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Öğe Armillaria ostoyae in managed coniferous forests in Kastamonu in Turkey(Wiley, 2017) Lehtijaervi, Asko Tapio; Dogmus-Lehtijarvi, H. T.; Kaya, A. G. Aday; Unal, S.; Woodward, S.Although several Armillaria species have been reported in Turkey, there is little information about their ecology in Turkish forests. In this study, we investigated five forest stands, approximately 5-74ha in size, in Kastamonu province in the Black Sea Region of Turkey for the presence of Armillaria species in stumps and logs. The stands were mixed Abies nordmanniana ssp. bornmulleriana and Pinus sylvestris forests managed using a selective cuttings system; the proportion of fir in the total number of stems and stumps ranged from 36 to 98%. Based on sequence analysis of the internal transcribed spacer and intergenic spacer regions of the rDNA, all rhizomorphs sampled from the stumps and logs were of Armillaria ostoyae. The size of the genets was estimated with random amplified microsatellites analysis of the isolates and ranged from single stumps to approximately 450m(2). One to seven genets were found in each stand. These results indicate that the genets had arisen from spores and vegetative spread was limited on most sites.Öğe Boxwood Blight in Turkey: Impact on Natural Boxwood Populations and Management Challenges(Inst Forestry Lrcaf, 2017) Lehtijaervi, Asko Tapio; Dogmus-Lehtijarvi, H. Tugba; Oskay, FundaThere are approximately 1000 ha of natural populations of Buxus sempervirens, a small evergreen tree widely used in ornamental landscaping, in Turkey. These populations usually occur as an understorey in forests. Since the outbreak of boxwood blight epidemics in the Eastern Black Sea region in 2011 approximately 90% of the trees in the affected areas have died. In this paper we discuss the possibilities to save boxwood in Turkey.Öğe Ceratocystis platani is killing plane trees in Istanbul (Turkey)(Wiley, 2018) Lehtijaervi, Asko Tapio; Oskay, F.; Lehtijarvi, H. T. Dogmus; Kaya, A. G. Aday; Pecori, F.; Santini, A.Ceratocystis platani was detected at several locations in the European side of Istanbul, causing severe dieback and mortality, mainly on Platanusxacerifolia imported from Italy approximately 160years ago, but also on Platanus orientalis. In the work reported here, the causal agent of the dieback and mortality was identified based on morphological characteristics in culture and internal transcribed spacer (ITS) sequencing, confirming the presence of C.platani in Turkey. All analysed C.platani isolates from Istanbul shared the same ITS sequence with European C.platani strains available in the NCBI, but differed from other species previously ascribed to the Ceratocystis fimbriata species complex. Pathogenicity of C.platani was proven by inoculation onto 25-cm-long and 4-9mm diam. P.orientalis twigs and the causal agent reisolated from symptomatic tissues. In a survey of 976 Platanus in streets and parks of Istanbul, 26.5% of trees showed symptoms of C.platani infections, whilst 5.6% were dead. The proportion of symptomatic trees was higher where management interventions, such as topping or pruning and felling infected trees had been carried out.Öğe Cryptic Risks to Forest Biosecurity Associated with the Global Movement of Commercial Seed(Mdpi, 2019) Cleary, Michelle; Oskay, Funda; Dogmus, Hatice Tugba; Lehtijaervi, Asko Tapio; Woodward, Stephen; Vettraino, Anna MariaThe import and export of tree seed carries with it risks of inadvertent introduction of pests and pathogens to hitherto unaffected regions. Although trade in seed of specified trees is regulated, phytosanitary requirements for most tree species are minimal, even those related to the most important forest tree species in a given region. A better understanding of the microbiome associated with seed intended for commercial production or ornamental use, and their potential risk with the transport from the source origin of distributors, will help regulatory agencies implement measures to safeguard seed health and avoid trade-related spread of potentially harmful pathogens. In this study we used high-throughput sequencing to show that highly