Dominant bacteria associated with broods of mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae)

Richard S. Winder, Donna E. Macey, Joe Cortese


Mountain pine beetle (MPB) is the most damaging insect of mature pine forests in western North America. The current outbreak in British Columbia is the largest ever recorded. During a survey of beetle occurrence, well—established infestations were sampled in central B.C. and found to possess larval mortality. Bacteria or other microbes were among the potential causes of the mortality. Bacteria were isolated from living larvae and adults, as well as larval and adult beetle cadavers found in bark samples. Bacteria were identified by fatty acid methyl ester (FAME) analysis, which indicated 32 species of bacteria present in the MPB laivae. The predominant bacteria (Serratia liquefaciens, S. plymuthica) were detected in about a third of all sampled laivae, regardless of mortality. Rahnella aquatilis was found in 11% of all larvae examined and was usually (93%) associated with laival mortality. Interactions between two bluestaining fungal symbionts of the MPB (Grosmannia clavigera, Ophiostoma montium) and two of the isolated bacteria (S. liquefaciens and R. aquatilis) were assessed. S. liquefaciens and R. aquatilis both inhibited the growth of beetle-associated bluestain fungi by 72%. The bluestain fungi did not impede bacterial growth, and both bacteria grew on autoclaved bluestain mycelium. Combinations of the two bacterial species formed aggregates on practical-grade (crab) chitin, but there was no aggregation in pure cultures or on the autoclaved mycelium of G. clavigera or O. montium. These results indicated that the two bacteria may be capable of aggregation within the insects, and this may have implications for their combined effects in the beetle. The role of S. liquefaciens and R. aquatilis in MPB biology requires further investigation.


bark beetle; disease; larva; pathosystem

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Adams, A.S., D.L. Six, S.M. Adams and W.E. Holben. 2008. In vitro interactions between yeasts and bacteria and the fungal symbionts of the mountain pine beetle (Dendroctonus ponderosae). Microbial Ecology 56:460-466. DOI 10.1007/s00248-008-9364-0

Anonymous. 2002. Sherlock microbial identification system V. 4.5 operating manual. Midi Inc., Newark, DE, U.S.A.

Anonymous. 2005. Mountain pine beetle initiative: Interim report 2005. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoria, BC, Canada.

Barras, S.J. and T.J. Perry. 1975. Interrelationships among microorganisms, bark or ambrosia beetles, and woody host tissue: An annotated bibliography, 1965-1974. USDA Forest Service, Southem Forest Experiment Station, General technical report GTR-10.

Bellows, T.S., C. Meisenbacher and R.C. Reardon. 1998. Biological Control of Arthropod Forest Pests of the Western United States: A Review and Recommendations. USDA Forest Service, FHTET-96-21.

Berg, G., J . Frankowski and H. Bahl. 1999. Biocontrol of Verticillium wilt in oilseed rape by chitinolytic Serratia plymuthica. In: New horizons for an old crop: Proceedings of the 10”‘ International Rapeseed Congress, Canberra, Australia, 1999.

Berge, O, T. Heulin, W. Achouak, C. Richard, R Bally and J . Balandreau. 1991. Rahnella aquatilis, a nitrogen-fixing enteric bacterium associated with the rhizosphere of wheat and maize. Canadian Journal of Microbiology 37: 195-203.

Bleiker, K.P. and D.L. Six. 2007. Dietary benefits of fungal associates to an eruptive herbivore: Potential implications of multiple associates on host population dynamics. Environmental Entomology 36: 13841396.

Bleiker, K.P. and D.L. Six. 2009. Competition and coexistence in a multi-partner mutualism: Interactions between two fungal symbionts of the mountain pine beetle in beetle-attacked trees. Microbial Ecology 57: 191-202.

Brenner, D.J., H.E. Muller, A.G. Steigerwalt, A.M. Whitney, C.M. O’Hara and P. Kampfer. 1998. Two new Rahnella genomospecies that cannot be phenotypically differentiated from Rahnella aquatilis. International Journal of Systematic Bacteriology 48: 141-149.

Bushing, R.W. 1965. A synoptic list of the parasites of Scolytidae (Coleoptera) in North America north of Mexico. The Canadian Entomologist 97: 449-492.

Cardoza, Y.J., K.D. Klepzig and K.F. Raffa. 2006. Bacteria in oral secretions of an endophytic insect inhibit antagonistic fungi. Ecological Entomology 31: 636-645.

Caroff, N., C. Chamoux, F. Le Gallou, E. Espaze, F. Gavini, D. Gautreau, H. Richet and A. Reynaud. 1998. Two epidemiologically related cases of Rahnella aquatilis bacteremia. European Journal of Clinical Microbiology and Infectious Diseases 17: 349-3 52.

