Pheromone glands volatile pheromones

All life stages of the German cockroach produce 3,11-dimethylnonacosane, suggesting that production of a sex-specific contact pheromone may be less dependent on differentiation of sexually dimorphic pheromone glands, as is the case for volatile pheromones, and more so on the endocrine milieu of the adult female. Normally, adult male cockroaches produce much less JH III than do females, and males have a much lower titer of JH III in the hemolymph (Piulachs et al., 1992 reviewed in Tobe and Stay, 1985 Wyatt and Davey, 1996). However, when newly emerged males were exposed to filter papers treated with the JH mimic hydroprene they exhibited a six-fold elevation in female pheromone on their cuticle (Schal, 1988). Although substantial, this limited stimulation indicates... 

Little is known of the cellular processes that deliver volatile pheromones from secretory cells to the cuticular surface, even in the intensively researched Lepidoptera. Based on results from ultrastructural studies of the moth Heliothis virescens, Raina el al. (2000) recently speculated that secretory cells of the pheromone gland somehow deliver pheromone or its precursors to hollow cuticular hairs. During calling behavior the female exposes the gland and also the cuticular hairs that exude pheromone droplets. Raina et al. (2000) further posit that as the female retracts the ovipositor more pheromone is squeezed onto the exposed surface, thus recharging the cuticular hairs. 

Viridifloric /3-lactone, 143, has been identified as one of the pheromone components of a complex mixture of volatiles released by the pheromone glands of the male Idea leuconoe butterfly during courtship <1996BMC341>. A racemic mixture of both diastereoisomers was synthesized in four steps from the dilithio salt of 3-methylbutyric acid 144 alkylation with ethanal, dehydration of the secondary alcohol with phosphorus pentoxide, dihydroxylation of the C-C double bond with osmium tetraoxide, and finally formation of the /3-lactone by cyclization with sulfonyl chloride. By comparison with the sample isolated from I. leuconoe, the absolute configuration was established to be (2V,3V)-2-hydroxy-2-(l-methylethyl)-3-butanolide 143. 

Analysis of the volatile pheromone collected from calling female H. virescens is not yet complete. However, preliminary results indicate that 14 A1 and Z9-14 A1 are emitted in greater quantities, relative to Zll-16 A1, than are present in the gland. Thus our data suggest that the true emitted pheromone of H. virescens females may consist predominantly of 14 A1, Z9-14 A1, 16 A1, and Z11-16 A1. 

Figure 10. Male H. virescens behavioral sequences evoked by calling females, volatiles collected from two females calling for 3 h, and one female equivalent extracts of each pheromone gland and of the whole ovipositor. Numbers in circles indicate probability of a transition occurring.

Mauchamp, B. and Grandperrin, D. (1982). Chromatographie en phase gazeuse des composes volatils des glandes h pheromones des abeilles Methodes d analyse directe. Apidologie 13, 29-31. 

The first insect pheromone to be isolated and characterized was bombykol (structure 72) from the silk moth, Bom-byx mori, by Butenandt and co-workers (Kelly, 1990), Pheromone glands (500,000) were extracted to yield 12 mg of the 4 -nitroazobenzene-4-carboxylic acid ester of the volatile alcohol. As few as 2500 molecules of the pheromone is enough to elicit behavior in the male moth (Hecker and Butenandt, 1984 Kelly, 1990). 

PAs of the lycopsamine type (Fig. 11) [96]. The behavior-modifying function of PA-derived male pheromones has so far only been established in a few cases (see Sect. 4.1.1). Male pheromone glands often contain complex mixtures of chemically diverse volatiles. The chemistry and behavioral biology of PA-derived pheromones produced in the androconial organs are discussed in detail in a number of excellent reviews [10,11,75,96,99]. 

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