SummaryAn analysis of incidence of Phytophthora spp. in 732 European nurseries producing forest transplants, larger specimen trees, landscape plants and ornamentals, plus 2525 areas in which trees and shrubs were planted, is presented based on work conducted by 38 research groups in 23 European countries between 1972 and 2013. Forty-nine Phytophthora taxa were recorded in 670 nurseries (91.5%); within these nurseries, 1614 of 1992 nursery stands (81.0%) were infested, although most affected plants appeared healthy. In forest and landscape plantings, 56 Phytophthora taxa were recovered from 1667 of 2525 tested sites (66.0%). Affected plants frequently showed symptoms such as crown thinning, chlorosis and dieback caused by extensive fine root losses and/or collar rot. Many well-known highly damaging host-Phytophthora combinations were frequently detected but 297 and 407 new Phytophthora-host associations were also observed in nurseries and plantings, respectively. On average, 1.3 Phytophthora species/taxa per infested nursery stand and planting site were isolated. At least 47 of the 68 Phytophthora species/taxa detected in nurseries and plantings were exotic species several of which are considered well established in both nurseries and plantings in Europe. Seven known Phytophthora species/taxa were found for the first For. Path. 46 (2016) 134-163 doi: 10.1111/efp.12239 © 2015 http://wileyonlinelibrary.com/ time in Europe, while 10 taxa had not been previously recorded from nurseries or plantings; in addition, 5 taxa were first detections on woody plant species. Seven Phytophthora taxa were previously unknown to science. The reasons for these failures of plant biosecurity in Europe, implications for forest and semi-natural ecosystems and possible ways to improve biosecurity are discussed.

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 |

Extensive die-back and mortality of various ornamental trees and shrubs has been observed in parts of the Western Balkans region during the past decade. The disease symptoms have been typical of those caused by pathogens residing in the Botryosphaeriaceae. The aims of this study were to isolate and characterize Botryosphaeriaceae species associated with diseased ornamental trees in Serbia, Montenegro, Bosnia and Herzegovina. Isolates were initially characterized based on the DNA sequence data for the internal transcribed spacer rDNA and six major clades were identified. Representative isolates from each clade were further characterized using DNA sequence data for the translation elongation factor 1-alpha, b-tubulin-2 and large subunit rRNA gene regions, as well as the morphology of the asexual morphs. Ten species of the Botryosphaeriaceae were identified of which eight, i.e., Dothiorella sarmentorum, Neofusicoccum parvum, Botryosphaeria dothidea, Phaeobotryon cupressi, Sphaeropsis visci, Diplodia seriata, D. sapinea and D. mutila were known taxa. The remaining two species could be identified only as Dothiorella spp. Dichomera syn-asexual morphs of D. sapinea, Dothiorella sp. 2 and B. dothidea, as well as unique morphological characters for a number of the known species are described. Based on host plants and geographic distribution, the majority of Botryosphaeriaceae species found represent new records. The results of this study contribute to our knowledge of the distribution, host associations and impacts of these fungi on trees in urban environments.

Armillaria possesses several intriguing characteristics that have inspired wide interest in understanding phylogenetic relationships within and among species of this genus. Nuclear ribosomal DNA sequence-based analyses of Armillaria provide only limited information for phylogenetic studies among widely divergent taxa. More recent studies have shown that translation elongation factor 1-α (tef1) sequences are highly informative for phylogenetic analysis of Armillaria species within diverse global regions. This study used Neighbor-net and coalescence-based Bayesian analyses to examine phylogenetic relationships of newly determined and existing tef1 sequences derived from diverse Armillaria species from across the Northern Hemisphere, with Southern Hemisphere Armillaria species included for reference. Based on the Bayesian analysis of tef1 sequences, Armillaria species from the Northern Hemisphere are generally contained within the following four superclades, which are named according to the specific epithet of the most frequently cited species within the superclade: (i) Socialis/Tabescens (exannulate) superclade including Eurasian A. ectypa, North American A. socialis (A. tabescens), and Eurasian A. socialis (A. tabescens) clades; (ii) Mellea superclade including undescribed annulate North American Armillaria sp. (Mexico) and four separate clades of A. mellea (Europe and Iran, eastern Asia, and two groups from North America); (iii) Gallica superclade including Armillaria Nag E (Japan), multiple clades of A. gallica (Asia and Europe), A. calvescens (eastern North America), A. cepistipes (North America), A. altimontana (western USA), A. nabsnona (North America and Japan), and at least two A. gallica clades (North America); and (iv) Solidipes/Ostoyae superclade including two A. solidipes/ostoyae clades (North America), A. gemina (eastern USA), A. solidipes/ostoyae (Eurasia), A. cepistipes (Europe and Japan), A. sinapina (North America and Japan), and A. borealis (Eurasia) clade 2. Of note is that A. borealis (Eurasia) clade 1 appears basal to the Solidipes/Ostoyae and Gallica superclades. The Neighbor-net analysis showed similar phylogenetic relationships. This study further demonstrates the utility of tef1 for global phylogenetic studies of Armillaria species and provides critical insights into multiple taxonomic issues that warrant further study.

