INSECT-SYMBIONT INTERACTIONS Nitrogen Concentration in Mountain Pine Beetle Larvae Reflects Nitrogen Status of the Tree Host and Two Fungal Associates
نویسندگان
چکیده
Individual lodgepolepines(Pinus contorta)were fertilizedwithureaatnitrogen(N) inputs equivalent to 0, 315, or 630 kg/ha. Four months after application of the fertilizer, inner bark tissue N concentrations were signiÞcantly higher in the trees that had received the low dose (315 kg/ha) fertilization treatment than in the control trees; trees that had received the high-dose treatment (630 kg/ha) were intermediate and not signiÞcantly different from either of the other treatments. There was a signiÞcant positive correlation between N concentration in inner bark tissue and larval mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae). In vitro studies on synthetic growthmedia examined effects of temperature andN concentration onN concentration of two common fungal associates of the mountain pine beetle (Ophiostoma clavigerum and Ophiostoma montium). Increasing N concentration in growth media signiÞcantly increased fungal N concentrations in both O. clavigerum andO. montium. Furthermore, N concentration was consistently higher inO. clavigerum than in O. montium. Neither species had sufÞcient growth at 30 C, nor did O. clavigerum at 15 C, to test N concentration. However, for O. montium, increasing temperatures decreased fungal N concentrations. There was no correlation between N concentration of O. clavigerum and growth temperature. Potential impacts of ingestion of the fungal species by developingmountain pine beetle larvae-infesting trees under various environmental conditions such as increasing temperatures are discussed.
منابع مشابه
Nitrogen concentration in mountain pine beetle larvae reflects nitrogen status of the tree host and two fungal associates.
Individual lodgepole pines (Pinus contorta) were fertilized with urea at nitrogen (N) inputs equivalent to 0, 315, or 630 kg/ha. Four months after application of the fertilizer, inner bark tissue N concentrations were significantly higher in the trees that had received the low dose (315 kg/ha) fertilization treatment than in the control trees; trees that had received the high-dose treatment (63...
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