Indexed on: 10 Mar '19Published on: 01 Sep '99Published in: Plant Disease
Pine forests are important elements of natural ecosystems in Greece. Pines are very well adapted to the ecoclimatic conditions of this country and are extensively used in plantations. While there is danger of accidental introduction of Bursaphelenchus xylophilus into Europe through timber trade, in recent years pine wilting of unknown cause has been observed in many European countries. In many cases various Bursaphelenchus spp. have been isolated from wilting conifer species (1-3). A survey for nematodes of pine in Greece was carried out from 1996 to 1998, as part of a project (FAIR 1CT 95-0083) funded by the European Commission, in which five European countries are involved. Trees chosen for sampling were either dying or recently dead. From each tree, three disks 10 cm in thickness were cut, from the lower, medium, and upper parts of the main stem. The bark was removed and Baermann-funnel-extraction for nematodes was immediately carried out for 48 h at room temperature. During the 3 years of the survey, samples from 93 pine trees from different areas of Greece were examined. Samples were obtained from the indigenous species Pinus brutia, P. halepensis, P. nigra, and P. sylvestris as well as the exotic species P. pinaster and P. radiata. Thirty-two of the samples were found infected by different species of Bursaphelenchus. B. eggersi Ruhm was isolated from P. pinaster, B. hellenicus Skarmoutsos, Braasch, and Michalopoulou from P. brutia, and B. leoni Baujard from P. brutia, P. nigra, P. pinaster, and P. radiata. B. sex-dentati Ruhm, the most abundant of all species, was recovered from P. brutia, P. halepensis, P. nigra, P. pinaster, and P. radiata, whereas B. teratospicularis Kakuliya was isolated from P. brutia and P. halepensis. Samples from P. sylvestris did not yield any Bursaphelenchus nematodes. All isolated species constitute a first record in Greece with B. hellenicus described as a new species (4). This study on the relationship between dead and dying pines and nematodes of the genus Bursaphelenchus is the first undertaken in this country. References: (1) P. Baujard. Rev. Nématol. 3:167, 1980. (2) A. Marinari Palmisano and L. Ambrogioni. Redia 77:225, 1994. (3) J. Philis and H. Braasch. Nematol. Mediterr. 24:119, 1996. (4) G. Skarmoutsos et al. Nematologica 44:623, 1998.