Neural and hormonal control of pheromone biosynthesis in the bark beetle, Ips paraconfusus

Outbreaks of conifer bark beetles in Europe and North America have increased in scale and severity in recent decades. In this study, we identify existing fossil records containing bark beetle remains from the end of the Last Glacial Maximum (~14,000 cal. yr BP) to present day using the online databases Neotoma and BugsCEP and literature searches, and compare these data with modern distribution data of selected tree-killing species. Modern-day observational data from the Global Biodiversity Information Facility (GBIF) database was used to map recorded distributions from AD 1750 to present day. A total of 53 fossil sites containing bark beetle remains, from both geological and archeological sites, were found during our searches. Fossil sites were fewer in Europe ( n = 21) than North America ( n = 32). In Europe, 29% of the samples in which remains were found were younger than 1000 cal. yr BP, while in North America, remains were mainly identified from late Glacial (~14,000–11,500 cal. yr BP) sites. In total, the fossil records contained only 8 of 20 species we consider important tree-killing bark beetles in Europe and North America based on their impacts during the last 100 years. In Europe, Ips sexdentatus was absent from the fossil record. In North America, Dendroctonus adjunctus, Dendroctonus frontalis, Dendroctonus jeffreyi, Dendroctonus pseudotsugae, Dryocoetes confusus, Ips calligraphus, Ips confusus, Ips grandicollis, Ips lecontei, Ips paraconfusus, and Scolytus ventralis were absent. Overall, preserved remains of tree-killing bark beetles are rare in the fossil record. However, by retrieving bulk material from new and existing sites and combining data from identified bark beetle remains with pollen, charcoal, tree rings, and geochemistry, the occurrence and dominance of bark beetles, their outbreaks, and other disturbance events can be reconstructed.

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The response of Dendroctonus valens and Temnochila chlorodia to Ips paraconfusus pheromone components and verbenone

The Canadian Entomologist ◽

10.4039/n06-013 ◽

2007 ◽

Vol 139 (1) ◽

pp. 141-145 ◽

Cited By ~ 9

Author(s):

Christopher J. Fettig ◽

Stephen R. McKelvey ◽

Christopher P. Dabney ◽

Roberty R. Borys

Keyword(s):

North America ◽

Bark Beetle ◽

Ips Paraconfusus ◽

Release Rates ◽

Dendroctonus Valens ◽

High Release ◽

Baited Traps ◽

Pheromone Components ◽

Temnochila Chlorodia ◽

Cut Stumps

AbstractThe red turpentine beetle, Dendroctonus valens LeConte, 1860 (Coleoptera: Curculionidae, Scolytinae), is a common bark beetle found throughout much of North America and China. In 2004, we observed that attack densities of the California fivespined ips, Ips paraconfusus Lanier, 1970 (Coleoptera: Curculionidae, Scolytinae), in logging debris were inversely related to D. valens attacks on freshly cut stumps, which led to the demonstration that components of the aggregation pheromone of I. paraconfusus inhibited the response of D. valens to attractant-baited traps. In this study, we test the response of D. valens and Temnochila chlorodia (Mannerheim, 1843) (Coleoptera: Trogositidae), a common bark beetle predator, to racemic ipsenol, racemic ipsdienol, and (−)-cis-verbenol (IPSR) in the presence and absence of two release rates of (−)-verbenone. The addition of a relatively low release rate of (−)-verbenone (4 mg/24 h) to attractant-baited traps did not affect catch and had no significant effect on the response of D. valens to IPSR. IPSR significantly reduced D. valens attraction to baited traps. The addition of high release rates of (−)-verbenone (50 mg/24 h) to IPSR significantly increased inhibition; however, the effect was not significantly different from that observed with (−)-verbenone alone (50 mg/24 h). Temnochila chlorodia was attracted to traps baited with (−)-β-pinene, (+)-3-carene, and (+)-α-pinene. The addition of (−)-verbenone (50 mg/24 h) significantly increased attraction. Traps baited with IPSR caught significantly more T. chlorodia than those baited with (−)-verbenone. Few other beetles were collected. We are hopeful that these results will help facilitate the development of an effective tool for protecting Pinus spp. from D. valens infestations.

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ENGRAVER BEETLES (SCOLYTIDAE: IPS SPECIES) AS VECTORS OF THE PITCH CANKER FUNGUS, FUSARIUM SUBGLUTINANS

The Canadian Entomologist ◽

10.4039/ent1231355-6 ◽

1991 ◽

Vol 123 (6) ◽

pp. 1355-1367 ◽

Cited By ~ 42

Author(s):

J.W. Fox ◽

D.L. Wood ◽

C.S. Koehler ◽

S.T. O’Keefe

Keyword(s):

Young Adults ◽

Bark Beetle ◽

Ips Paraconfusus ◽

Pitch Canker ◽

Santa Cruz ◽

Progeny Production ◽

Fusarium Subglutinans ◽

New Association

AbstractIps mexicanus (Hopkins) and I. paraconfusus Lanier can transmit a frugal pathogen that causes pitch canker [Fusarium subglutinans (Wollenw, and Reink.) Nelson, Toussoun, andMarasas], a disease recently identified in Monterey pines (Pirns radiata D. Don) in California. In Santa Cruz County, F. subglutinans was recovered from Ips spp. that emerged from pitch canker-in fee ted P. radiata and were captured in multiple-funnel traps baited with racemic Ips spp. pheromones. Ips paraconfusus adults experimentally contaminated with propagules of the fungus transmitted it to seedlings and mature pines. Field transmission was demonstrated when cankers were produced following pheromone-induced beetle attacks on pines. Ips spp. inoculated F. subglutinans into pine slash, thus creating reservoirs of this fungus. Larvae, pupae, and young adults acquired the fungus when their parents introduced it into logs. Ips spp. progeny production and development were not significantly altered by the fungus. In proximity to other bark beetle-associated fungi, growth of F. subglutinans was reduced and patchy. A new association may be developing among native Ips spp. and F. subglutinans.

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