A pollen-covered bee on a hibiscus flower petal | Meister Media Worldwide
With progress being made on declining bee populations through breeding and environmental protection methods, there is also interest in better understanding the rationale and methodology behind flower selection from bees and other pollinators. Essentially, what makes bees choose one flower over another?
While the smell of nectar and the color of a flower’s petals have been significant in bee attraction, a new study published through Science Advances reveals that the presence and size of a bullseye pattern on some flowers may play a huge role in drawing in pollinators.
How Flower Bullseyes Are Made
The research for the study was conducted at the Sainsbury Laboratory at the University of Cambridge.
After observing the phenomenon, researchers began a deep dive into petal design. Starting with a hibiscus plant, the team compared plants with similar-sized flowers, but with varying-sized bullseye patterns.
Where it is present, a bullseye pre-pattern appears on surfaces before visible color shows up on a flower’s petal during early development. Dr. Lucie Riglet, the study’s lead author, discovered that the pre-pattern emerges “in a croissant-shaped pattern” long before the bullseye itself matures.
“At the earliest stage we could dissect, the petals have around 700 cells and are still greenish in color, with no visible purple pigment and no difference in cell shape or size,” Dr. Riglet notes. “When the petal further develops to 4,000 cells, it still does not have any visible pigment, but we identified a specific region where the cells were larger than their surrounding neighbors. This is the pre-pattern.”
How Bees See Flower Patterns
Beyond understanding the development of these patterns on flower petals, it’s essential to understand the effect that different types of bullseyes have on pollinators. That led to Dr. Riglet using artificial flowers that mimicked different bullseyes to test pollinator reactions.
“The bees not only preferred the medium and larger bullseyes over the small bullseye, but they were also 25% quicker visiting these larger flower discs,” says Dr. Riglet. “Foraging requires a lot of energy and so if a bee can visit four flowers rather than three flowers in the same time, then this is probably beneficial for the bee, and also the plants.”
While the appeal of the bullseye pattern to pollinators is not entirely understood, the research team, led by Dr. Edwige Moyroud, hypothesizes that the pre-pattern development strategies of these flowers may have deep evolutionary roots, which could account for its influence on flower pattern diversity across species.
How This Discovery Affects the Agriculture and Horticulture Industries
The information uncovered by the study out of Sainsbury Laboratory can help better develop strategies to boost pollinator visits and pollinator efficiency, particularly for plants reliant on pollination.
Additionally, breeders and growers in the agriculture and horticulture industries can use these insights to improve yields through the modification of plant varieties to amplify optimal bullseye patterns that are more attractive to pollinators.
Additional research information and plans for future research into bullseye patterns are expanded upon in the study’s published findings, found in Science Advances.
