Activity of male pheromone of Melanesian rhinoceros beetle Scapanes australis.
Laboratory and field investigations were carried out to investigate the nature and role of the male pheromone emitted by the Dynast beetle Scapanes australis and to develop a mass trapping technique against this major coconut pest in Papua New Guinea. We report the biological data obtained from natural and synthetic pheromone, previously described as an 84:12:4 (w/w) mixture of 2-butanol (1), 3-hydoxy-2-butanone (2), and 2,3-butanediol (3). EAG recordings from natural and synthetic pheromone and a pitfall olfactometer were poorly informative. In contrast, extensive field trapping trials with various synthetic pheromone mixtures and doses showed that 1 and 2 (formulated in polyethylene sachets in 90:5 v/v ratio) were necessary and sufficient for optimum long-range attraction. Beetles were captured in traps baited with racemic 1 plus 2, with or without a stereoisomer mixture of 3 (2.5- to 2500-mg/day doses). Plant pieces, either sugarcane or coconut, enhanced captures by the synthetic pheromone, which was active alone. Traps with the pheromone caught both sexes in a 3:2 female-male ratio. A pheromone-based mass trapping led to the capture of 2173 beetles in 14 traps surrounding 40 ha of a cocoa-coconut plantation. The captures followed a log-linear decrease during the 125-week trapping program. The role of the male pheromone and its potential for crop protection are discussed.
Rochat
Didier
D
INRA, Unité de Phytopharmacie et Médiateurs Chimiques, Centre de Versailles, France. rochatd@versailles.inra.fr
Morin
Jean-Paul
JP
Kakul
Titus
T
Beaudoin-Ollivier
Laurence
L
Prior
Robert
R
Renou
Michel
M
Malosse
Isabelle
I
Stathers
Tanya
T
Embupa
Sebastian
S
Laup
Samson
S
D000818:Animals; D000440:Butanols / Q000494:pharmacology*; D002074:Butanones / Q000494:pharmacology*; D002072:Butylene Glycols / Q000494:pharmacology*; D003059:Cocos; D001517:Coleoptera / Q000502:physiology*; D005260:Female; D007300:Insect Control; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology; D012724:Sex Attractants / Q000494:pharmacology*; D012903:Smell
D000440:Butanols; D002074:Butanones; D002072:Butylene Glycols; D010936:Plant Extracts; D012724:Sex Attractants; C043958:2-butanol; C026978:2,3-butylene glycol