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BRS Marco Todesco: UV patterns in wild sunflowers: one gene and two functions.
September 15, 2021
host: Rieseberg Lab
Title: UV patterns in wild sunflowers: one gene and two functions.
Abstract: While all sunflowers appear uniformly yellow to the human eye, they display extensive variation for floral ultraviolet (UV) patterns. UV patterns have long been known to be important for attracting pollinators (most of which can see in the UV) – but how and why are they so variable? We found that regulatory variation at a single transcription factor (HaMYB111) controls most of the diversity for floral UV patterns in wild sunflower (Helianthus annuus), by regulating the accumulation of flavonol pigments. This diversity affects pollinator preferences, but is also strongly correlated with environmental factors (relative humidity and temperature) across the range of this species. Consistent with this, larger ultraviolet patterns, which are found in drier environments, limit transpiration, therefore reducing water loss. This dual role of floral UV patterns in pollination attraction and abiotic responses reveals the complex adaptive balance underlying the evolution of floral traits.
Biodiversity Research Seminar Series (BRS)