First report of Lecanosticta acicola on pine and non-pine hosts in Turkey

Acknowledgements We would like to thank İstanbul Bahçeköy Forestry Enterprise for allowing us to sample in the Arboretum, and to Merve Kartaloğlu Sönmez the manager of the Arboretum, for her hospitality. This study was partly supported by the Estonian Science Foundation grant PSG136, the Ministry of Rural Affairs of Estonia, and the Euphresco projects; Lecanosticta - Brown spot disease of pines – spread in European forest ecosystems: impact on pines, predisposing and contributing factors, control (BROWNSPOTRISK) and the International Plant Sentinel Network as an early warning system; research on future pest threats (IPSN II).Peer reviewedPostprin

Phenotypical and molecular characterisation of Fusarium circinatum: correlation with virulence and fungicide sensitivity

[EN] Fusarium circinatum, causing pine pitch canker, is one of the most damaging pathogens of Pinus species. This study investigated the use of phenotypical and molecular characteristics to delineate groups in a worldwide collection of isolates. The groups correlated with virulence and fungicide sensitivity, which were tested in a subset of isolates. Virulence tests of twenty isolates on P. radiata, P. sylvestris and P. pinaster demonstrated differences in host susceptibility, with P. radiata most susceptible and P. sylvestris least susceptible. Sensitivity to the fungicides fludioxonil and pyraclostrobin varied considerably between isolates from highly effective (half-maximal effective concentration (EC50) 100 ppm). This study demonstrates the potential use of simply acquired phenotypical (cultural, morphological) and molecular metrics to gain a preliminary estimate of virulence and sensitivity to certain fungicides. It also highlights the necessity of including a range of isolates in fungicide tests and host susceptibility assays, particularly of relevance to tree breeding programmes.M.B. was a contract holder of Campus de Excelencia Internacional-UPV programme. This work was partially funded by PROTREE, a project funded jointly by a grant from BBSRC, Defra, ESRC, the Forestry Commission, NERC and the Scottish Government, under the Tree Health and Plant Biosecurity Initiative, grant number BB/L012243/1. Additional funding and networking support was provided by the PINESTRENGTH COST Action (FP1406).Mullett, M.; Pérez Sierra, AM.; Armengol Fortí, J.; Berbegal Martinez, M. (2017). Phenotypical and molecular characterisation of Fusarium circinatum: correlation with virulence and fungicide sensitivity. Forests. 8(11):1-22. https://doi.org/10.3390/f8110458S122811Martín-Rodrigues, N., Espinel, S., Sanchez-Zabala, J., Ortíz, A., González-Murua, C., & Duñabeitia, M. K. (2013). Spatial and temporal dynamics of the colonization ofPinus radiatabyFusarium circinatum, of conidiophora development in the pith and of traumatic resin duct formation. New Phytologist, 198(4), 1215-1227. doi:10.1111/nph.12222Wingfield, M. J., Hammerbacher, A., Ganley, R. J., Steenkamp, E. T., Gordon, T. R., Wingfield, B. D., & Coutinho, T. A. (2008). Pitch canker caused byFusarium circinatum– a growing threat to pine plantations and forests worldwide. Australasian Plant Pathology, 37(4), 319. doi:10.1071/ap08036Dwinell, L. D. (1985). Pitch Canker: A Disease Complex of Southern Pines. Plant Disease, 69(3), 270. doi:10.1094/pd-69-270VILJOEN, A. (1994). First Reportof Fusarium subglutinansf.sp. pinion Pine Seedlings in South Africa. Plant Disease, 78(3), 309. doi:10.1094/pd-78-0309Fusarium circinatum (GIBBCI)https://gd.eppo.int/taxon/GIBBCI/distributionLanderas, E., García, P., Fernández, Y., Braña, M., Fernández-Alonso, O., Méndez-Lodos, S., … Armengol, J. (2005). Outbreak of Pitch Canker Caused by Fusarium circinatum on Pinus spp. in Northern Spain. Plant Disease, 89(9), 1015-1015. doi:10.1094/pd-89-1015aPérez-Sierra, A., Landeras, E., León, M., Berbegal, M., García-Jiménez, J., & Armengol, J. (2007). Characterization of Fusarium circinatum from Pinus spp. in northern Spain. Mycological Research, 111(7), 832-839. doi:10.1016/j.mycres.2007.05.009Carlucci, A., Colatruglio, L., & Frisullo, S. (2007). First Report of Pitch Canker Caused by Fusarium circinatum on Pinus halepensis and P. pinea in Apulia (Southern Italy). Plant Disease, 91(12), 1683-1683. doi:10.1094/pdis-91-12-1683cBragança, H., Diogo, E., Moniz, F., & Amaro, P. (2009). First Report of Pitch Canker on Pines Caused by Fusarium circinatum in Portugal. Plant Disease, 93(10), 1079-1079. doi:10.1094/pdis-93-10-1079aEPPO PQR—EPPO Database on Quarantine Pestshttp://www.eppo.intBerbegal, M., Pérez-Sierra, A., Armengol, J., & Grünwald, N. J. (2013). Evidence for Multiple Introductions and Clonality in Spanish Populations of Fusarium circinatum. Phytopathology®, 103(8), 851-861. doi:10.1094/phyto-11-12-0281-rGordon, T. R., Okamoto, D., Storer, A. J., & Wood, D. L. (1998). Susceptibility of Five Landscape Pines to Pitch Canker Disease, Caused by Fusarium subglutinans f. sp. pini. HortScience, 33(5), 868-871. doi:10.21273/hortsci.33.5.868Hodge, G. R., & Dvorak, W. S. (2000). New Forests, 19(3), 241-258. doi:10.1023/a:1006613021996Roux, J., Eisenberg, B., Kanzler, A., Nel, A., Coetzee, V., Kietzka, E., & Wingfield, M. J. (2006). Testing of selected South African Pinus hybrids and families for tolerance to the pitch canker pathogen, Fusarium circinatum. New Forests, 33(2), 109-123. doi:10.1007/s11056-006-9017-4Iturritxa, E., Mesanza, N., Elvira-Recuenco, M., Serrano, Y., Quintana, E., & Raposo, R. (2012). Evaluation of genetic resistance in Pinus to pitch canker in Spain. Australasian Plant Pathology, 41(6), 601-607. doi:10.1007/s13313-012-0160-4Martínez-Álvarez, P., Pando, V., & Diez, J. J. (2014). Alternative species to replace Monterey pine plantations affected by pitch canker caused byFusarium circinatumin northern Spain. Plant Pathology, 63(5), 1086-1094. doi:10.1111/ppa.12187Schmale, D. G., & Gordon, T. R. (2003). Variation in susceptibility to pitch canker disease, caused by Fusarium circinatum, in native stands of Pinus muricata. Plant Pathology, 52(6), 720-725. doi:10.1111/j.1365-3059.2003.00925.xKuhlman, E. G. (1985). Pitch Canker Disease of Loblolly and Pond Pines in North Carolina Plantations. Plant Disease, 69(2), 175. doi:10.1094/pd-69-175Elvira-Recuenco, M., Iturritxa, E., Majada, J., Alia, R., & Raposo, R. (2014). Adaptive Potential of Maritime Pine (Pinus pinaster) Populations to the Emerging Pitch Canker Pathogen, Fusarium circinatum. PLoS ONE, 9(12), e114971. doi:10.1371/journal.pone.0114971VILJOEN, A., WINGFIELD, M. J., KEMP, G. H. J., & MARASAS, W. F. O. (1995). Susceptibility of pines in South Africa to the pitch canker fungus subglutinans f.sp. pini. Plant Pathology, 44(5), 877-882. doi:10.1111/j.1365-3059.1995.tb02747.xMuñoz-Adalia, E. J., Flores-Pacheco, J. A., Martínez-Álvarez, P., Martín-García, J., Fernández, M., & Diez, J. J. (2016). Effect of mycoviruses on the virulence of Fusarium circinatum and laccase activity. Physiological and Molecular Plant Pathology, 94, 8-15. doi:10.1016/j.pmpp.2016.03.002Martínez-Álvarez, P., Vainio, E. J., Botella, L., Hantula, J., & Diez, J. J. (2014). Three mitovirus strains infecting a single isolate of Fusarium circinatum are the first putative members of the family Narnaviridae detected in a fungus of the genus Fusarium. Archives of Virology, 159(8), 2153-2155. doi:10.1007/s00705-014-2012-8Agusti-Brisach, C., Perez-Sierra, A., Armengol, J., Garcia-Jimenez, J., & Berbegal, M. (2012). Efficacy of hot water treatment to reduce the incidence of Fusarium circinatum on Pinus radiata seeds. Forestry, 85(5), 629-635. doi:10.1093/forestry/cps074Berbegal, M., Landeras, E., Sánchez, D., Abad-Campos, P., Pérez-Sierra, A., & Armengol, J. (2015). Evaluation ofPinus radiataseed treatments to controlFusarium circinatum: effects on seed emergence and disease incidence. Forest Pathology, 45(6), 525-533. doi:10.1111/efp.12204Van Poucke, K., Franceschini, S., Webber, J. F., Vercauteren, A., Turner, J. A., McCracken, A. R., … Brasier, C. M. (2012). Discovery of a fourth evolutionary lineage of Phytophthora ramorum: EU2. Fungal Biology, 116(11), 1178-1191. doi:10.1016/j.funbio.2012.09.003Brasier, C. M., Franceschini, S., Vettraino, A. M., Hansen, E. M., Green, S., Robin, C., … Vannini, A. (2012). Four phenotypically and phylogenetically distinct lineages in Phytophthora lateralis. Fungal Biology, 116(12), 1232-1249. doi:10.1016/j.funbio.2012.10.002Franceschini, S., Webber, J. F., Sancisi-Frey, S., & Brasier, C. M. (2013). Gene × environment tests discriminate the new EU2 evolutionary lineage ofPhytophthora ramorumand indicate that it is adaptively different. Forest Pathology, 44(3), 219-232. doi:10.1111/efp.12085Robin, C., Brasier, C., Reeser, P., Sutton, W., Vannini, A., Vettraino, A. M., & Hansen, E. (2015). Pathogenicity of Phytophthora lateralis Lineages on Different Selections of Chamaecyparis lawsoniana. Plant Disease, 99(8), 1133-1139. doi:10.1094/pdis-07-14-0720-reAgricolae: Statistical Procedures for Agricultural Researchhttp://tarwi.lamolina.edu.pe/~fmendiburuLê, S., Josse, J., & Husson, F. (2008). FactoMineR: AnRPackage for Multivariate Analysis. Journal of Statistical Software, 25(1). doi:10.18637/jss.v025.i01Bates, D., Mächler, M., Bolker, B., & Walker, S. (2015). Fitting Linear Mixed-Effects Models Usinglme4. Journal of Statistical Software, 67(1). doi:10.18637/jss.v067.i01Kim, Y.-S., Woo, K.-S., Koo, Y.-B., & Yeo, J.-K. (2008). Variation in susceptibility of six pine species and hybrids to pitch canker caused byFusarium  circinatum. Forest Pathology, 38(6), 419-428. doi:10.1111/j.1439-0329.2008.00558.xRunion, G. B. (1988). Effects of Thiabendazole-DMSO Treatment of Longleaf Pine Seed Contaminated with Fusarium subglutinans on Germination and Seedling Survival. Plant Disease, 72(10), 872. doi:10.1094/pd-72-0872Allen, T. ., Enebak, S. ., & Carey, W. . (2004). Evaluation of fungicides for control of species of Fusarium on longleaf pine seed. Crop Protection, 23(10), 979-982. doi:10.1016/j.cropro.2004.02.010Chung, W.-H., Ishii, H., Nishimura, K., Fukaya, M., Yano, K., & Kajitani, Y. (2006). Fungicide Sensitivity and Phylogenetic Relationship of Anthracnose Fungi Isolated from Various Fruit Crops in Japan. Plant Disease, 90(4), 506-512. doi:10.1094/pd-90-0506Secor, G. A., Rivera, V. V., Khan, M. F. R., & Gudmestad, N. C. (2010). Monitoring Fungicide Sensitivity of Cercospora beticola of Sugar Beet for Disease Management Decisions. Plant Disease, 94(11), 1272-1282. doi:10.1094/pdis-07-09-0471Nirenberg, H. I., & O’Donnell, K. (1998). New Fusarium Species and Combinations within the Gibberella fujikuroi Species Complex. Mycologia, 90(3), 434. doi:10.2307/3761403Inman, A. R., Kirkpatrick, S. C., Gordon, T. R., & Shaw, D. V. (2008). Limiting Effects of Low Temperature on Growth and Spore Germination in Gibberella circinata, the Cause of Pitch Canker in Pine Species. Plant Disease, 92(4), 542-545. doi:10.1094/pdis-92-4-054

Multilocus sequence typing provides insights into the population structure and evolutionary potential of Brenneria goodwinii, associated with acute oak decline

Brenneria goodwinii is one of the most frequently isolated Gram-negative bacteria from native oak species, Quercus robur and Q. petraea, affected by acute oak decline (AOD) in the UK. We investigated the population biology of this bacterial species using a multilocus sequence analysis to determine the population structure and evolutionary potential. Seven partial housekeeping genes were used in the analyses. Amongst 44 bacterial strains from seven different locations, we identified 22 unique sequence types [STs]; only one ST was found at two separate locations. Phylogenetic and cluster-based analyses suggested that B. goodwinii STs form two main distinct groups; however, no geographical pattern of their distribution could be observed. Clonality and recombination tests demonstrated that the studied population is primarily clonal, however both mutation and recombination processes play a role in shaping the genetic structure and evolution of the population. Our study suggests that the B. goodwinii population on oak in the UK has an endemic form, with background recombination appearing to generate new alleles more frequently than mutation, despite the introduction of nucleotide substitutions being approximately twice less likely than mutation. The newly emerged STs subsequently undergo clonal expansion to become dominant genotypes within their specific geographical locations and even within the individual host oak trees

Population structure and diversity of the needle pathogen Dothistroma pini suggests human-mediated movement in Europe

Dothistroma needle blight (DNB) is an important disease of Pinus species that can be caused by one of two distinct but closely related pathogens; Dothistroma septosporum and Dothistroma pini. Dothistroma septosporum has a wide geographic distribution and is relatively well-known. In contrast, D. pini is known only from the United States and Europe, and there is a distinct lack of knowledge regarding its population structure and genetic diversity. The recent development of 16 microsatellite markers for D. pini provided an opportunity to investigate the diversity, structure, and mode of reproduction for populations collected over a period of 12 years, on eight different hosts in Europe. In total, 345 isolates from Belgium, the Czech Republic, France, Hungary, Romania, Western Russia, Serbia, Slovakia, Slovenia, Spain, Switzerland, and Ukraine were screened using microsatellite and species-specific mating type markers. A total of 109 unique multilocus haplotypes were identified and structure analyses suggested that the populations are influenced by location rather than host species. Populations from France and Spain displayed the highest levels of genetic diversity followed by the population in Ukraine. Both mating types were detected in most countries, with the exception of Hungary, Russia and Slovenia. Evidence for sexual recombination was supported only in the population from Spain. The observed population structure and several shared haplotypes between non-bordering countries provides good evidence that the movement of D. pini in Europe has been strongly influenced by human activity in Europe

Phylogeography and population structure of the global, wide host-range hybrid pathogen Phytophthora × cambivora

Invasive, exotic plant pathogens pose a major threat to native and agricultural ecosystems. Phytophthora × cambivora is an invasive, destructive pathogen of forest and fruit trees causing severe damage worldwide to chestnuts ( Castanea ), apricots, peaches, plums, almonds and cherries ( Prunus ), apples ( Malus ), oaks ( Quercus ), and beech ( Fagus ). It was one of the first damaging invasive Phytophthora species to be introduced to Europe and North America, although its origin is unknown. We determined its population genetic history in Europe, North and South America, Australia and East Asia (mainly Japan) using genotyping-by-sequencing. Populations in Europe and Australia appear clonal, those in North America are highly clonal yet show some degree of sexual reproduction, and those in East Asia are partially sexual. Two clonal lineages, each of opposite mating type, and a hybrid lineage derived from these two lineages, dominated the populations in Europe and were predominantly found on fagaceous forest hosts ( Castanea , Quercus , Fagus ). Isolates from fruit trees ( Prunus and Malus ) belonged to a separate lineage found in Australia, North America, Europe and East Asia, indicating the disease on fruit trees could be caused by a distinct lineage of P. × cambivora , which may potentially be a separate sister species and has likely been moved with live plants . The highest genetic diversity was found in Japan, suggesting that East Asia is the centre of origin of the pathogen. Further surveys in unsampled, temperate regions of East Asia are needed to more precisely identify the location and range of the centre of diversity

Population structure and diversity of the needle pathogen Dothistroma pini suggests human-mediated movement in Europe

DATA AVAILABILITY STATEMENT : The authors acknowledge that the data presented in this study must be deposited and made publicly available in an acceptable repository, prior to publication. Frontiers cannot accept a manuscript that does not adhere to our open data policies.Dothistroma needle blight (DNB) is an important disease of Pinus species that can be caused by one of two distinct but closely related pathogens; Dothistroma septosporum and Dothistroma pini. Dothistroma septosporum has a wide geographic distribution and is relatively well-known. In contrast, D. pini is known only from the United States and Europe, and there is a distinct lack of knowledge regarding its population structure and genetic diversity. The recent development of 16 microsatellite markers for D. pini provided an opportunity to investigate the diversity, structure, and mode of reproduction for populations collected over a period of 12 years, on eight different hosts in Europe. In total, 345 isolates from Belgium, the Czech Republic, France, Hungary, Romania, Western Russia, Serbia, Slovakia, Slovenia, Spain, Switzerland, and Ukraine were screened using microsatellite and species-specific mating type markers. A total of 109 unique multilocus haplotypes were identified and structure analyses suggested that the populations are influenced by location rather than host species. Populations from France and Spain displayed the highest levels of genetic diversity followed by the population in Ukraine. Both mating types were detected in most countries, with the exception of Hungary, Russia and Slovenia. Evidence for sexual recombination was supported only in the population from Spain. The observed population structure and several shared haplotypes between non-bordering countries provides good evidence that the movement of D. pini in Europe has been strongly influenced by human activity in Europe.The University of Pretoria, members of the Tree Protection Cooperative Program (TPCP), the National Research Foundation, a Scarce Skills Doctoral Scholarship and DIAROD: EU COST Action FP1102 DIAROD.http://www.frontiersin.org/Geneticsam2024BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant PathologySDG-15:Life on lan

Diversity, migration routes, and worldwide population genetic structure of Lecanosticta acicola, the causal agent of brown spot needle blight

Lecanosticta acicola is a pine needle pathogen causing brown spot needle blight that results in premature needle shedding with considerable damage described in North America, Europe, and Asia. Microsatellite and mating type markers were used to study the population genetics, migration history, and reproduction mode of the pathogen, based on a collection of 650 isolates from 27 countries and 26 hosts across the range of L. acicola. The presence of L. acicola in Georgia was confirmed in this study. Migration analyses indicate there have been several introduction events from North America into Europe. However, some of the source populations still appear to remain unknown. The populations in Croatia and western Asia appear to originate from genetically similar populations in North America. Intercontinental movement of the pathogen was reflected in an identical haplotype occurring on two continents, in North America (Canada) and Europe (Germany). Several shared haplotypes between European populations further suggests more local pathogen movement between countries. Moreover, migration analyses indicate that the populations in northern Europe originate from more established populations in central Europe. Overall, the highest genetic diversity was observed in south-eastern USA. In Europe, the highest diversity was observed in France, where the presence of both known pathogen lineages was recorded. Less than half of the observed populations contained mating types in equal proportions. Although there is evidence of some sexual reproduction taking place, the pathogen spreads predominantly asexually and through anthropogenic activity

The increasing threat to European forests from the invasive foliar pine pathogen, Lecanosticta acicola

European forests are threatened by increasing numbers of invasive pests and pathogens. Over the past century, Lecanosticta acicola, a foliar pathogen predominantly of Pinus spp., has expanded its range globally, and is increasing in impact. Lecanosticta acicola causes brown spot needle blight, resulting in premature defoliation, reduced growth, and mortality in some hosts. Originating from southern regions of North American, it devastated forests in the USA's southern states in the early twentieth century, and in 1942 was discovered in Spain.Derived from Euphresco project 'Brownspotrisk,' this study aimed to establish the current distribution of Lecanosticta species, and assess the risks of L. acicola to European forests. Pathogen reports from the literature, and new/ unpublished survey data were combined into an open-access geo-database (http://www.portaloff orestpathology.com), and used to visualise the pathogen's range, infer its climatic tolerance, and update its host range. Lecanosticta species have now been recorded in 44 countries, mostly in the northern hemisphere. The type species, L. acicola, has increased its range in recent years, and is present in 24 out of the 26 European countries where data were available. Other species of Lecanosticta are largely restricted to Mexico and Central America, and recently Colombia.The geo-database records demonstrate that L. acicola tolerates a wide range of climates across the northern hemisphere, and indicate its potential to colonise Pinus spp. forests across large swathes of the Europe. Pre-liminary analyses suggest L. acicola could affect 62% of global Pinus species area by the end of this century, under climate change predictions.Although its host range appears slightly narrower than the similar Dothistroma species, Lecanosticta species were recorded on 70 host taxa, mostly Pinus spp., but including, Cedrus and Picea spp. Twenty-three, including species of critical ecological, environmental and economic significance in Europe, are highly susceptible to L. acicola, suffering heavy defoliation and sometimes mortality. Variation in apparent susceptibility between reports could reflect variation between regions in the hosts' genetic make-up, but could also reflect the signif-icant variation in L. acicola populations and lineages found across Europe. This study served to highlight sig-nificant gaps in our understanding of the pathogen's behaviour.Lecanosticta acicola has recently been downgraded from an A1 quarantine pest to a regulated non quarantine pathogen, and is now widely distributed across Europe. With a need to consider disease management, this study also explored global BSNB strategies, and used Case Studies to summarise the tactics employed to date in Europe