PHRAME work packages

Work Package 1:
Vector surveys and biology

The principal objective is to determine the distribution of Monochamus spp. (vectors of the pine wood nematode) in the Iberian peninsula, and to collect information about their biology, especially the flight period and any Bursaphelenchus spp. carried by the beetles.

Sampling in the Setubal region of Portugal will aim to detect vector(s) active in the current B. xylophilus infestation, with emphasis on M. galloprovincialis. This information will be used for elaboration of control measures against the beetles that should prove to be the most effective means of managing Bursaphelenchus. Moreover, the distribution of Monochamus and the presence of B. mucronatus on the vector will provide a means to indicate highest risk regions for establishment of B. xylophilus. The number of B. xylophilus carried by the longhorn beetles is an important indicator for a possible epidemic spread of pine wilt.

Other wood- and bark-breeding beetles, especially bark beetles may also play a role as vectors of B. xylophilus and will be investigated.

Work Package 2:
Survey of Bursaphelenchus spp., wilt expression and quantification of nematode-vector relationships

The principal objective is to evaluate the extent of establishment of B. xylophilus in the Iberian Peninsula. Since Portuguese wood is mainly exported to Spain, there is a high probability of dissemination of B. xylophilus to Spain. Eco-climatic conditions in Spain are favourable for pine wilt disease, and the proximity to Portugal could permit natural spread of the nematode between the two countries. Since other Bursaphelenchus species may also possess a phytopathogenic potential, their distribution and host preferences will also be recorded. Partner 7 will make Bursaphelenchus samples collected during the EU surveys in France available for inclusion in the investigations.

Work Package 3:
Collection of eco-climatic data, construction of sub-models and prediction of wilt-risk areas

The association between the severity of nematode attack and underlying ecological parameters will be thoroughly investigated and correlated. National forest services will supply important and accurate information on the ecosystem. Specific biotic and abiotic parameters in the region, such as high summer temperatures, low precipitation, extensive fire outbreaks and the reduction of forest land, necessitates immediate studies in relation to their roles on Bursaphelenchus and Monochamus occurrence in Mediterranean forests.

The main objective will be to investigate ecological variables that explain the nematode's presence in Portugal, in order to establish an ecological optimum for the nematode and its vectors. Meteorological variables will be thoroughly investigated; also landscape variables and land use will be considered.

Work Package 4:
Development of methods for accurate early detection of wilt expression in standing trees

The objective of this workpackage is the development of methods for early detection of Bursaphelenchus nematodes in living trees. To prevent spread of nematodes and attack of nematode-infested trees by egg-laying longhorn beetles, infested trees should be removed as early as possible. However, nematode distribution within trees is very irregular initially and difficult to detect by sampling. The increase of the nematode population in xylem and the collapse of the cambium-phloem zone will lead to a change in the water regime and resin flow of the infested tree. This could be measured by different instruments and methods.

Work Package 5:
Establishment of nematode cultures, mass production and cryopreservation

  • Maintenance and enlargement of the living collection of Bursaphelenchus spp. and strains (geographic provenances) by Partner 7 and Partner 2, as reference material for identification, for taxonomic and molecular biological research and for teaching identification methods of Bursaphelenchus in surveys within the EU.
  • Production of large numbers of nematodes of defined strains, as required for pathogenicity testing (Work Package  6).
  • Providing moderate nematode numbers of a variety of B. xylophilus strains from different geographic origins for molecular biological pathway analysis (Work Package  7).
  • Partner 7 and Partner 2 will cooperate on elaboration of methods for maintenance of live nematodes by cryopreservation.

Work Package 6:
Evaluation of relative pathogenicity of Portuguese Bursaphelenchus xylophilus in European pines and model construction

To obtain detailed information on the pathogenicity of the Portuguese isolate(s) of B. xylophilus in comparison to known provenances of the nematode, pathogenicity data will be obtained in climate chambers under variable temperatures and under outdoor conditions in Portugal using various European pine species.

Work Package 7:
Use of B. xylophilus isolates to define pathways for entry to Portugal and construction of pathway sub-model

The objective is to obtain information on the area of origin and the pathway of introduction of the B. xylophilus strain detected in Portugal. It is very important to determine the potential pathways for introduction of this serious pest to Europe because efforts to eradicate the nematode in Portugal will be in vain if introductions occur repeatedly. This issue is also very important in order to better protect other EU countries from introduction of the nematode.

Identification of the pathway will also enable existing risk reduction measures within EU legislation to be assessed for efficacy and, if necessary, recommend more stringent measures in relation to future imports from the country of origin of the nematode.

Work Package 8:
New literature review and use of phenology data to construct sub-model

To carry out a new literature review and to update an information database on B. xylophilus and Monochamus spp. in a world-wide context. Special attention will be paid to information from China where the nematode is a relatively new arrival and is still spreading, and to quantitative information on the phenologies of B. xylophilus and Monochamus spp. Information will be prepared in a form suitable for inclusion in GIS and CLIMEX predictive models.

Work Package 9:
Develop GIS and CLIMEX models and incorporate into new PRA process model to be tested and verified using Bursaphelenchus xylophilus and Monochamus spp. as test organisms

Development of refined Pest Risk Analysis (PRA) tools using B. xylophilus and its inter-relations with native Monochamus spp. in Europe as a model system. This includes:

  • Detailed assessments of the biologies of both pests
  • Collection of data on their phenological development
  • Application of Geographic Information System (GIS) and CLIMEX modelling for predictions of risk under various assumptions of management strategies
  • Construction of process-based PRA output models for sensitivity analysis in relation to various management options.