Diplodia sapinea is an important pathogen of pine trees in plantations and urban areas in many parts of the world. This pathogen has recently also been isolated from diseased Cedrus atlantica, C. deodara and Picea omorika planted as ornamentals across the Western Balkans. The aim of this study was to consider the host range of D. sapinea in Serbia and Montenegro. Diplodia sapinea was identified from a broader collection of Botryosphaeriaceae from the Western Balkans region, based on the DNA sequence data for the internal transcribed spacer (ITS) rDNA and the translation elongation factor 1α (TEF 1α). The D. sapinea isolates were obtained from sixteen tree species in the genera Abies, Cedrus, Chamaecyparis, Juniperus, Picea, Pinus, Pseudotsuga and Fagus. Four species represented new hosts in the Balkans, and this is the first report of D. sapinea from F. sylvatica anywhere in the world. Pathogenicity tests were conducted on the tree hosts from which D. sapinea was isolated, as well as on P. abies, Thuja occidentalis, Prunus laurocerasus, Eucalyptus grandis and P. patula. Inoculations were made on seedlings in the field, in the greenhouse or on freshly detached branches.Inoculations on P. pungens, P. omorika, P. abies, P. menziesii, A. concolor, P. nigra and P. sylvestris resulted in death of the seedlings 5-16 weeks after inoculation. Diplodia sapinea produced lesions on J. horizontalis and P. patula seedlings and F. sylvatica cut branches. Reciprocal inoculations showed that D. sapinea is not a pine-specific pathogen, causing disease on tree species, including those from which it had not been isolated. Not surprisingly, the pathogen was most aggressive on some species of Pinaceae.

Armillaria causes problems of root rot, kill trees and decay wood in the forests of Serbia and Montenegro, but the species involved have not hitherto been identified. The aim of this study was to identify field isolates collected on 25 localities. Identification was based on restriction fragment length polymorphism (RFLP) analysis of intergenic spacer 1 (IGS1) region and comparisons of IGS1 sequence with those available on NCBI database. Phylogenetic analysis was performed on sequence information from selected isolates to determine possible interrelationships between isolates with different banding patterns and previously identified tester isolates of five European Armillaria species. Five Armillaria species were identified in 90 isolates obtained from forests in Serbia and Montenegro. Armillaria gallica was most frequently isolated, followed by A. cepistipes, A. mellea, A. ostoyae and A. tabescens; two isolates remained unidentified. Restriction digestion of IGS1 amplification products with AluI produced 10 RFLP patterns. Patterns G4 (400, 250, 180) for A. gallica and pattern X (400, 180, 140) for isolates 74 and 79 are reported for the first time in European isolates. Eight RFLP patterns were observed after restriction with TaqI. Two patterns each were observed for A. ostoyae and A. gallica, and one each for A. cepistipes, A. mellea, A. tabescens and isolates 74 and 79. Parsimony analyses based on the IGS1 region placed the isolates into four clades: one including A. mellea, the second containing A. gallica-A. cepistipes isolates, while isolates of A. ostoyae and A. borealis were in the third clade. Armillaria tabescens differed from all annulate species. Phylogenetic analysis supported the conclusion that European Armillaria species are closely related and separated from a common ancestor in the near past. According to this survey five European Armillaria species are present in the forests of Serbia and Montenegro, while A. borealis is not present in the studied ecosystems.

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The distribution of Armillaria species was investigated in Serbian forest ecosystems, in relation to the main host species attacked, forest-types, geography and altitude. In total, 388 isolates were identified from 36 host species in 47 sites. Armillaria gallica was the most commonly observed species with the widest distribution and with an altitudinal range of 70-1450 m, it was the dominating Armillaria species in lowland alluvial forests and in Quercus and Fagus forests at higher elevations. Armillaria mellea occurred in Quercus spp. -dominated forests in the north and central regions at 70-1050 m. Sixty-eight per cent of the A. mellea isolates were collected from living hosts, most commonly in declining conifer plantations. Armillaria ostoyae was distributed in the cooler coniferous forest types and plantations in the Dinaric Alps in the south of Serbia, at 850-1820 m. Armillaria cepistipes was found in the eastern and southern hilly and mountainous regions of the country, at 600-1900 m. Most isolates were obtained from conifers and rhizomorphs in the soil around decaying stumps. Armillaria tabescens was found only on dead oak material in the northern and eastern regions of the country at altitudes lower than 600 m.