Pheromone concentration

Coureaud, G., Langlois, D., Sicard, G. and Schaal, B. (2004) Newborn rabbit reactivity to the mammary pheromone Concentration-response relationship. Chem. Senses 29, 341-350. 

Mating disruption involves the use of artificially produced high pheromone concentrations in a confined area to impede the ability of males to... 

Elkinton, J. S., Card6, R. T., and Mason, C. J. (1984). Evaluation of time-average dispersion models for estimating pheromone concentrations in a deciduous forest. Journal of Chemical Ecology 10,1081-1108. 

Mating disruption experiments with spruce budworm in laboratory, small-scale field tests and "semi-operational" field trials have recently been reviewed (27). Work to date, on the disruption of spruce budworm mating behavior has concentrated on the use of the primary components /Zll-14 Ald s (95-97% E), and the results indicate that some mating disruption does occur. There appears to be a positive correlation between the applied pheromone concentration and the percent disruption, and based on field cage studies, percent disruption is inversely related to insect density (27) as would be predicted (32). 

In this paper, I will describe results obtained in the continuation of this work with the laminate formulations. The laminates consist of an Inner layer that contains the pheromone plus laminating resins and outer layers made of polymeric membranes. The lure diffuses from the inner reservoir through the membrane layers and evaporates from the polymer surface. At the pheromone concentrations that we have evaluated, the release rate generally follows first order kinetics, with the rate proportional to the concentration of lure. The parameters of the polymeric membrane, including thickness and backbone... 

A key feature of the Hereon dispensing system is the ease of regulating the pheromone emission rate from the dispenser. Thus, the emission rate may be adjusted by varying one or more of a variety of parameters (4) 1) thickness of outer layers of the dispensers, 2) pheromone concentration per unit area of the dispenser, 3) size (area) of the dispenser, 4) amount of flake applied per acre, 5) the polymer used to fabricate the dispenser, and/or 6) polymer stiffness. Duration of effectiveness may also be extended by increasing the thickness of the inner layer of the dispenser, in effect increasing the size of the pheromone reservoir of each flake. 

The measurement of pheromone concentrations in the atmosphere was first described by Caro t al. for disparlure (11). 

Figure 7. Midday pheromone concentrations and temperatures at mid-canopy following aerial application of formulation A (500 g a.i./ha).

Disription Treatment Pheromone Concentration in Trap-baits (%) Average Males Captured/Trapi./... 

Figure 6. Effect of Resin 0il Ratio for Equivalent Pheromone Concentration (750 ppm)...

A. Mafra-Neto and R.T. Carde, Influence of plume structure and pheromone concentration on upwind flight of caudra cautella males. Physiol. Entomol. 20 (1995) 117-133. 

While pheromones are known to mediate a variety of behaviours in other mammals, the human vomeronasal organ (VNO), which conveys information about pheromone concentration to the brain, was believed to be absent or atrophied in adults. It was also believed to lack any... 

Charlton, R.E., Kanno, H., Collins, R.D. Carde, R.T. 1993. Influence of pheromone concentration and ambient temperature on flight of the gypsy moth, Lymantria dispar (L.), in a sustained-flight wind tunnel. Physiol. Entomol. 18 349—362. 

All species of teleost fish examined to date have been found to use sex pheromones (Liley 1982 Liley Stacey 1983 Stacey, Kyle Liley 1986 Stacey, Cardwell, Liley, Scott Sorensen 1994). Further, where examined (about a dozen species Sorensen Stacey, this volume), these cues have been found to be derived from sex hormones. However, the temporal nature of pheromone release has yet to be characterized. Temporal characteristics of pheromone release (i.e. pulse frequency and duration and interpulse interval) might be important for two reasons (Dusenbery 1989). First, intermittent release of pheromone could produce temporal and spatial variations in pheromone concentration that might prevent or reduce sensory adaptation. Second, the temporal characteristics of pheromone release may provide information about the proximity and identity of the signal s sender. 

Androgen-dependent urine esterases produced in both kidney and sex-accessory organs (Shaw and Koen, 1963 McPartland et al., 1981) of male rodents may be associated with these pheromones. Like pheromones, concentrations of urine esterases vary among mouse strains (McPartland et al., 1981). Esterases are less concentrated in urine from subordinated Swiss albino males than from their dominant counterparts (Labov, 1979). 

A mathematical model for the transmission of a chemical signal has been developed by Bossert and Wilson (2). According to this model, the substance is transmitted through the air in accordance with simple laws of diffusion when the air is still and the substance cannot adsorb on or react with other substances. At any point away from the emitter, pheromone concentration is a function of 1) the rate of molecular emission, 2) the diffusion coefficient of the substance, 3) the distance from the source and 4) the time from the initiation of the emission. 

Bossert and Wilson (1%3) were the first to use diffusion equations to estimate pheromone concentrations and active space dimensions in still air. They derived equations for three still air situations (i) an instantaneous puff, (ii) a point source emitting at a continuous rate, and (iii) a moving point source such as an ant depositing a trail pheromone. For an instantaneous puff on the reflecting plane surface, such as an ant releasing a momentary burst of alarm pheromone, the active space is a half sphere with a radius (R) at (t) seconds after release of the puff given by ... 

Baker, T. C. and Roelofs, W. L. (1981) Initiation and termination of Oriental fruit moth male response to pheromone concentration in the field. Env, Ent., 10, 211-18. 

Hagaman, T. E. and Carde, R. T. (1983) Effect of pheromone concentration on the organization of pre-flight behaviors of the male gypsy moth, Lymantria dispar (L.). /. Chem. Ecol. (in press). 

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