|Wick, Robert - University Of Massachusetts|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/7/2018
Publication Date: N/A
Interpretive Summary: Nematodes are microscopic worms that attack plants and cause billions of dollars of damage to crops and forest and ornamental trees. Because presence of the pinewood nematode (PWN) in U.S. wood products prevents their export, nematode specimens from surveys are often submitted to pest diagnostic laboratories. In this study, scientists from the University of Massachusetts, Amherst and USDA-ARS Beltsville describe the identification of a nematode found in association with pine destined for export both microscopically and with four molecular markers. The data indicated that the nematode was not PWN but actually a relative previously identified from maritime pine in Portugal. The results are significant because this is the first report of this nematode species in the United States and because it may be spread by insects similar to those found associated with the species in Portugal. The description and related information will be used by survey personnel and regulators to refine surveillance and detection efforts to protect pines in the U.S.
Technical Abstract: Juvenile, female and male nematodes were discovered in wood chips of white pine Pinus strobus from Ashley Falls, Massachusetts (MA), USA. Initial observations suggested these nematodes might be Bursaphelenchus xylophilus, but closer morphological and molecular characterization proved otherwise. Comparison of measured features with those in the literature indicated this nematode population had some characteristics distinguishing it from B. xylophilus. The specimens were identified as Bursaphelenchus antoniae Penas et al., 2006 based on 18S rDNA molecular sequence with only 95% similarity to that of B. xylophilus. Compared to the previously described Portuguese population of B. antoniae, the sequences generated for the MA population were 98.3% similar for ITS1,2 rDNA and 99.9% similar for 28S rDNA. There was 99.2% similarity between the COI sequences of the U.S. and Portuguese isolates of B. antoniae. This population has morphology consistent with that of Penas et al., 2006; however, the female tail on this MA pine population is mucronate and more attenuated than in B. antoniae from Portuguese P. pinaster. Ecological associations of both populations of B. antoniae are discussed.