Bees are among the most important pollinators of angiosperm plants. Many bee species show narrow host-plant preferences, reflected both in behavioral and morphological adaptations to particular attributes of host-plant pollen or floral morphology. Whether bee host-plant associations reflect co-cladogenesis of bees and their host plants or host-switches to unrelated host plants is not clear. Rop...

In response to pathogen attack, plant cells secrete antimicrobial molecules at the site of infection. However, how plant pathogens interfere with defense-related focal secretion remains poorly known. Here we show that the host-translocated RXLR-type effector protein AVRblb2 of the Irish potato famine pathogen Phytophthora infestans focally accumulates around haustoria, specialized infection str...

Mutualists and pathogens, collectively called symbionts, are ubiquitous in plant communities. While some symbionts are highly host-specific, others associate with multiple hosts. The outcomes of multispecies host-symbiont interactions with different degrees of specificity are difficult to predict at this point due to a lack of a general conceptual framework. Complicating our predictive power is...

Host plant identity and host plant chemistry have often been shown to influence host finding and acceptance by natural enemies but comparatively less attention has been paid to the tritrophic effects of host plant and host plant chemistry on other natural enemy fitness correlates, such as survivorship, clutch size, body size, and sex ratio. Such studies are central to understanding both the sel...

With the swede midge (Contarinia nasturtii) as our main model species, we study two types of olfactory cues that are of importance for gall midges: 1) the pheromones emitted by the female to attract the male; 2) and the host plant volatiles that the females use when finding a host for oviposition. We found that both the blend of compounds and the enantioisomeric form are important for male attr...

1. The dynamics of parasitic organisms depend critically upon the frequency distribution of parasite individuals per host. However, the processes giving rise to this frequency distribution have rarely been modelled and tested for organisms with complex host selection behaviour. 2. In this study Microrhopala vittata, a chrysomelid beetle, was used to investigate how oviposition behaviour, moveme...

Among the many topics of interest to ecologists studying associations between phytophagous insects and their host plants are the influence of natal host plant on future oviposition decisions and the mechanisms of generalist versus specialist host selection behavior. In this study, we examined the oviposition preferences, behavior and larval development of the tomato/potato psyllid, Bactericera ...

the diamondback moth, plutella xylostella (linnaeus, 1758) (lep.: plutellidae) is the most destructive insect pest of crucifer plants throughout the world. in order to study its seasonal population fluctuation, sampling was conducted in the cauliflower fields of south of tehran from late may until october 2011. one hectare cauliflower field in the middle of a large field was randomly selected i...

Suitability of plant tissues as food for insects varies from plant to plant. In lepidopteran insects, fitness is largely dependent on the host-finding ability of the females. Existing studies have suggested that polyphagous lepidopterans preferentially select certain host plant species for oviposition. However, the mechanisms for host recognition and selection have not been fully elucidated. Fo...