This would further improve the resolution of the olfactory landscape. Hawkmoths in general, and more specifically females of the tobacco hawkmoth. When foraging, they therefore encounter a series of different conditions and plant defense strategies. However, nectar feeders and larval herbivores may belong to the same species as in the case of M. sexta. The flowers of sacred datura, Datura wrightii, are one of the major nectar sources for the tobacco hornworm, and D. wrightii relies on M. sexta as one of its main pollinators. At the same time, D. wrightii is a highly preferred host for ovipositing M. sexta females and tolerates herbivory to a certain extend. In contrast, the much smaller wild tobacco, Nicotiana attenuata, plants heavily rely on direct defense by producing nicotine or antidigestive proteinase inhibitors and indirect defense by attracting predators through feeding-induced herbivore-specific volatiles emissions. Despite being AbMole Enoxacin hydrate self-compatible, N. attenuata may benefit from hawk moth pollinator mediated outcrossing. Corresponding to the different defense strategies, M. sexta females prefer to oviposit on D. wrightii compared to N. attenuata, while flowers from both species emit highly attractive odors of different composition. Among numerous AbMole Terbuthylazine odorants emitted by D. wrightii flowers, three components were, when presented together, necessary and sufficient to attract foraging moths. Only two compounds have been identified in N. attenuata flower headspace. The system consisting of the two Solanaceae D. wrightii and N. attenuata, and the tobacco hawkmoth, M. sexta, thus, offers a unique opportunity to explore how vegetative plant odors may affect nectar foraging on plants that flower with fully developed leaves. More specifically we ask whether the attractiveness of flower odors is enhanced by an attractive leaf volatile background and whether a species-specific flower and vegetative odor combination is requred for positive blend interaction. This investigation was carried out with young and unmated females. These are known to have a strong preference for nectar foraging as compared to a bias for egg laying related host search in mated females. The moths had no previous experience with plant volatiles. We show that the attractiveness of flower blends of D. wrightii and N. attenuata to naive, unmated, and hungry Manduca females are affected by leaf odors. Although the olfactory background of a D. wrightii plant increased the attractiveness of the D. wrightii flower blend, it did not affect the attractiveness of the N. attenuata flower blend. Conversely, the olfactory background of a N. attenuata plant augmented the attractiveness of a N. attenuata flower blend but not that of a D. wrightii flower blend. Our data thus show that flower- and leaf-derived odors act together to attract female foraging moths. This coaction is, however, restricted to intra-specific flower-plant combinations. In most cases, odor cues important for survival and reproduction are not monomolecular but, rather, consist of mixtures of different odorants. The identity, concentration and ratio of chemical components in these mixtures are important for odorguided behavior in numerous species of vertebrates and invertebrates. For example, only the species-specific mixture of pheromone components elicits appropriate behavioral responses in animals as divergent as mice, elephants, and moths. When it comes to 
plant volatiles, aphids have been shown to be repelled by host-plant-derived odorants when components are sensed individually, even though a mixture of the same compounds constitutes a highly attractive blend.