Response ofMatsucoccus thunbergianae males to synthetic sex pheromone and its utilization for monitoring the spread of infestation
Attraction of (2E,4E,6R,10R)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one [1; (6R,10R)-matsuone] and its antipode [2; (6S,10S)-matsuone] toMatsucoccus thunbergianae males was studied in the laboratory and in the field. They showed stronger response to1. In laboratory bioassays, the threshold concentrations for male attraction with1 and2 were 16 fg and 150 pg, respectively. In the field, during the first two days after traps were set, traps baited with 50 µg of1 on rubber septa or filter paper rolls caught more males than control traps. Between the sixth day and the tenth day after traps were set, in a daily trap catch experiment, the traps with 50 µg of1 on filter paper rolls caught more males than control traps on one day only, whereas those on rubber septa were always effective. The shape of the traps did not affect male catches. Males were caught on pheromone traps in locations where no scales were found by the customary detecting procedures.
Specificity of the Sex Pheromones of Female Yellow Scales and California Red Scales
The sex pheromones of the female yellow scale, Aonidiella cilrina (Coquillett), and the California red scale, A. auranlii (Maskell), were bioassayed for cross attraction in the labmatory by exposing live females and extracts of females of each species on the rotating wheel olfactometer. In the field, live females were exposecd in ice cream carton traps. In all tests, the 2 pheromones were specific, based on the response of the males.
Synthesis of 2,4-Dimethyl-5-hexanolide, 2,4-Dimethyl-5-heptanolide and 2,4-Dimethyl-5-octanolide, the Lactones Identified in Volatiles from the Heads of the Male Black Garden Ant, Lasius niger
2,4-Dimethyl-5-hexanolide (1), 2,4-dimethyl-5-heptanolide (2), and 2,4-dimethyl-5-octanolide (3) are the volatile substances identified in the heads of the male black garden ant, Lasius niger. (2R,4R,5S)-Isomers of these lactones were synthesized by employing the iodolactonization reaction (5→4) as the key step.