| the endocrine control of adult reproductive diapause in the chrysomelid beetle galeruca tanaceti (l.). ii. | | 1965 | 14288375 |
| enemies in low places - insects avoid winter mortality and egg parasitism by modulating oviposition height. | oviposition site selection in insects is essential in terms of low egg mortality, high offspring survival and therefore a high reproductive output. although oviposition height could be a crucial factor for the fitness of overwintering eggs, it has rarely been investigated. in this study the oviposition height of a polyphagous leaf beetle, galeruca tanaceti linnaeus in different habitats and at different times of the season was examined and its effect on egg clutch mortality was recorded. the lea ... | 2006 | 16923200 |
| defensive components in insect eggs: are anthraquinones produced during egg development? | eggs of several insect species are protected against natural enemies by noxious components. however, almost nothing is known about the fate of these defensive substances during egg development nor their site of biosynthesis. the eggs of several leaf beetle species of the taxon galerucini contain components that are unusual in insects: 1,8-dihydroxylated anthraquinones and anthrones that deter predators such as ants and birds. these components, i.e., the anthrones dithranol and chrysarobin, and t ... | 2006 | 16835809 |
| presence of wolbachia in insect eggs containing antimicrobially active anthraquinones. | wolbachia are obligatory, cytoplasmatically inherited alpha-proteobacteria, which are common endosymbionts in arthropods where they may cause reproductive abnormalities. many insects are well known to protect themselves from deleterious microorganisms by antibiotic components. in this study, we addressed the question whether wolbachia are able to infect insects containing antimicrobial anthraquinones and anthrones, and if so, whether these genotypes of wolbachia comprise a monophyletic cluster w ... | 2007 | 17364245 |
| anthraquinones as defensive compounds in eggs of galerucini leaf beetles: biosynthesis by the beetles? | eggs of leaf beetles of the tribe galerucini, subfamily galerucinae, contain polyketides that are unusual in insects: 1,8-dihydroxylated anthraquinones (chrysazin, chrysophanol) and anthrones (dithranol, chrysarobin) deterring predators. the host plants do not contain these compounds. in the present study, we tested the hypothesis that the beetles, but not bacterial or fungal microorganisms living as endosymbionts within the beetles, produce the anthraquinones. the tansy leaf beetle galeruca tan ... | 2007 | 17879233 |
| diet dependent experience and physiological state shape the behavior of a generalist herbivore. | the performance of herbivorous insects depends on a balance of nutrient uptake and toxin avoidance. whereas high concentrations of defensive plant metabolites impair both generalists and specialists, generalists are likely less adapted to particular hosts and thus more negatively affected by plant defense traits. furthermore, resulting diet-dependent differences in the physiological state and the gained experience of an animal may shape its behavior. here, we investigated the effects of life-lon ... | 2014 | 24576678 |
| evaluation of the palatability of chrysomelid larvae containing anthraquinones to birds. | chrysomelid larvae of the subfamily galerucinae, tribe galerucini, are known to contain 1,8-dihydroxylated 9,10-anthraquinones. since nonhydroxylated 9,10-anthraquinone is the active agent in several commercial products sold to protect seeds against birds, we suggested that the naturally occurring dihydroxylated anthraquinones of galerucine larvae may also act as protective devices against bird predation. tits (parus spp.) are potential predators of larvae of the tansy leaf beetle, galeruca tana ... | 1994 | 28306931 |