Assessment of Dothistroma genetic diversity in Britain

The aim of this work is to explore whether the increased prevalence and severity of DNB could be due to genetic changes in the pathogen or the arrival of novel forms of D. septosporum or even D. pini.

Research objectives

  • Determine if D. pini, the second causal agent of DNB, is present in Britain
  • Investigate the genetic diversity of D. septosporum populations in Britain using microsatellite markers (SSRs)
  • Determine whether one or multiple populations are responsible for the disease in Britain
  • If multiple populations are responsible, assess whether they are geographically delimited.

Results so far

Over 1,000 Dothistroma isolates have been analysed to date. No D. pini has been found in any UK pine samples, all are D. septosporum. Six distinct D. septosporum populations occur in Britain, each with varying levels of genetic diversity. Two populations are distributed throughout the entire island and have high levels of genetic diversity; therefore the possibility of their being native cannot be excluded. Two additional populations occurred only in England and Wales, one of which is appears to have it origins in the first outbreak of DNB dating back to the 1950s. The remaining two populations are unique to Scotland.


Research into the diversity and population structure of Dothistroma began in 2011 and was completed in April 2016.

Related Services

To report a finding of Dothistroma to Forest Research scientists please use TreeAlert

Related Resources

Pests and diseases: Dothistroma needle blight

Disease symptoms and life cycle

Pathogens and hosts of DNB

Status of the disease in Britain

Dothistroma needle blight FC webpage

Dothistroma needle blight Questions and Answers


Martin Mullett

Funders and Partners

Forestry Commission and Imperial College London 

Funded as part of the Forestry Commission Advice and Scientific Support for Tree Health Programme

Forestry Commission policy
This research underpins the evidence base for the delivery of healthy and resilient forests and wider ecosystems which is part of the Tree Health and Plant Biosecurity Action Plan