caa a22 4500 445389524 CHVBK 20180317143042.0 cr unu---uuuuu 170323e20110301xx s 000 0 eng 10.1007/s00049-010-0064-0 doi (NATIONALLICENCE)springer-10.1007/s00049-010-0064-0 Individual variation of ( S )-4-methyl-3-heptanone in heads of braconid wasp, Leiophron uniformis, and Pogonomyrmex ants indicates costs of semiochemical production [Elektronische Daten] [John Byers, Anat Levi-Zada] (S)-4-Methyl-3-heptanone is an alarm pheromone released from the mandibular glands in heads of harvester ants (Pogonomyrmex spp.). We used gas chromatography-mass spectrometry (GC-MS) to study the variation in amounts of this ketone among individual ants of a colony. P. barbatus contained about 2,000ng per head, while only about half of this amount was found in heads of P. rugosus and P. californicus. Individuals of P. barbatus from three different nests contained rather uniform amounts of the alarm pheromone within each colony (16-30% coefficient of variation CV; normal distributions skewed left), but one nest under food stress had a significantly lower mean amount. In contrast, both sexes of a small braconid wasp Leiophron uniformis, a parasitoid of Lygus plant bugs, contained up to 10ng of the same volatile enantiomer in their heads; and groups of either sex of the wasp exhibited normal distributions of quantities (64% CV, skewed right). The differences in the distributions between parasitoids and ants suggest that related members within a social ant colony may attempt to maintain a uniform level of ketone compared to independent variation in unrelated, solitary wasp individuals. When the wasp's leg was grasped with forceps, it tried to escape and bite the forceps as it ejected (S)-4-methyl-3-heptanone (detected by solid phase microextraction, SPME, and GC-MS). Since adult wasps are nonsocial and feed only on nectar, their sharp piercing mandibles in combination with this escape/biting behavior indicate the ketone is used for defense rather than for an alarm function as in harvester ants. Costs of producing the semiochemical in wasp L. uniformis and ants P. barbatus and P. californicus are suggested since populations exhibited a significant linear increase in the amount of (S)-4-methyl-3-heptanone with an increase in body weight of individuals. Springer Basel AG (outside the USA), 2010 Braconidae nationallicence Formicidae nationallicence Hymenoptera nationallicence Parasitoid nationallicence Alarm pheromone nationallicence Defensive secretion nationallicence Byers John USDA-ARS, Arid-Land Agricultural Research Center, 21881 North Cardon Lane, 85138, Maricopa, Arizona, USA aut Levi-Zada Anat Department of Entomology-Chemistry, Institute of Plant Protection, Agricultural Research Organization, POB 6, 50250, Bet Dagan, Israel aut Chemoecology SP Birkhäuser Verlag Basel 21/1(2011-03-01), 35-44 0937-7409 21:1<35 2011 21 49 https://doi.org/10.1007/s00049-010-0064-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00049-010-0064-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Byers John USDA-ARS, Arid-Land Agricultural Research Center, 21881 North Cardon Lane, 85138, Maricopa, Arizona, USA aut NATIONALLICENCE 700 1- Levi-Zada Anat Department of Entomology-Chemistry, Institute of Plant Protection, Agricultural Research Organization, POB 6, 50250, Bet Dagan, Israel aut NATIONALLICENCE 773 0- Chemoecology SP Birkhäuser Verlag Basel 21/1(2011-03-01), 35-44 0937-7409 21:1<35 2011 21 49 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer