Enhanced colonization by the blue stain fungus Ophiostomaclavigerum in glyphosate-treated sapwood of lodgepole pine

1992 ◽  
Vol 22 (2) ◽  
pp. 206-209 ◽  
Author(s):  
D.J. Bergvinson ◽  
J.H. Borden

The herbicide glyphosate was administered into the sapwood around the root collar of lodgepole pine trees, Pinuscontorta var. latifolia Engelm., to determine its effect on invasion by the blue stain fungus Ophiostomaclavigerum (Robinson-Jeffrey & R.W. Davidson) T.C. Harrington. In two experiments, lesions in the sapwood were longer and wider in trees treated with glyphosate before inoculation with O. clavigerum than in untreated, control trees. Ophiostomaclavigerum was recovered in a third experiment at seven times the distance from the point of inoculation in trees treated with glyphosate 3 weeks before inoculation as in untreated, control trees. We conclude that previously observed enhancement of brood development of the mountain pine beetle, Dendroctonusponderosae Hopk., was caused by glyphosate--induced inhibition of the trees' secondary defense response to invasion by the beetle's symbiotic fungi.

1961 ◽  
Vol 37 (4) ◽  
pp. 368-375 ◽  
Author(s):  
R. W. Reid

The moisture content of the outer sapwood of non-infested lodgepole pine is normally about 85 to 165 per cent of oven dry weight. In trees that have been infested by the mountain pine beetle for one year, the sapwood moisture content can be as low as 16 per cent. There is a steep moisture gradient from about 160 per cent in the outer sapwood to about 30 per cent in the heart-wood. The moisture content in the centre is slightly higher than in the adjacent wood. In infested trees the sapwood moisture is greatly reduced within a year after the attack but moisture in the heartwood is not altered appreciably. Trees infested early in the season drop to a lower moisture content by fall than trees infested later in the season. In non-infested trees there is a diurnal and a seasonal moisture march; these do not occur in infested trees. The rapid moisture loss in the sapwood of infested trees is associated with blue-stain infection and successful establishment of bark-beetle broods


1986 ◽  
Vol 16 (5) ◽  
pp. 1036-1040 ◽  
Author(s):  
R. H. Miller ◽  
A. A. Berryman

Healthy lodgepole pine trees (Pinuscontorta Dougl. var. latifolia Engelm.) were girdled on the lower trunk in patterns designed to selectively eliminate the influence of materials transported from the roots, lateral tissues, and crown. Titres of soluble sugars and starch observed in areas isolated by girdling were significantly lower than those observed in areas open to the upper bole and crown. Corresponding decreases were observed in the numbers of Dendroctonusponderosae Hopkins attacking those areas.


1987 ◽  
Vol 65 (1) ◽  
pp. 95-102 ◽  
Author(s):  
H. S. Whitney ◽  
R. J. Bandoni ◽  
F. Oberwinkler

A new basidiomycete, Entomocorticium dendroctoni Whitn., Band. & Oberw., gen. et sp. nov., is described and illustrated. This cryptic fungus intermingles with blue stain fungi and produces abundant essentially sessile basidiospores in the galleries and pupal chambers of the mountain pine bark beetle (Dendroctonus ponderosae Hopkins Coleoptera: Scolytidae) in lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.). The insect apparently disseminates the fungus. Experimentally, young partially insectary reared adult beetles fed E. dendroctoni produced 19% more eggs than beetles fed the blue stain fungi.


1990 ◽  
Vol 20 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Y. Yamaoka ◽  
R. H. Swanson ◽  
Y. Hiratsuka

In two separate experiments in the field, healthy 80-year-old lodgepole pine (Pinuscontorta Dougl. var. latifolia Engelm.) were inoculated with four blue-stain fungi that are associated with mountain pine beetle (Dendroctonusponderosae Hopk.) and beetle-attacked trees. Inocula of Ophiostomaclavigerum (Robins.-Jeff. & Davids.) Harrington, O, huntii (Robins.-Jeff.) de Hoog & Scheffer, O. montium (Rumb.) von Arx, and O. minus (Hedge.) H. & P. Sydow were prepared on sawdust media. Inoculum was placed under the bark in two areas (8 × 5 cm each), one above the other, separated by a 15-cm space in which heat pulse velocity (HPV) sensors were installed. HPVs in the inoculated trees were monitored daily for 4 weeks. In sections inoculated with O. clavigerum, HPVs were significantly reduced 10 to 13 days after inoculation in both experiments. Sapwood under the inoculated area was visibly altered and colonized by the fungus. The other three fungi did not significantly reduce HPVs. These results proved the capability of O. clavigerum to colonize functional sapwood and stop sap flow within a short period of time and reconfirmed the importance of this fungus in the mortality of trees attacked by mountain pine beetle.


1987 ◽  
Vol 2 (4) ◽  
pp. 114-116 ◽  
Author(s):  
Patrick J. Shea ◽  
Mark McGregor

Abstract A large-scale field experiment was conducted on the Flathead National Forest, Montana, to evaluate the efficacy of 0.5%, 1.0%, and 2.0% formulations of Sevimol® and Sevin brand XLR® for protecting individual lodgepole pines (Pinus contorta var. latifolia Engelm.) from attack by mountain pine beetles (Dendroctonus ponderosae Hopk.). All concentrations and formulations were highly effective (>95%) in protecting lodgepole pine trees from lethal attack by mountain pine beetle for 1 year, and the 1% and 2% concentrations were effective (>90%) for 2 years. West. J. Appl. For. 2(4):114-116, October 1987


2007 ◽  
Vol 85 (3) ◽  
pp. 316-323 ◽  
Author(s):  
A.V. Rice ◽  
M.N. Thormann ◽  
D.W. Langor

Mountain pine beetle (MPB) is the most serious pest of lodgepole pine in western Canada, and it is predicted to spread into boreal jack pine within the next few years. Colonization of host trees by MPB-associated blue-stain fungi appears to be required for successful beetle reproduction. Three species of blue-stain fungi, Grosmannia clavigera (Robinson-Jeffery and Davidson) Zipfel, de Beer, and Wingfield (≡ Ophiostoma clavigerum (Robinson-Jeffery and Davidson) Harrington), Ophiostoma montium (Rumbold) von Arx, and Leptographium longiclavatum Lee, Kim, and Breuil, are associated with MPB in Alberta. In inoculation experiments, all three fungi caused lesions on lodgepole pine, jack pine, and their hybrids. On average, lesions were longer on jack pine and hybrids than on lodgepole pine, suggesting that fungal development will not be a barrier to MPB success in these trees. Differences in lesion length caused by the three fungal species were minimal, with significant differences observed only on hybrid pine and between O. montium and the other fungal treatments. On average, lesions caused by combinations of the three fungi (pair-wise and all together) did not differ significantly in length from those caused by the fungi singly, and none of the fungal species competitively excluded any of the others. These observations suggest that all three species are pathogenic to boreal pines and that the virulence of all three species is comparable.


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