A new C12 alcohol identified as a sex pheromone an a trail-following pheromone in termites: the diene (Z,Z)-dodeca-3,6-dien-1-ol

20 ref. DOI:10.1007/s00114-003-0481-9International audienc

Species specificity of trail pheromones of fungus-growing termites from northern Vietnam

International audienc

Species specificity of trail pheromones of fungus-growing termites from northern Vietnam

International audienc

(Z)-dodec-3-en-1-ol, a novel termite trail pheromone identified after solid phase microextraction form Macrotermes annandalei

International audienc

Ultrastructure of posterior sternal glands of Macrotermes annandalei (Silvestri): new members of the sexual glandular set found in termites (Insecta)

0362-2525 (Print) Comparative Study Journal ArticleIn female alates of Macrotermes annandalei, two types of abdominal glands are involved in the secretion of sex pheromone. Tergal glands are found at the anterior margin of tergites 6-10 and posterior sternal glands (PSGs) are located at the anterior margin of sternites 6-7. The cytological features of both types of glands are quite similar. The fine structural organization of PSGs is studied more precisely and described for the first time. The glandular cuticle is pitted with narrow apertures corresponding to the openings of numerous subcuticular pouches. Several Class 3 glandular units open in each pouch. One canal cell and one secretory cell make an individual glandular unit. The canal cell is enlarged apically and is connected with the other canal cells to form a common pouch. Based on the structural features found in these glands, we propose a common secretory process for PSGs and tergal glands. During the physiological maturation of alates inside the nest, secretory vesicles amass in the cytoplasm of secretory cells, while large intercellular spaces collapse the cuticular pouches. At the time of dispersal flight, pouches are filled with the content of secretory vesicles while intercellular spaces are sharply reduced. After calling behavior, no secretion remains in the glands and pouches collapse again, while secretory cells are drastically reduced in size. The structure and the secretory processes of PSGs and tergal glands are compared to those of abdominal sexual glands known in termites

Research on sexual behaviour of some tephritid fruit flies in Reunion island

Depuis 1994, l'étude du comportement sexuel des Tephritidae au CIRAD-FLHOR Réunion s'est focalisée sur Ceratitis sp.. L'impact des phéromones, le rythme circadien et d'autres facteurs pouvant influer l'attraction sexuelle et les comportements de reproduction et de ponte ont été également étudiés. Le comportement sexuel est identique chez les mâles de C. rosa et C. capitata au laboratoire. En revanche, le rythme circadien est différent. Le comportement sexuel et l'attraction des femelles s'observent 10 jours après l'émergence des mâles. La synthèse et l'efficacité des phéromones d'attraction dépendent du régime alimentaire. Les observations faites sur Dacus spp. et Trirhithromya cyanescens confirment l'influence du rythme circadien, de l'âge et de l'alimentation sur le comportement sexue

A new C12 alcohol identified as a sex pheromone and a trail-following pheromone in termites: the diene (Z,Z)-dodeca-3,6-dien-1-ol

0028-1042 (Print) Journal ArticleThe diunsaturated C12 alcohol (Z,Z)-dodeca-3,6-dien-1-ol (dodecadienol) has been characterized by GC-MS and FTIR as a novel releaser pheromone in termites. This alcohol identified in Ancistrotermes pakistanicus (Termitidae, Macrotermitinae) possesses a double pheromonal function which again illustrates the chemical parsimony of termites compared with other social insects. In workers, dodecadienol elicits trail-following at a very low concentration (activity threshold at 0.1 pg/cm of trail); in male alates it induces trail-following at a low concentration (1-10 pg/cm) and sexual attraction at a higher concentration (about 1 ng). Traces of the monounsaturated C12 alcohol (Z)-dodec-3-en-1-ol (dodecenol), known as a trail pheromone of several Macrotermitinae, were also found in the sternal gland extracts of A. pakistanicus, although only dodecadienol was present at the surface of the sternal gland. Workers of A. pakistanicus are not sensitive to dodecenol, but they are as sensitive to dodecatrienol as to dodecadienol. However, in the study area (Vietnam), A. pakistanicus is living in sympatry only with those Macrotermitinae using dodecenol as a trail pheromone, the foraging populations therefore being well isolated through their respective trail pheromones. The presence of three types of unsaturated C12 alcohols as releaser pheromones in the only Macrotermitinae subfamily is discussed, and a possible biosynthetic pathway from linoleic acid is proposed for dodecadienol

(Z)-dodec-3-en-1-ol, a novel termite trail pheromone identified after solid phase microextraction from Macrotermes annandalei

0022-1910 (Print) Journal Article(Z)-dodec-3-en-1-ol was isolated and identified by GC-MS as the major component of the trail-following pheromone from whole body and sternal gland extracts of workers of the fungus-growing termite, Macrotermes annandalei (Silvestri) (Termitidae, Macrotermitinae). For the first time, this trail pheromone was also identified by using solid phase microextraction from the surface of the secretory sternal gland of workers. Bioassays showed that synthetic dodecenol induced both orientation and recruitment behavioral effects. The activity threshold of (Z)-dodec-3-en-1-ol in eliciting trail-following is similar to that of (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol in the Rhinotermitidae, but amounts of dodecenol secreted are 100 times higher than those of dodecatrienol. There is about 1 ng of (Z)-dodec-3-en-1-ol per worker. Artificial trails made of synthetic dodecenol are able to compete with natural trails in the field. The activity duration of synthetic (Z)-dodec-3-en-1-ol trails is shorter than that of trails made from whole sternal secretion of workers. Observations showed that (Z)-dodec-3-en-1-ol is probably the only major component of the trail-following pheromone of M. annandalei and that it could be associated with other compounds in a pheromonal blend providing specificity and/or stability to trails