An accurate model of the Pine Wood Nematode invasion in Europe


Tuesday, 30 May 2018

The pine wood nematode (PWN), Bursaphelenchus xylophilus, is a species native to North America, introduced in Europe in 1999 in southwestern Portugal, causing considerable damages to Portuguese forest ecosystems and now spreading towards Spain. A new study, by the Universidad Polit├ęcnica de Madrid and the Joint Research Centre of the European Commission, has produced a predictive model for forecasting the expansion of this invasive species and the efficacy of certain measures to stop it. The model was able to reproduce more than a decade of PWN spread in Portugal with high accuracy, suggesting that it can be used as a tool for management by forecasting how the species will spread to other parts of Europe in the absence of efficient containment measures. In addition, the model developed by the scientists can simulate how effective certain measures, and their combination, can be at halting or slowing down the PWN spread. These measures include clear-cut belts, mass trapping of the insect vector of the nematode during the flight period, and the early detection and removal of infected trees during winter.

Nematodes constitute an animal phylum inhabiting a broad range of environments. It is estimated that four of every five animals on earth are nematodes, while more than half of these species are pests causing significant damages on a number of crops. Several nematodes are listed as invasive, and their introduction related to global trade and movement of goods.  The International Standards For Phytosanitary Measures No. 15 (ISPM 15) contains specific measures on wood packing material, developed by the International Plant Protection Convention (IPPC) for preventing the international transport and spread of diseases, insects and other pests that could negatively affect plants or ecosystems, protecting crops and the native ecosystems around the globe.