An infestation of a bark beetle species capable of vectoring pathogenic fungi was recently found in North America.
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Nombre: Hylurgus ligniperda Fabricius
Animalia: Arthropoda: Insecta: Coleoptera: Scolytidae
Nombre común: red-haired pine bark beetle; golden-haired bark beetle
An infestation of H. ligniperda was discovered at a Christmas tree plantation in Rochester, NY, in November, 2000.
Preocupación: Previously, single H. ligniperda adults were trapped in Monroe County, 20 miles west (upwind) of the Rochester site in both 1994 and 1995. Surveys conducted in spring and summer 2001detected small numbers of adult H. ligniperda at single locations in two adjacent counties (Wayne and Ontario), as well as two locations in Monroe county. Surveys in five other adjacent counties were negative.
Adult H. ligniperda are attracted to fresh stumps, slash and logging debris for breeding. In unhealthy Pinus spp., the beetle usually breeds in thick bark near the base of the stem or in large exposed roots. Newly emerged adults may attack seedlings and stressed pole-sized trees.
Adult beetles are efficient vectors of Leptographium fungi, which have been implicated in pine root decline diseases. Leptographium procerum, often isolated from New Zealand populations of H. ligniperda, is the cause of Procera root disease, found in white pines in the eastern U.S.
Leptographium wageneri, the causal agent of black stain root disease, is currently present in the western U. S. There is concern that H. ligniperda could be an efficient vector of this fungus if the range of the beetle and the fungus were ever to overlap. The H. ligniperda colony recently discovered in NY yielded 20 isolates of Leptographium fungi (as yet unidentified to species).
Hylurgus ligniperda is occasionally intercepted at U. S. ports in association with solid wood packing materials from Europe. Dispersal on Christmas trees is unlikely because the adults primarily infest stumps and roots and are not flying when the trees are harvested.
Hospedantes: Several species within the genus Pinus (pines).
Africa, Asia (Japan and Sri Lanka), Australasia and South Pacific (Australia and New Zealand), Europe, North America (U. S. - infestation in NY) and South America (Brazil and Chile).
Cuarentenas: Hylurgus ligniperda is a quarantine-significant pest for numerous countries.
Estrategias de detección
Placement of trap logs and survey of pine cull trees, slash piles and stumps are survey methods which may be of use. Tools should be used for prying open pine wood, branches and stumps.
A recent study by the USDA Forest Service found Lindgren funnel traps with high release alpha-pinene (625 mg/day = 5 standard lures) + high release ethanol (1000 mg/day) to be the most effective of the trap-lure combinations they tested. Other lures tested in this study also proved effective, but to a lesser degree. Intercept panel traps and Theysohn traps may be used in conjunction with high release alpha pinene + high release ethanol. Lindgren funnel traps should be hung from a trap rod with top of trap appox. 6 feet from the ground, with the ethanol attractand hung from the top funnel down through the inside of the funnels below. The alpha pinene should be attached below the ethanol, and these attractants should not touch each other.
Adult H. ligniperda are good fliers and can disperse over several kilometers in response to host volatiles. The infestation in the Rochester, NY, area is moving slowly by natural means. Hylurgus ligniperda is present in a wide range of climates throughout the world, so it could potentially survive in all regions of the U. S.
In 2001, H. ligniperda appeared to complete two generations in New York, with the first developing from May to mid-July and the second from mid-July to September. Adult flight activity was heaviest from September to November, corresponding with the second generation's emergence. However, there was no similar increase in July, suggesting that brood adults continued to breed in the same stumps in which they developed.
The most promising methods of control are silvicultural controls, including removal of tree stumps and logging debris, as well as delaying the replanting of pine plantations for 6-9 months following harvest. Biological control (for example, using predatory clerid beetles) may be of some use in light infestations.
Otro tipo de información:
Forest and Timber Insects in New Zealand No. 18
The Exotic Forest Pest Information System for North America
Solid Wood Packing Materials PRA (H. ligniperda on p. 183)