title: Infrared thermography and odour composition of the Amorphophallus gigas (Araceae) inflorescence: the cooling effect of the odorous liquid.
abstract: During the second blooming of a cultivated Amorphophallus gigas Teijsm and Binnend in the Botanical Gardens of the University of Tokyo, the surface temperature of the inflorescence was measured using an infrared camera. Contrary to studies of other species in the genus Amorphophallus, the surface of the inflorescence showed only very faint thermogenesis and had a lower temperature than that of the background. This cooling effect appeared to be due to a loss of heat through evaporation, which was caused by the secretion of a very large amount of odorous liquid. Chemical analysis revealed that the major components of this liquid were acetic acid, propionic acid, butyric acid and valeric acids. The composition of the odorous liquid was slightly different between the spathe surface and the sterile appendix. The major component(s) of the odorous material from the spathe was butyric acid, and from the sterile appendix was valeric acids. These components would play dual roles of adding the characteristic smell to the inflorescence and cooling the inflorescence.
authors.affiliation: Botanical Gardens, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kakishima
authors.forename: Y
authors.initials: Y
authors.lastname: Terajima
authors.forename: J
authors.initials: J
authors.lastname: Murata
authors.forename: H
authors.initials: H
authors.lastname: Tsukaya
mesh_terms: D019342:Acetic Acid / Q000032:analysis; D029064:Araceae / Q000737:chemistry*; D020148:Butyric Acid / Q000032:analysis; D056626:Inflorescence / Q000737:chemistry; D007259:Infrared Rays; D009812:Odorants / Q000032:analysis*; D010421:Pentanoic Acids / Q000032:analysis; D011422:Propionates / Q000032:analysis; D013696:Temperature; D013817:Thermography
chemical_list: D010421:Pentanoic Acids; D011422:Propionates; D020148:Butyric Acid; C038780:n-pentanoic acid; C029658:propionic acid; D019342:Acetic Acid