Electroantennogram responses of synthetic periplanone-A and periplanone-B in the american cockroach
The electroantennogram responses of synthetic (−)-periplanone-B (PB) and (−)-periplanone-A (PA) were evaluated by using the antennae of the unmated male American cockroachPeriplaneta americana L. The threshold concentrations of the pheromone activities for the two chemicals were similar. Neither a synergistic nor an inhibitory response was noted, and only an additive effect was detected when PA and PB were applied as a mixture.
Isolation, identification, and synthesis of sex pheromone components of female tea cluster caterpillar,Andraca bipunctata walker (Lepidoptera: Bombycidae) in Taiwan
Octadecanal (18:Ald), (E)-11-octadecenal (E11–18:Ald), (E)-14-octadecenal (E14–18:Ald) and (E,E)-11,14-octadecadienal (E11,E14–18:Ald) were isolated and identified as major components from the pheromone glands of the tea cluster caterpillar,Andraca bipunctata, in Taiwan by analyzing the mass spectra of gland components and their DMDS adducts. GC retention times and mass spectra of the components were in agreement with those of authentic synthetic compounds. The average amount of 18:Ald,E11–18:Ald,E14–18:Ald andE11,E14–18:Ald per female gland (1 to 3 days old) was 121±76, 50±20, 187±75, and 237±110 ng, respectively, in a ratio of 20:8:31:41. SyntheticE11,E14–18:Ald caught more males than each of the other three components or blank control in field trapping tests.E11,E14–18:Ald is reported as an insect sex pheromone for the first time. Male antenna responded toE11,E14–18:Ald strongly in an EAG analysis. Furthermore, 4 hr after the injection of PBAN (pheromone biosynthetic activating neuropeptide) into decapitated female moths (2 days old), the percentage of theE11,E14–C18 Ald in the gland extract increased from 0% to 75.5%, which was also significantly more than that of unligated and uninjected control at 55.1%. All these data indicated thatE11,E14–18:Ald is the sex pheromone of theAndraca bipunctata in Taiwan.
A Sex Stimulant to the Male American Cockroach in the Compositae Plants
Following to the bioassay procedure," green leaves of several species of plants were tested and consequently we found Erigeron annus (L.) Pers., Eupatorium chinense L. var simplicifolium (Makino) Kitamura and Chry santhemum morifolium Ramat. were active amone them. Stalks and leaves of Erigeron annus (L.) Pers. were extracted with ethanol and hydrocarbon fraction was obtained after concentration and column chromatography over silica gel and 'Florisil.' The main peak of the hydrocarbon fraction on GLC (10% Carbowax 20M, 3mm•~75cm, 110°C) was revealed to be C15H24 by GC-MS [m/e 204