diverse fungal communities were associated with seed of 14 different Pinus species obtained from seed banks (seed orchards) and retail sources (online distributors) in North America and Europe. Fungal diversity differed among the 23 seedlots tested. Community composition did not relate to the species of Pinus nor the country of origin. Assigned potential functions based on sequence identity using FUNGuild provided an overall understanding of the likely life strategies of fungal operational taxonomic units (OTUs). Of those sequences classified to a trophic level, 453 were plant pathogens, with the Dothideomycetes having the highest prevalence. The most common plant pathogens included Sydowia polyspora, Lasiodiplodia theobromae, Diplodia intermedia and Diplodia sapinea that were detected from the majority of Pinus species. The evidence presented here illustrates an urgent need for plant protection authorities, practitioners and the general public to recognize the potential risk of introducing harmful pathogens through innocent transport of seed.Öğe Cylindrocladium buxicola is Threatening the Native Buxus sempervirens Populations in Turkey - Short Communication(Czech Academy Agricultural Sciences, 2014) Lehtijaervi, Asko Tapio; Dogmus-Lehtijarvi, H. Tugba; Oskay, FundaCylindrocladium buxicola is a fungal pathogen of Buxus spp. in Turkey; the pathogen was first noted in 2011 on the native populations of B. sempervirens in forests in Trabzon in the Black Sea region. Surveys conducted in November 2012 revealed a devastating impact of the pathogen on natural B. sempervirens populations, in which the trees were either dead or severely defoliated. The epidemic had spread 3-25 km along the river valleys near the Black Sea coast. Similar river valleys further inland were still free of infection or showed only the very first signs of arrival of the epidemic. The disease has recently been found also in nurseries. All isolates tested belonged to the G1 clade.Öğe Damage to roots and collars of broadleaf woody plants(Cabi Publishing-C A B Int, 2017) Glavendekic, M.; Matsiakh, I.; Lakatos, F.; Csoka, G.; Moreira, A. C.; Lehtijaervi, Asko Tapio[No Abstract Available]Öğe Damage to roots and collars of coniferous woody plants(Cabi Publishing-C A B Int, 2017) Glavendekic, M.; Matsiakh, I.; Lakatos, F.; Csoka, G.; Moreira, A. C.; Lehtijaervi, Asko Tapio[No Abstract Available]Öğe Diplodia Tip Blight on Its Way to the North: Drivers of Disease Emergence in Northern Europe(Frontiers Media Sa, 2019) Brodde, Laura; Adamson, Kalev; Julio Camarero, J.; Castano, Carles; Drenkhan, Rein; Lehtijaervi, Asko TapioDisease emergence in northern and boreal forests has been mostly due to tree-pathogen encounters lacking a co-evolutionary past. However, outbreaks involving novel interactions of the host or the pathogen with the environment have been less well documented. Following an increase of records in Northern Europe, the first large outbreak of Diplodia sapinea on Pinus sylvastris was discovered in Sweden in 2016. By reconstructing the development of the epidemic, we found that the attacks started approx. 10 years back from several isolated trees in the stand and ended up affecting almost 90% of the trees in 2016. Limited damage was observed in other plantations in the surroundings of the affected stand, pointing to a new introduced pathogen as the cause of the outbreak. Nevertheless, no genetic differences based on SSR markers were found between isolates of the outbreak area and other Swedish isolates predating the outbreak or from other populations in Europe and Asia Minor. On a temporal scale, we saw that warm May and June temperatures were associated with higher damage and low tree growth, while cold and rainy conditions seemed to favor growth and deter disease. At a spatial scale, we saw that spread occurred predominantly in the SW aspect-area of the stand. Within that area and based on tree-ring and isotope (delta C-13) analyses, we saw that disease occurred on trees that over the years had shown a lower water-use efficiency (WUE). Spore traps showed that highly infected trees were those producing the largest amount of inoculum. D. sapinea impaired latewood growth and reduced C reserves in needles and branches. D. sapinea attacks can cause serious economic damage by killing new shoots, disrupting the crown, and affecting the quality of stems. Our results show that D. sapinea has no limitations in becoming a serious pathogen in Northern Europe. Management should focus on reducing inoculum, especially since climate change may bring more favorable conditions for this pathogen. Seedlings for planting should be carefully inspected as D. sapinea may be present in a latent stage in asymptomatic tissues.Öğe First Report of Diplodia pinea on Pseudotsuga menziesii in Turkey(Amer Phytopathological Soc, 2014) Kaya, A. G. A.; Lehtijaervi, Asko Tapio; Kaya, O.; Dogmus-Lehtijarvi, T.Öğe First report of Diplodia sapinea on Cedrus libani in Turkey(John Wiley and Sons Inc, 2018) Oskay F.; Lehtijaervi, Asko Tapio; Dogmuş-Lehtijärvi H.T.; Woodward S.Cedar of Lebanon (Cedrus libani) is an ecologically and economically important conifer with a natural distribution in southern Turkey. Currently, no serious diseases affect C. libani in its native range, although it is susceptible to pathogens such as Heterobasidion annosum and Diplodia pinea in inoculation experiments (Lehtijärvi et al., 1). Recent reports from the Balkans and Northern Europe, however, suggest that C. libani is susceptible to foliage and shoot diseases such as Diplodia pinea, Dothistroma septosporum and Sirococcus tsugae (Mullet et al., 2; Zlatkovic et al., 2016).Öğe First Report of Phytophthora syringae on Cedrus libani in Turkey(Amer Phytopathological Soc, 2014) Dogmus-Lehtijarvi, T.; Kaya, A. G. Aday; Lehtijaervi, Asko Tapio; Jung, T.Cedrus libani, commonly known as Lebanon cedar, is one of the most important coniferous tree species in Turkey. Its main distribution is in the Taurus Mountains in the Mediterranean Region. The total area of pure Taurus cedar forest covers 109,440 ha in Turkey, all located in the southwestern regions of the country. Due to its drought resistance, Taurus cedar has been commonly used for afforestations in these semi-arid areas (1). In September 2011, during surveys for Phytophthora spp. in forest nurseries in Adapazari and İzmir in eastern Turkey, initial symptoms such as death of fine roots, yellowing, and wilting of Taurus cedar seedlings were observed. Soil samples were collected from 10 symptomatic C. libani seedlings and isolation tests for Phytophthora species were carried out using leaflets from young Quercus suber, Azalea sp., and Rhodendron sp. saplings as baits floated over flooded soil. Necrotic baits were blotted dry, cut into small pieces, and placed on selective PARPNH carrot agar. Out growing colonies were subcultured on carrot agar and kept at 12°C for morphological and molecular identifications (2). In total, six Pythiaceous isolates were obtained from the C. libani soil samples. The isolates were investigated using a light microscope and grouped according to their morphological characteristics (3). DNA was extracted from two representative isolates using Qiagen DNeasy Plant Mini Kit following the manufacturer's instructions. PCR amplifications and sequencing of the internal transcribed spacer (ITS) region of rDNA and the β-tubulin gene were performed using ITS1 and ITS4 and Tub1 and Tub2 primer sets (4). Sequencing of the PCR products in both directions was conducted by IonTek Inc. (Istanbul, Turkey) in an ABI PRISM automated sequencer. The obtained sequences were compared with those in the GenBank and Phytophthora database using BLAST search. On the basis of morphological features and molecular analyses, the two isolates were identified as Phytophthora syringae. Morphological characteristics on carrot agar were identical with the description of P. syringae (2). At 20°C, colonies reached 7 cm in diameter after 1 week. Sporangia were semipapillate to non-papillate, ovoid, with average length of 59 μm (SD ± 2.8) (range 58 to 70 μm). Oogonia were 38 μm (SD ± 5.4) in diameter (range 30 to 47 μm) with paragynous antheridia. The morphological identification was confirmed by sequence comparison at GenBank with 99% homology for both ITS and β-tubulin. The ITS sequences of the two isolates were deposited in GenBank with the accession nos. KF430614 and KF944377. Under-bark inoculation tests with mycelia plugs were conducted with both isolates of P. syringae at 18°C in a growth chamber on a total of six 1-year-old shoots cut from two C. libani trees. Lesions with an average length of 19 mm (SD ± 6) developed after 10 days. P. syringae was consistently re-isolated from the margins of necrotic tissues. Control shoots remained symptomless. To our knowledge, this is the first report of damage caused by P. syringae on C. libani seedlings in forest nursery in Turkey.Öğe From leaf to continent: The multi-scale distribution of an invasive cryptic pathogen complex on oak(Elsevier Sci Ltd, 2018) Desprez-Loustau, Marie-Laure; Massot, Marie; Toigo, Maude; Fort, Tania; Kaya, Ayse Gulden Aday; Lehtijaervi, Asko TapioThe spatial distribution and niche differentiation of three closely related species (Erysiphe alphitoides, Erysiphe quercicola and Erysiphe hypophylla) causing oak powdery mildew was studied at scales ranging from the European continent, where they are invasive, to a single leaf. While E. alphitoides was dominant at all scales, E. quercicola and E. hypophylla had restricted geographic, stand and leaf distributions. The large-scale distributions were likely explained by climatic factors and species environmental tolerances, with E. quercicola being more frequent in warmer climates and E. hypophylla in colder climates. The extensive sampling and molecular analyses revealed the cryptic invasion of E. quercicola in nine countries from which it had not previously been recorded. The presence of the three species was also strongly affected by host factors, such as oak species and developmental stage. Segregation patterns between Erysiphe species were observed at the leaf scale, between and within leaf surfaces, suggesting competitive effects. (C) 2018 Elsevier Ltd and British Mycological Society. All rights reserved.Öğe Global geographic distribution and host range of Dothistroma species: a comprehensive review(Wiley, 2016) Drenkhan, R.; Tomesova-Haataja, V.; Fraser, S.; Bradshaw, R. E.; Vahalik, P.; Lehtijaervi, Asko TapioDothistroma 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 the published results of provenance trials; and (v) to consider the effects of site factors on disease incidence and severity. The review shows that DNB occurs in 76 countries, with D. septosporum confirmed to occur in 44 and D. pini in 13. There are now 109 documented Pinaceae host taxa for Dothistroma species, spanning six genera (Abies, Cedrus, Larix, Picea, Pinus and Pseudotsuga), with Pinus being the dominant host genus, accounting for 95 host taxa. The relative susceptibilities of these hosts to Dothistroma species are reported, providing a resource to inform species choice in forest planting. Country records show that most DNB outbreaks in Europe occur on Pinus nigra and its subspecies. It is anticipated that the collaborative work described in this review will both underpin a broader global research strategy to manage DNB in the future and provide a model for the study of other forest pathogens.Öğe Heterobasidion Infection in Abies nordmanniana ssp. bornmülleriana Stands in Kastamonu Province(2012) Lehtijaervi, Asko Tapio; Lehtijarvi, H. T. Doğmuş; Ünal, S.; Karadeniz, M.; Aday, A. G. Kaya; Oskay, F.In this study, the proportion of Abies bornmülleriana trees infected by Heterobasidion spp. was investigated in Kastamonu Province in different types of stands. One 1 cm-thick disc was taken from each of 100 freshly cut trees, washed under a running tap, placed into plastic bags and incubated in growth chamber at 24 C° for 7 days. The area occupied by the conidial stage of Heterobasidion annosum s.l. was determined under a stereomicroscope using transparent film placed onto the upper surface of each disc. During this investigation conidia of Heterobasidion annosum s.l. were taken with a needle and placed onto agar plates. The obtained isolates were identified with pairing tests and DNA-based methods. All 36 isolates responded as Heterobasidion abietinum to the tester isolates. Identification based on PCR amplification with MJF – MJR and KJF-KFR primers gave the same result. 