least a little self-pollination. But this needs to be confirmed by experiment,” he said.
Cheptou said future research should investigate whether similar patterns exist elsewhere in Europe for this plant species to see if similar adaptations have occurred in other species. It means.
“Another interesting aspect is to see if the future evolution of plants is reversible, so that they will once again become more attractive to pollinators and less likely to self-pollinate. ”Acocapidor said.
New Botanist, 2023. DOI: 10.1111/nph.19422
