| density-dependent processes in leaf beetles feeding on purple loosestrife: aggregative behaviour affecting individual growth rates. | aggregative responses are commonly observed in insects, including chrysomelids, affecting both individual and population growth rates. in two closely related chrysomelid beetles (galerucella calmariensis and g. pusilla) feeding on purple loosestrife (lythrum salicaria), recent studies suggest that male-produced pheromones may cause both inter- and intraspecific attraction. this paper further examines the causes and consequences of feeding aggregations in these species. olfactometer studies confi ... | 2010 | 20178674 |
| dimethylfuran-lactone pheromone from males of galerucella calmariensis and galerucella pusilla. | male galerucella calmariensis and galerucella pusilla (coleoptera: chrysomelidae) emit an aggregation pheromone while feeding on host foliage. isolation of the compound from collected volatiles was guided by comparisons of gas chromatograms of extracts from males and females and by gas chromatography-electroantennographic detection. the compound was identified by a combination of spectrometric methods and microchemical tests as the novel dimethylfuran lactone, 12,13-dimethyl-5,14-dioxabicyclo[9. ... | 2006 | 16586036 |
| latitudinal variation in resistance and tolerance to herbivory in the perennial herb lythrum salicaria is related to intensity of herbivory and plant phenology. | both the length of the growing season and the intensity of herbivory often vary along climatic gradients, which may result in divergent selection on plant phenology, and on resistance and tolerance to herbivory. in sweden, the length of the growing season and the number of insect herbivore species feeding on the perennial herb lythrum salicaria decrease from south to north. previous common-garden experiments have shown that northern l. salicaria populations develop aboveground shoots earlier in ... | 2015 | 25615739 |
| geographic variation and trade-offs in parasitoid virulence. | host-parasitoid systems are characterized by a continuous development of new defence strategies in hosts and counter-defence mechanisms in parasitoids. this co-evolutionary arms race makes host-parasitoid systems excellent for understanding trade-offs in host use caused by evolutionary changes in host immune responses and parasitoid virulence. however, knowledge obtained from natural host-parasitoid systems on such trade-offs is still limited. in this study, the aim was to examine trade-offs in ... | 2016 | 27476800 |
| differences in cellular immune competence explain parasitoid resistance for two coleopteran species. | the immune defence of an organism is evolving continuously, causing counteradaptations in interacting species, which in turn affect other ecological and evolutionary processes. until recently comparative studies of species interactions and immunity, combining information from both ecological and immunological fields, have been rare. the cellular immune defense in insects, mainly mediated by circulating hemocytes, has been studied primarily in lepidoptera and diptera, whereas corresponding inform ... | 2014 | 25259576 |