34% (34 out of 100) of the discs taken from the fir forests were found to be infected with H. abietinum. The characteristics of the colonized patches on the discs indicated that the H. abietinum colonies originated from stem infections of the trees. The proportion of the disc area covered by the conidial stage of the fungus was 80% in one of the discs, 6-10% in 6 discs, 1-5% in 18 discs, and 0-1 % in 11 discs. The conidiophores were observed in heartwood in only five samples.Öğe Identifying the ecological and societal consequences of a decline in Buxus forests in Europe and the Caucasus(Springer, 2018) Mitchell, Ruth; Chitanava, Savely; Dbar, Roman; Kramarets, Volodymyr; Lehtijaervi, Asko Tapio; Matchutadze, IzoldaThe potential impact of new invasive tree pests and diseases is usually quantified in economic terms. The ecological and social impacts are less often assessed. Using a comprehensive literature review we assess the potential ecological and social impact of two non-native invasive species (the box tree moth, Cydalima perspectalis and the fungus Calonectria pseudonaviculata) that threaten the survival of box tree, Buxus spp. in forests in Europe and the Caucasus. A total of 132 fungi, 12 chromista (algae), 98 invertebrate and 44 lichens were found to use Buxus spp. Of these, 43 fungi, 3 chromista and 18 invertebrate species have only been recorded on Buxus spp., suggesting that these species are obligate on Buxus spp. and are most at risk from in the loss of Buxus spp. due to these invasive pest and disease species. Buxus spp. was shown to be important for soil stability and water quality but there was no information on other ecosystem functions provided by Buxus spp. Buxus was found to be of considerable historical cultural importance but there was very limited information on current social values and uses. Buxus trees, wood and leaves are associated with different folklore and sacred rites which are still particularly important in the Caucasus. While we could not find any assessment of the economic value of Buxus forests the biodiversity, cultural and social values of Buxus identified here indicate that its loss could have major indirect and non-market economic effects. This work highlights the importance of studying the ecological and societal implications of biological invasions.Öğe Impacts of inoculation with Herpotrichia pinetorum, Gremmenia infestans and Gremmeniella abietina on Pinus nigra subsp pallasiana and Cedrus libani seedlings in the field(Wiley, 2016) Dogmus-Lehtijarvi, H. T.; Lehtijaervi, Asko Tapio; Woodward, S.; Oskay, F.Herpotrichia pinetorum, Gremmenia infestans and Gremmeniella abietina were inoculated onto 2-year-old Anatolian black pine (Pinus nigra subsp. pallasiana) and Taurus cedar (Cedrus libani) seedlings planted in a high mountain forest (1800m a.s.l) in south-western Turkey, to determine the effects of these fungi during winter. In June, 8months after inoculation, 39.9% of experimental plants were dead and 20.4% of the surviving plants failed to flush. Gremmeniella abietina and H.pinetorum caused the most fatalities. Prevention of new shoot formation on surviving plants, however, was mainly an effect of G.abietina infections, although many surviving plants inoculated with G.infestans or H.pinetorum also failed to flush. All three pathogens had the potential to severely damage young plants of P.nigra subsp. pallasiana and C.libani growing at high elevations near to forests with heavy inoculum loads. The implications of this finding for P.nigra afforestations at high altitudes in Turkey are discussed. This study is also the first to report that G.infestans can infect and cause disease on young C.libani plants.