Dothistroma needle blight (DNB) is one of the most important diseases of pine. Although its notoriety stems from Southern Hemisphere epidemics in Pinus radiata plantations, the disease has increased in prevalence and severity in areas of the Northern Hemisphere, including Europe, during the last two decades. This increase has largely been attributed to expanded planting of susceptible hosts, anthropogenic dispersal of the causative pathogens and changes in climate conducive to disease development. The last comprehensive review of DNB was published in 2004, with updates on geographic distribution and host species in 2009. Importantly, the recognition that two species, Dothistroma septosporum and D. pini, cause DNB emerged only relatively recently in 2004. These two species are morphologically very similar, and DNA-based techniques are needed to distinguish between them. Consequently, many records of host species affected or geographic location of DNB prior to 2004 are inconclusive or even misleading. The objectives of this review were (i) to provide a new database in which detailed records of DNB from 62 countries are collated; (ii) to chart the current global distribution of D. septosporum and D. pini; (iii) to list all known host species and to consider their susceptibility globally; (iv) to collate Drenkhan et al. 410 |

Summary Dothistroma needle blight (DNB), caused by Dothistroma septosporum and Dothistroma pini, and brown spot needle blight (BSNB), caused by Lecanosticta acicola, are some of the most serious and damaging foliar diseases of pines (Pinus spp.). Lecanosticta acicola is reported for the first time from Ireland and Portugal and confirmed from the Black Sea coast of Russia (Krasnodar region, Sochi). It has also been recovered from the first, and only, reported site in Latvia 4 years after efforts to eradicate it were undertaken. Dothistroma septosporum is reported for the first time from Ireland on Pinus sylvestris and Pinus radiata. It was also found in Comunitat Valenciana, Spain, and confirmed as the causal agent of the disease in Bulgaria. Dothistroma pini was found in Aragon, Spain, and in Arkansas, USA, where it was found on Pinus elliottii, a new host for this pathogen. A new ITS haplotype of D. septosporum is reported from the Bulgarian isolates and a new ITS haplotype of D. pini from the Arkansas isolates. These new country and regional reports extend the geographical and host range of these pathogenic fungi and continue a trend seen since the 1990s. Of particular concern are the geographically widespread new reports of L. acicola from the most north‐ and south‐westerly (Ireland and Portugal) to the most south‐easterly (Russia) regions in Europe, suggesting that not only is this pathogen continuing to spread in Europe but also is well adapted to a wide range of climatic conditions.

Summary Dothistroma needle blight (DNB) caused by Dothistroma septosporum and Dothistroma pini is a damaging disease of pine in many countries. The disease led to the abandonment of planting susceptible Pinus species in parts of Africa, Asia, Australasia, Europe and North America. Although the disease can be effectively controlled using copper fungicides, this chemical is only routinely applied in forests in New Zealand and Australia. Other management tactics aimed at making conditions less favourable for disease development, such as thinning or pruning, may be effective on some, but not all, sites. Disease avoidance, by planting non‐susceptible species, is the most common form of management in Europe, along with deployment of hosts with strong disease resistance. Although D. septosporum is present almost everywhere Pinus is grown, it is important that an effort is maintained to exclude introductions of new haplotypes that could increase virulence or enable host resistance to be overcome. A global strategy to exclude new introductions of Dothistroma and other damaging forest pathogens, facilitated by collaborative programmes and legislation, is needed.