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The red turpentine beetle, Dendroctonus valens LeConte (Coleoptera: Curculionidae: Scolytinae), is one of the most destructive invasive forest pests in China. Little is known about the biological characteristics of red turpentine beetle. Analysis of the frequency distribution has shown that red turpentine beetle's larvae have five instars with head capsule width 0.64, 0.83, 1.16, 1.45, and 1.99 mm, respectively. The ratio of increase of head capsule width is 1.33, which is consistent with Dyar's rule. The duration of egg, larval, and pupal is ≈10, 84, and 10 d, respectively. After its emergence, the callow adult darkens to the typical reddish brown by the time it is ready to leave the tree; beetles begin to “fly out” at the 10th day and continue for 20 d, with the peak flight taking place on the 21st day. Pairs of red turpentine beetles introduced into pine bolts produced 106 offspring. Such basic information is important for developing management strategies to combat this invasive bark beetle in China. [ABSTRACT FROM PUBLISHER]

The red turpentine beetle, Dendroctonus valens LeConte, is one of the most destructive invasive forest pests in China, having killed more than 6 million pines since its first outbreak in 1999. Little is known about D. valens pheromone biology and no aggregation pheromone has yet been identified. Analysis by gas chromatograph/mass spectrometer of volatiles collected from live beetles in China showed that female beetles produce frontalin and males do not. Olfactory assays in the laboratory showed that males were attracted to frontalin at a wide range of concentrations, whereas females were attracted to it at a narrow range of concentrations. In field trials, 3-carene, a monoterpene kairomone from a pine tree selected to host the beetles attracted both sexes, and when frontalin was added, the total number of beetles captured increased by almost 200%. However, increasing concentrations of frontalin significantly decreased the percentage of female beetles trapped. These results suggest a new role of frontalin as an aggregation pheromone in addition to a female-produced sex pheromone, which was previously shown in a North American population. The dual functions of the pheromone frontalin produced by D. valens females, as well as its ecological significance for overcoming host resistance, are discussed. [ABSTRACT FROM AUTHOR]