title: Juvenile hormone III titers and regulation of soldier caste in coptotermes formosanus (Isoptera: Rhinotermitidae).
abstract: Juvenile hormone (JH) is an important growth hormone in insects that has also been implicated in caste determination in termites. Gas chromatography-mass spectrometry was used to establish that the JH in the Formosan subterranean termite, Coptotermes formosanus Shiraki, is JH III. JH III titers were measured in workers, pre-soldiers, and soldiers from samples collected from the field. The average titers of JH III in workers and soldiers were about 13 and 25 pg mg(-1), respectively. However, pre-soldiers contained a significantly higher amount, 596 pg mg(-1). As expected, treatment of workers with a JH-analogue, methoprene, triggered rapid formation of pre-soldiers. However, these pre-soldiers had a very low JH III titer (62 pg mg(-1)). It appears that the application of JHA, while inducing pre-soldier formation, does not increase the endogenous JH III titer. The titer, however, increased as the pre-soldiers aged and before transforming into soldiers.
authors.affiliation: Formosan Subterranean Termite Research Unit, Agricultural Research Service, USDA, SRRC, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA. ypark@srrc.ars.usda.gov
authors.forename: Yong Ihl
authors.initials: YI
authors.lastname: Park
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Raina
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D005260:Female; D020049:Isoptera / Q000254:growth & development / Q000502:physiology*; D007605:Juvenile Hormones / Q000378:metabolism*; D008297:Male; D010641:Phenotype; D011157:Population Dynamics; D012717:Sesquiterpenes / Q000378:metabolism*; D012919:Social Behavior
chemical_list: D007605:Juvenile Hormones; D012717:Sesquiterpenes; C036585:juvenile hormone III