Dahlsten, D.L. 1982. Relationships between bark beetles and their natural enemies, pp. 140-182. In J .B. Mitton, and K.B. Sturgeon (eds.), Bark beetles in North American conifers: A system for the study of evolutionary biology. Univ. of Texas Press, Austin, Texas, USA.

Delalibera, I., Jr., J . Handelsman and K. Raffa. 2005. Contrasts in cellulolytic activities of gut microorganisms between the wood Borer, Saperda vestita (Coleoptera: Cerambycidae), and the bark Beetles, Ips pint and Dendroctonusfrontalis (Coleoptera: Curculionidae). Environmental Entomology 34: 541-547.

Hackstein, J .H.P. and C.L. Stumm. 1994. Methane production in terrestrial arthropods. Proceedings of the National Academy of Science 91: 5441-5445.

Hentzer, M. and M. Givskov. 2003. Pharmacological inhibition of quorum sensing for the treatment of chronic bacterial infections. Journal of Clinical Investigation 112: 1300-1307.

Heulin, T., O. Berge, P. Mavingui, L. Gouzou, K.P. Hebbar and J . Belandreau. 1994. Bacillus polymyxa and Rahnella aquatilis, the dominant N-2 fixing bacteria associated with wheat rhizosphere in French soils. European Journal of Soil Biology 30: 35-42.

Hofstetter, R.W., J.T. Cronin, K.D. Klepzig, J .C. Moser and M.P. Ayres. 2006. Antagonisms, mutualisms and commensalisms affect outbreak dynamics of the southern pine beetle. Oecologia 147: 679-691.

Horie, S., Y. Tanagida, K. Saheki, A. Hiraishi and K. Cho. 1985. Occurrence of Rahnella aquatilis psycrotrophic coliforms in mountain soils. Journal of the Food Hygienic Society of Japan 26: 573-578.

Hunt, D.W.A., J .H. Borden, J .E. Rahe and H.S. Whitney. 1984. Nutrient-mediated germination of Beauveria bassiana conidia on the integument of the bark beetle Dendroctonus ponderosae (Coleoptera: Scolytidae). Journal of Invertebrate Pathology 44: 304-314.

Joshi, S., M. Kozlowski, G. Selvaraj, V.N. Iyer and R.W. Davies. 1988. Cloning genes of the chitin utilization regulon of Serratia liquefaciens. Journal of Bacteriology 170: 2984-2988.

Kallioinen, A., A. Vaari, M. Ratto, J . Konn, M. Siika-aho and L. Viikari, 2003. Effects of bacterial treatments on wood extractives. Journal of Biotechnology 103: 67-76.

Kim, J.-J., E.A. Allen, L.M. Hrnnble, and C. Breuil. 2005. Ophiostomatoid and basidiomycetous fungi associated with green, red, and grey lodgepole pines after mountain pine beetle (Dendroctonus ponderosae) infestation. Canadian Journal of Forest Research 35: 274-284.

Laux, P., O. Baysal and W. Zeller. 2002. Biological control of fire blight by using Rahnella aquatilis Ra39 and Pseudomonas spec. R1. Acta Horticulturae 2002: 225-230.

Laux, P., J . Wesche and W. Zeller. 2003. Field experiments on biological control of fire blight by bacterial antagonists. Zeitschiift fuer Pflazenkrakheiten und Pflanzenschutz 110: 401-407.

Lebessi, E., I. Paraskaki, K. Grigoraki and H. Cosmidis. 1990. Rahnella aquatilis: saprophytic or opportunistic pathogen bacterium. Deltion Ellenikes Mikiiobiologikes Etaireias 35: 569-574.

Lee, R. Jr., J . Costanzo and M. Lee. 1998. Reducing cold-hardiness of insect pests using ice nucleating active microbes. Pages 97-130. In G. Hallman and D. Denlinger (eds.), Temperature sensitivity in insects and application in integrated pest management. Westview Press, Boulder, Co, USA.

Maraki, S., G. Samonis, E. Mamelakis and Y. Tselentis. 1994. Surgical wound infection caused by Rahnella aquatilis. Journal of Clinical Microbiology 32: 2706-2708.

Matsukura, H., K. Ktayama, N. Kitano, K. Kobayashi, C. Kanegane, A. Higuchi and S. Kyotani. 1996. Infective endocarditis caused by an unusual gram-negative rod, Rahnella aquatilis. Pediatric Cardiology 17: 108-1 1 1.

Moeck, H.A. and L. Safranyik. 1984. Assessment of predator and parasitoid control of bark beetles., Enviromnent Canada, Canadian Forestry Service, Pacific Forestry Centre, Victoria, British Columbia, Information report BC-X-248.

