@article {9417,
	title = {Transport of fungal symbionts by mountain pine beetles},
	journal = {Canadian Entomologist},
	volume = {141},
	number = {5},
	year = {2009},
	month = {September-Octobe},
	pages = {503-514},
	abstract = {The perpetuation of symbiotic associations between bark beetles (Coleoptera: Curculionidae: Scolytinae) and ophiostomatoid fungi requires the consistent transport of fungi by successive beetle generations to new host trees. We used scanning electron microscopy and culture methods to investigate fungal transport by the mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins. MPB transports its two main fungal associates, Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingfield and Ophiostoma montium (Rumbold) von Arx, in sac-like mycangia on the maxillary cardines as well as on the exoskeleton. Although spores of both species of fungi were observed oil MPB exoskeletons, often in pits, O. montium spores were generally more abundant than G. clavigera spores. However, a general scarcity of spores of either species on MPB exoskeletons compared with numbers on scolytines that lack sac-like mycangia indicates that fungal transport exteriorly on MPBs is incidental rather than adaptive. Conidia were the dominant spore type transported regardless of location or species; however, Our results Suggest that once acquired in mycangia, conidia may reproduce in a yeast-like form and even produce hypha-like strands and compact conidiophore-like structures. Fungi that propagate in mycangia may provide beetles with a continual source of inocula during the extended egg-laying period.},
	keywords = {Dendroctonus ponderosae},
	isbn = {0008-347X},
	author = {Bleiker, K. P. and Potter, S. E. and Lauzon, C. R. and Six, D.L.}
}
@article {9418,
	title = {Dietary benefits of fungal associates to an eruptive herbivore: potential implications of multiple associates on host population dynamics},
	journal = {Environmental Entomology},
	volume = {36},
	number = {6},
	year = {2007},
	month = {December},
	pages = {1384-1396},
	abstract = {We used the mountain pine beetle (Dendroctonus ponderosae Hopkins) and its two fungal associates, Grosmannia clavigera and Ophiostoma montium, to study potential nutritional benefits of fungi to bark beetles. We tested for potential effects of feeding on phloem colonized by fungi on beetle performance in field and laboratory studies. The fungi increased nitrogen levels in the phloem of attacked trees by 40\%, indicating that it may be an important source of dietary nitrogen for mountain pine beetles. However, nitrogen levels of phloem inoculated with fungi in the laboratory were similar to uncolonized phloem, indicating that the fungi may redistribute nitrogen from the sapwood to the phloem rather than increase absolute levels of nitrogen. Beetles emerging from attacked trees carrying G. clavigera were larger than beetles carrying O. montium, which in turn were larger than beetles lacking fungi. Results of experimental laboratory studies varied, likely because of differences in the growth and sporulation of fungi under artificial conditions. Results indicate that the two fungi may offer complementary benefits to the mountain pine beetle because larvae preferentially fed on phloem colonized by both fungi together over phloem colonized by one fungus or uncolonized phloem. Teneral adults preemergence fed on spores in pupal chambers when they were produced and consumed little phloem before emerging. Teneral adults mined extensively in the phloem before emerging when spores were not produced in the pupal chamber. Our results provide evidence for a nutritional role of fungi in the diet of bark beetles and show that multiple associates may differentially affect beetle performance, which could have important implications for bark beetle population dynamics.},
	keywords = {Dendroctonus ponderosae},
	isbn = {0046-225X},
	author = {Bleiker, K. P. and Six, D.L.}
}
@article {8902,
	title = {Detection of host habitat by parasitoids using cues associated with mycangial fungi of the mountain pine beetle, Dendroctonus ponderosae},
	journal = {Canadian Entomologist},
	volume = {140},
	number = {1},
	year = {2008},
	month = {January-February},
	pages = {124-127},
	type = {Article},
	abstract = {Cues used by parasitoids to detect habitat of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), were investigated by observing parasitoid attraction to logs infested with D. ponderosae, logs inoculated with one or both of the symbiotic fungi of D. ponderosae (Grosmannia clavigera (Rob.-Jeffr. \& R.W. Davidson) Zipfel, ZW. de Beer \& M.J. Wingf. (Ophiostomataceae) and Ophiostoma montium (Rumbold) Arx (Ophiostomataceae)), logs containing no beetles or fungi, or empty screen cylinders. Captures of Heydenia unica Cook and Davis (Hymenoptera: Pteromalidae) and Rhopalicus pulchripennis (Crawford) (Hymenoptera: Pteromalidae) on logs with both G. clavigera and O. montium were greater than those from control treatments. These results suggest that characteristics of tree tissues simultaneously colonized by the two symbiotic fungi facilitate a detectable change in the volatile compounds released from D. ponderosae-attacked trees that may be used by parasitoids to locate hosts.},
	keywords = {Dendroctonus ponderosae},
	isbn = {0008-347X},
	author = {Adams, A. S. and Six, D.L.}
}
