Search results for " pheromone"

Medicinal alkaloid as a sex pheromone

1997

Synthesis of the aggregation pheromone of the Colorado potato beetle from its degradation product

2015

Incubation of the Colorado potato beetle aggregation pheromone, (S)-1,3-dihydroxy-3,7-dimethyl-6-octen-2-one, with antennal or leg extracts from this beetle gave 6-methyl-5-hepten-2-one as the major product. This ketone was used as a substrate in a stereoselective synthesis of the pheromone. It was attached to the butanediacetal of glycolic acid with good stereoselectivity and the desired isomer was further enriched by purification of the product of this reaction on silica gel.

Sex pheromones are not always attractive: changes induced by learning and illness in mice

2014

A male-specific major urinary protein named darcin is attractive to female mice, Mus musculus, stimulates a learned attraction to volatile components of a male's urinary odour and induces spatial learning. In this article we show that darcin also induces learned attraction for a previously neutral olfactory stimulus (the odorant isoamyl acetate), acquired by repeated presentation of both stimuli together. We hypothesize that this is a case of olfactory–vomeronasal associative learning, in which darcin acts as the unconditioned reinforcer. However, the presence of darcin is not always attractive to adult female mice. Urine from males parasitized by the nematode Aspiculuris tetraptera has no …

Attractive properties of sexual pheromones in mice

2002

Abstract It is generally assumed that chemical signals (sexual pheromones) constitute the primary stimulus for sexual attraction in many mammals. However, it is unclear whether these pheromones are volatile or nonvolatile and which sensory systems are involved in their detection (vomeronasal and/or olfactory). Moreover, it has been demonstrated that experience influences the behavioral response to sexual pheromones and the sensory systems implicated. In order to clarify this issue, the attractive properties of volatile and nonvolatile components of the male-soiled bedding have been analyzed in female mice that had no previous experience with adult male-derived chemical signals (chemically n…

Pheromonal emission during the mating behavior ofEurycotis floridana (Walker) (Dictyoptera: Blattidae)

1996

The sexual behavior of males and females ofEurycotis floridana was investigated and the various associated behavioral sequences are described. Olfactometer data proved that the male produces a volatile sex pheromone attractive at a distance to conspecific females. The male initiates courtship behavior by exposing the glandular areas on the anterior parts of abdominal tergites 2, 7, and 8. This male calling behavior was observed throughout the day. The males can mate when 8 days old, whereas virgin females are sexually receptive 18 days after becoming adults. Once attracted near the male, the female opens her genital atrium and climbs on the back of the male, where she feeds on the glandular…

The chemistry of competition: exploitation of heterospecific cues depends on the dominance rank in the community

2014

Interspecific competition is an important ecological mechanism shaping the traits of the interacting species and structuring their communities. Less competitive species benefit from evading direct encounters with aggressive dominants, whereas dominant species could use cues left by subordinates to steal their resources or to chase them off. Here, we studied competitive interactions among five common and syntopic ant species in Central Europe (Formica polyctena, Formica rufibarbis, Lasius niger, Myrmica rubra and Tetramorium caespitum) and investigated their ability to react to heterospecific chemical cues. Using aggression assays, we established a clear dominance hierarchy of these species,…

2015

Insects encounter a vast repertoire of chemicals in their natural environment, which can signal positive stimuli like the presence of a food source, a potential mate, or a suitable oviposition site as well as negative stimuli such as competitors, predators, or toxic substances reflecting danger. The presence of specialized chemoreceptors like taste and olfactory receptors allow animals to detect chemicals at short and long distances and accordingly, trigger proper behaviors towards these stimuli. Since the first description of olfactory and taste receptors in Drosophila fifteen years ago, our knowledge on the identity, properties, and function of specific chemoreceptors has increased expone…

Caste-dependent reactions to soldier defensive secretion and chiral alarm/recruitment pheromone inNasutitermes princeps

1990

The soldier frontal gland secretion ofNasutitermes princeps induces strong short-range caste-specific alarm and attraction in both soldiers and workers. Soldiers are excited and patrol the surroundings of the source. The secretion per se does not induce ejection of additional secretion. Large workers of the second stage or older are massively attracted when tested in homogeneous groups. They focus their activities much more accurately than the soldiers around the source. The workers' reaction is less intense in the presence of soldiers. Large and small workers of stage 1 scarcely react at all to the secretion, whether tested in homogeneous or mixed groups. These results suggest the followin…

Caste differentiation in Isoptera: basic features, role of pheromones

1991

The polymorphism of termites, essentially phenotypic, results from alternative orientations during individual development, triggered by hormones and neurohormones. The hormonal equilibrium is itself modulated by several influences, both from the outer world and the society. Among the latter, the primer pheromones seem especially important in the regulation (either by stimulation or inhibition) of the separate castes.

Beetles (Coleoptera) caught with pheromones of Gnathotrichus retusus and G. sulcatus (Col., Scolytidae) in southern Finland

2001

The ambrosia beetle Gnathotrichus materiarius, which originally came from North America, was discovered in southern Finland in 1996. In 1997, using Norwegian drainpipe traps baited with pheromones of Gnathotrichus retusus and G. sulcatus, we collected beetles in the region where the first specimen had been caught in order to determine whether this potential pest species had become established in the area. Samples from a total of 16 traps included 79 species of beetles and 719 individuals, but no specimens of G. materiarius. The most abundant species in the samples were the ambrosia beetles Xyleborus dispar and Trypodendron lineatum. Several predators and other associates of bark beetles wer…