Pine Wilt Nematode(Bursaphelenchus xylophilus)Latin Name: Bursaphelenchus xylophilus
Common Name: Pine Wilt Nematode
Appearance:
Mature pine wilt nematodes are about 1 mm long.
Pine wilt nematodes multiply quickly after infesting a host tree and prey on cells in the resin ducts.
Nematode injury limits water circulation within the tree and decreases resin synthesis.
Depending on the location of the infestation, this may manifest as wilting on a single branch, known as a “flag,” or over an entire tree. The tree will die because of the negative impacts over time.
These trees appeal to adult Monochamus beetles, who congregate on the trunks to mate.
Host plants:
Scots, mugo, red pines Austrian, jack, and, less commonly, white pines.
Territory:
Bursaphelenchus xylophilus is native to North America, mainly the United States, and was most likely spread elsewhere by contaminated timber/wood products. The nematode has been found in imported lumber in Finland, Norway, Sweden, and France.
Damage caused by Pine Wilt Nematode:
Pine wilt is a devastating disease that often destroys susceptible trees in weeks to months. Bursaphelenchus xylophilus, the causative pathogen is a pinewood nematode (PWN). Nematodes destroy the tree by feeding on the cells around the resin ducts. Just like a human cannot drink through a straw with holes, the tree cannot transfer water upward and wilts and dies.
Life history and Habits:
The pine wilt nematode may survive in both host plants and soil. While some transmission is possible by soil movement or contact with afflicted wood, the Japanese sawyer beetle and other Monochamus longhorn beetle species are the primary dissemination vectors. The pine wilt nematode’s life cycle includes a propagative cycle (from egg to adult) in which nematode larvae congregate in the pupal chamber of the Japanese sawyer beetle. Pine sawyer beetles can spread nematodes through wounds they create while eating on the bark of immature trees.