Öğe Mikovirüslerin orman patojenlerine karşı kullanım olanakları(2015) Kaya, Ayşe Gülden Aday; Lehtijarvi, Hatice Tuğba Doğmuş; Lehtijaervi, Asko TapioMikovirüsler bitki patojeni funguslarının da bulunduğu birçok organizmada yaygın olarak bulunan obligat parazitlerdir. Eşeyli ve ya eşeysiz fungal yapılar sayesinde hücreler arası yayılış göstermekte ve konukçularında bazı değişikliklere neden olmaktadırlar. Mikovirüslerin konukçularında neden olduğu değişiklikler tam anlamıyla bilinmemekteyse de, enfekte ettikleri funguslarda bazı fenotipik değişimlere yol açtığı düşünülmektedir. Özellikle, bitki patojeni fungusların virülensi arttırma ya da azaltma yönünde üzerine etkide bulunmaktadırlar. Virulensi azaltmaları durumunda, kestane kanseri örneğinde olduğu gibi, mikovirüslerin biyolojik mücadelede kullanmak mümkün olabilmektedir. Bu derlemede, dünyada ve ülkemizde orman ağaçlarında hastalığa neden olan bazı önemli fungal patojenlerde görülen mikovirüsler tanıtılarak, bunların biyolojik mücadelede kullanım olanakları üzerine yapılan araştırmalar özetlenmiştir.Öğe Occurrence and Genetic Similarity of Diplodia pinea on Shoots and Cones in Seed Orchards of Pinus spp. in North-Western Turkey(Czech Academy Agricultural Sciences, 2014) Dogmus-Lehtijarvi, Tugba H.; Kaya, Ayse Gulden Aday; Lehtijaervi, Asko Tapio; Oskay, Funda; Kaya, Ozgur DurmusDiplodia shoot blight disease can cause significant damage on coniferous trees and be particularly injurious to cones, which reduces the amount of seed production and germination. We investigated the disease severity and genetic variation of Diplodia pinea in one Pinus nigra and two P. sylvestris seed orchards. Disease surveys were carried out in Izmit (Marmara region, Turkey) in May 2012. Symptomatic shoots and cones were examined for the presence of pycnidia. Cultural and morphological characteristics of the isolates were studied using cultures grown on potato dextrose agar (PDA). Based on morphological characteristics and results using species specific primers, the pycnidia on shoots and cones were identified as D. pinea. In addition, Random Amplified Microsatellite Sequence (RAMS) analyses indicated that there was a single genet of D. pinea which caused the disease in the seed orchards. All of the 60 sampled trees were found to be infected by the fungus. There were differences in disease severity among the stands.Öğe Oomycota species associated with deciduous and coniferous seedlings in forest tree nurseries of Western Turkey(Wiley, 2017) Lehtijaervi, Asko Tapio; Kaya, A. G. Aday; Woodward, S.; Jung, T.; Lehtijarvi, H. T. DogmusOccurrence and pathogenicity of Oomycota species causing root rot were investigated in 10 forest tree nurseries in western Turkey. Soil samples (129 in total) taken from the rhizosphere of symptomatic seedlings were baited for Oomycota using young leaves of Quercus suber, Rhododendron simsii and R.ponticum. Oomycota (178 isolates) were obtained by culturing on selective media, and identified using morphological methods followed by PCR and sequencing of the ITS rDNA and cox1 regions. Phytophthora aff. cactorum, P.citricola sensu lato, P.crassamura, P.syringae, Pythium aphanidermatum, Py.intermedium, Py.irregulare, Py.ultimum and Phytopythium vexans were common amongst the isolates. The highest diversity of Oomycota was found in the forest nurseries at Adapazar-Hendek and zmir-Torbal. Pathogenicity tests showed that the isolates caused lesions on a range of host plants. The importance of these nursery infections in transferring potentially damaging oomycete species to Turkish forests is discussed.Öğe Pathogenicity of Heterobasidion annosum (Fr.) Bref. sensu stricto on coniferous tree species in Turkey(Wiley-Blackwell, 2016) Dogmus-Lehtijarvi, H. T.; Erdogan, R. C.; Lehtijaervi, Asko Tapio; Woodward, S.; Kaya, A. G. AdayTwo-year-old seedlings of Pinus brutia, P.brutia var. eldarica, Pinus pinea and 3-year-old seedlings of Pinus radiata, Pinus sylvestris, Pinus nigra and Cedrus libani were inoculated on the lower stem with isolates of Heterobasidion annosum s.s. collected from the Black Sea and Mediterranean regions of Turkey. In total, 315 seedlings were inoculated in April 2014 and incubated in a growth chamber for 7weeks at 18-20 degrees C. All isolates were pathogenic on the seven different hosts and had the ability to grow in living sapwood. The isolates had a greater growth on C.libani, P. sylvestris and P.radiata seedlings compared to plants of the other species tested. The least affected species were P.brutia and P. nigra. The isolates originating from the Black Sea region caused longer lesions on the hosts. Overall mortality during 7weeks of incubation was 4%.
