Tribolium species pheromones

The male-produced sex pheromone of the red flour beetle, Tribolium cas-taneum>has been identified to be (4 ,81 -4,8-dimethyldecanal 164 (tribolure) [320,321]. During bioassays, a mixture of the (4R,8R) and (4.R,8S)-stereoisomers proved to be more active than the pure (4 ,810-enantiomer [322]. The exact enantiomeric composition of the natural product remains as yet unknown. 4,8-Dimethyldecanal was found in other Tribolium species, too [323]. Factors affecting the pheromone production in T castaneum have been described by Hussain et al. [324]. 

The well known aldehyde, 4,8-dimethyldecanal, was shown to be a common pheromone of five Tribolium flour beetle species, 77 castaneum, 77 confusum, 77 freemani, and 77 madens. Two other volatiles were found 1 -pentadecene was shown to be a common semiochemical of flour beetles and 1,6-pentadecadiene was detected in five species, T.audax, 77 brevicomis, 77 destructor, T.freemani and 77 madens ... 

Male-produced aggregation pheromones are also present in the Tribolium spp. of flour beetles (reviewed in Plarre and Vanderwel, 1999). Many species use 4,8-dimethyldecanal ( tribolure ), and the role of other compounds remains to be clarified. Thebiosynthesisof 4,8-dimethyldecanal has not been investigated, although it is suspected to be of isoprenoid origin (Vanderwel and Oehlschlager, 1987). 

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