It is present in Japan.
In the EPPO region, it is considered to have been introduced in the Netherlands prior to World War II with material imported from Japan for breeding purposes. It has a restricted distribution in the Netherlands, Italy and France, at few sites, to date only in very specific environments. In the three countries, it has been found in experimental fields for elm improvement programmes, and in the Netherlands, also in a botanical garden, on street trees, and in a facility in a city formerly producing plants to be planted in the municipality.
Elm trees grown on the infested plots in the Netherlands (breeding programme for resistance against the Dutch elm disease due to Ophiostoma ulmi) have been sent to 10 European countries (Belgium, Denmark, France, Germany, Ireland, Italy, Spain, Slovakia, Romania, UK). There is an uncertainty on whether the nematode is present in some countries that have received this material, in particular where no specific sampling of the roots has been done.
No precise information was available regarding the damage by M. mali in Japan, but M. mali is mentioned in general terms as ‘one of the most important nematodes injuring apple trees in Japan’ and as ‘causing reduction in plant growth and fruit yield’. In the few sites where it was found in the EPPO region, it has caused so far minor damage through uprooted trees, only in the Netherlands.
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