Moore, G.E. 1971. Mortality factors caused by pathogenic bacteria and fungi of the southern pine beetle in North Carolina. Journal of Invertebrate Pathology 17 : 28-37.

Moore, G.E. 1972a. Microflora from the alimentary tract of healthy southern pine beetles, Dendroctonus frontalis (Scolitidae), and their possible relationship to pathogenicity. Journal of Invertebrate Pathology 19: 72-75.

Moore, G.E. 1972b. Pathogenicity of ten strains of bacteria to larvae of the southern pine beetle. Journal of Invertebrate Pathology 20: 41-46.

Oh, H.M.L. and L. Tay. 1995. Bacteraemia caused by Rahnella aquatilis: Report of two cases and review. Scandinavian Journal of Infectious Disease 27: 79-80.

Pierson, E., D. Wood, J. Cannon, F. Blachere and L. Pierson III. 1998. Interpopulation signaling via N-acylhomoserine lactones among bacteria in the wheat rhizosphere. Molecular Plant Microbe Interactions 11: 1078-1084.

Pokhil, S. 1998. Biological properties of Rahnella aquatilis strains isolated in different regions. Mikrobiolohichnyi Zhurr1al 60: 31-37.

Safranyik, L. and Carrol, A. 2006. The biology and epidemiology of the mountain pine beetle in lodgepole pine forests. Pages 3-66 In L. Safranyik and W.R. Wilson, (eds.), The mountain pine beetle: a synthesis of biology, management, and impacts on lodgepole pine. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoria, British Columbia.

Scott, J .J ., D.C. Oh, M.C. Yuceer, J .C. Klepzig, J . Clardy and C.R. Currie. 2008. Bacterial protection of beetle-fungus mutualism. Science 322: 63.

Selenska-Pobell, S., E. Evguenieva-Hackenberg and O. Schwickerath. 1995. Random and repetitive primer amplified polymorphic DNA analysis of five soil and two clinical isolates of Rahnella aquatilis. Systematic and Applied Microbiology 18: 425-438

Six, D.L. and B.J. Bentz. 2007. Temperature determines symbiont abundance in a multipartite bark beetlefungus ectosymbiosis. Microbial Ecology 54:112-118.

Solheim, H. and P. Krokene. 1998. Growth and vinilence of mountain pine beetle associated blue-stain fungi, Ophiostoma clavigerum and Ophiostoma montium. Canadian Journal of Botany 76: 561-566.

Steidle, A., K. Sigl, R. Schuhegger, A. Ihring, M. Schrnid, S. Gantner, M. Stoffels, K. Riedel, M. Givskov, A. Hartmann, C. Langebartels and L. Eberl. 2001. Visualization of N-acylhomoserine lactone-mediated cell-cell communication between bacteria colonizing the tomato rhizosphere. Applied and Environmental Microbiology 67: 5761-5770.

Varbanets, L.D., A.N. Ostapchuk and N.V. Vinarskaya. 2004. Isolation and characterization of Rahnella aquatilis lipopolysaccharides. Mikrobiologichnii Zhurnal 66: 25-34.

Vasanthakumar, A., I. Delalibera Jr., J . Handelsman, K. Klepzig, P. Schloss and K. Raffa. 2006. Characterization of gut-associated bacteria in larvae and adults of the Southern Pine Beetle, Dendroctonusfrontalis Zimmerman. Enviromnental Entomology 35: 1710-1717.

Walton, A. 2009. Provincial-level projection of the current mountain pine beetle outbreak: Update of the infestation projection based on the 2008 Provincial Aerial Overview of Forest Health and revisions to the “Model” (BClV[PB.v6). B.C. Ministry of Forests and Range. Accessed on the intemet 31 August 2009: http://www .for. gov.bc .ca/hre/bcmpb/Yea16 .htm

Weyant, R.S., C.W. Moss, R.E. Weaver, D.G. Hollis, J.G. Jordan, E.C. Cook and M.I. Daneshvar. 1996. Bacterial identification by cellular fatty acids. Pages 565- 721. In R.S. Weyant (ed.), CDC's Identification of Unusual Pathogenic Gram-Negative Aerobic and Facultatively Anaerobic Bacteria. Williams and Wilkins, Baltimore, MD, USA.

Whitney, H.S. 1971.Association of Dendroctonus ponderosae (Coleoptera: Scolytidae) with blue stain fungi and yeasts during brood development in lodgepole pine. The Canadian Entomologist 303: 1496-1503.

Whitney, H.S. and S.H. Farris. 1970. Maxillary mycangium in the mountain pine beetle. Science 167: 54-55

Winder, R.S. and A.K. Watson. 1994. A potential microbial control for fireweed (Epilobium angusttfolium). Phytoprotection 75: 19-33.


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