Chemical attractiveness of night-flowering Caryophyllaceae of the Silene otites group to flower visiting mosquitoes
Grako678 C4From 01/2004 to 12/2007
Staff: Sigrid Liede-Schumann, Konrad Dettner, Gregor Aas, Stefan Dötterl
Pollinator attractants are recognised in a number of diverse chemical classes, and some volatiles components of flowers have been proven to be attractive and elicit both chemosensory and behavioural responses in pollinators. Although floral odors are ephemeral they are more informative than visual or auditory cues and convey superficial information about species identity and patch size. Floral scent might also be important for the selection of host plants. The importance of mosquitoes as nocturnal pollinators is mostly unknown but in some cases they were observed or postulated as pollinators in some plants. For most mosquito species, floral nectars are important carbohydrate sources due to which they feed on plant sugars. The ubiquity of this activity has been verified by different researchers studying mosquitoes in relation to plant sugar. At specific times in a mosquitoe’s life, nectar sources are not as attractive as blood sources but sugar feeding is usually necessary and more frequent than blood feeding. Therefore, mosquitoes respond to the odors of a wide range of flowers and extra-floral nectar sources for sugar-feeding. Moreover, their flight and landing are triggered by floral odors even in absence of visual stimuli. In Europe, pollination by mosquitoes is rarely found. However, the rather inconspicuous flowers of Silene otites (L.) Wibel with their small yellow to green petals are pollinated by mosquitoes and small moths. We are actually interested to know the floral odor composition in mosquito pollinated plants as well as the specific floral odor compounds attracting mosquitoes. Therefore, our on going research project has been aimed to: i) compare the floral scent composition of plant species pollinated by mosquitoes, especially in the Silene otites group by dynamic headspace and GC-MS analysis, ii) identify floral key compounds responsible for the attraction of mosquitoes by wind tunnel bioassays, EAG and GC-EAD analyses.