Significance of floral colour and scent in three Solanum sect. Cyphomandropsis species (Solanaceae) with different floral rewards

Abstract

The role of scent and floral colour in three Solanum sect. Cyphomandropsis species with different floral rewards was studied. In the two studied species with pollen rewards, S. glaucophyllum Desf. and S. stuckertii Bitter, the principal advertisement to pollinators is the colour of the perianth and anthers, including areas that absorb UV light. In the last species, the scent emitted by the osmophores of the connective also plays a significant role in flower attraction. The floral perfume would be the only advertisement in species such as S. adelphum Morton, with perfume reward in which the cryptical anther colour does not contrast with that of the perianth. The internal face of the petals remains hidden. In this case no differences in the patterns of areas that absorb visible light and UV light were found. The main visitors to Solanum are species of Bombus and Augochloropsis. These pollinators visit S. glaucophyllum and S. stuckertii, species with pollen reward, but they do not visit flowers with perfume reward, for example S. adelphum.