PHEROMONE CHIRALITY OF AFRICAN PALM WEEVIL, Rhynchophorus phoenicis (F.) AND PALMETTO WEEVIL, Rhynchophorus cruentatus (F.) (COLEOPTERA: CURCULIONIDAE)

Article abstract of DOI:10.1007/BF02036199

There are four stereoisomers of both 3-methyl-octan-4-ol, the aggregation pheromone of the African palm weevil, Rhynchophorus phoenicis (F.) and 5-methyl-octan-4-ol, the aggregation pheromone of the palmetto weevil, Rhynchophorus cruentatus (F.). Synthetic stereoisomers of 3-methyl-octan-3-ol and 5-methyl-octan-4-ol were baseline-separated on a Cyclodex-B fused silica column. Use of this column in gas chromatographic-electroantennographic detection (GC-EAD) and GC-mass spectrometric (GC-MS) analyses revealed that only one stereoisomer, (3S,4S)-3-methyl-octan-4-ol and (4S,5S)-5-methyl-octan-4-ol, is produced by male R. phoenicis and male R. cruentatus, respectively, and elicits good antennal responses by conspecific male and female weevils. In field trapping experiments, with R. phoenicis in Cote d'Ivoire and R. cruentatus in Florida, (3S,4S)-3-methyl-octan-4-ol and (4S,5S)-5-methyl-octan-4-ol strongly enhanced attraction of fresh palm tissue, whereas other stereoisomers were behaviorally benign. Stereoisomeric 3-methyl-octan-4-ol and 5-methyl-octan-4-ol may be utilized to monitor and/or manage populations of these two palm weevils. - Keywords: Coleoptera, Curculionidae, Rhynchophorus phoenicis, Rhynchophorus cruentatus, aggregation pheromone, pheromone chirality, (3S,4S)-3-methyl-octan-4-ol, (3R,4R)-3-methyl-octan-4-ol, (3S,4R)-3-methyl-octan-4-ol, (3R,4S)-3-methyl-octan-4-ol, (4S,5S)-5-methyl-octan-4-ol, (4R,5R)-5-methyl-octan-4-ol, (4S,5R)-5-methyl-octan-4-ol, (4R,5S)-5-methyl-octan-4-ol