Plants many plants need insects to pollinate their flowers for reproduction, and they use pigments in many colours to entice visitors. But there’s always room for improvement, and some plants go beyond pigments to engineer the surfaces of their petals to add new colours. Edwige Moyroud and colleagues have looked at the striations on the surface of some petals that can make them iridescent.

“Our initial model predicted that how much cells grow and how much cuticle those cells make were key factors controlling the formation of striations,” said Dr Moyroud, “but when we started to test the model using experimental work in Venice mallow we found out that their formation is also highly dependent on cuticle chemistry, which affects how the cuticle responds to the forces that cause buckling.”
Dr Moyroud added: “Plants are formidable chemists and these results illustrate how they can precisely tune the chemistry of their cuticle to produce different textures across their petals. Patterns formed at the microscopic scale can fulfil a range of functions, from communication with pollinators to defence against herbivores or pathogens. They are striking examples of evolutionary diversification and by combining experiments and computational modelling we are starting to understand a little bit better how plants can fabricate them.”
📰 Press release at Eurekalert.
🔬 Cuticle chemistry drives the development of diffraction gratings on the surface of Hibiscus trionum petals at Current Biology.