Abstract Detail

Reproductive Processes

Narbona, Eduardo [1], Gómez, José M. [2], González-Megías, Adela [3], Navarro, Luis [4], Perfectti, Francisco [5], Armas, Cristina [2], Borghi, Monica [6].

Moricandia arvensis can change its flower color in summer without compromising its conspicuousness.

Flower color variation within species seems to be more common than previously reported, and most of the known cases are due to flower color differences among individuals (i.e. polymorphisms) or floral color changes during flower anthesis. Recently, it has been shown that Moricandia arvensis undergoes a radical change in flower color, size and shape as a result of phenotypic plasticity. During spring, individuals of this species display UV-reflecting lilac flowers, whereas flowers are white lacking reflectance UV in summer. Both types of flowers attract a different assemblage of pollinators; flowers were visited mostly by long-tongued large bees in spring, but mostly by short-tongued small bees, butterflies, and beetles in summer. Here, we aimed to investigate what is the biochemical basis of these two flower color types and how are perceived by their pollinators. Biochemical analysis showed that white flowers did not simply lack anthocyanins, which provide lilac color to the spring flower. On the contrary, white flowers accumulated high amounts of flavonols with important antioxidant capacity. We examined the reflectance spectra of the two types of flowers in four populations and modelled these spectra in the visual system of bees, butterflies and beetles. Both spring and summer flowers showed chromatic values that are highly visible for all the three functional groups of pollinators. However, in the bee visual system, spring flowers showed lower chromatic contrasts than summer flowers. Interestingly, in the butterfly and beetle visual systems, spring flowers showed higher chromatic contrasts than summer flowers. Furthermore, spring and summer flowers had a similar match between reflectance spectra marker points and the maximum discrimination abilities of the visual system of the three pollinator groups, indicating that flower color is not specifically adapted to any pollinator visual system. Together, our results suggest that the white color of summer flowers of M. arvensis may be a way to accumulate protective flavonoids to the stressful summer conditions of the Mediterranean basin without compromising its conspicuousness for pollinators.

1 - Universidad Pablo De Olavide (CIF: Q9150016E), Biología Molecular E Ingeniería Bioquímica, Carretera De Utrera Km 1, Seville, 41013, Spain
2 - Estación Experimental de Zonas Áridas (EEZA-CSIC), Almería, Spain
3 - Universidad de Granada, Dpto. de Zoología, , Granada, Spain
4 - University Of Vigo, Depto. Biologia Vegetal; Facultad De Ciencias;, Campus As Lagoas-Marcosende, Vigo, PO, 36200, Spain
5 - Universidad de Granada,, Dpto. de Genética, Granada, Spain
6 - Utah State University, Department of Biology, Utah, USA

Keywords:
Flower color
Anthocyanins
Flavonoids
Phenotypic plasticity
Brassicaceae
Chromatic contrasts
Visual ecology
plant-pollinator interactions.

Presentation Type: Poster
Number: PRP005
Abstract ID:481
Candidate for Awards:None