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 Pathogen reports from the literature, and new/ unpublished survey data were combined into an open-access geo-database (http://www.portaloff orestpathology.com), and used to visualise the pathogen's range, infer its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

Global Geographic Distribution and Host Range of Fusarium circinatum, the Causal Agent of Pine Pitch Canker

Fusarium circinatum, the causal agent of pine pitch canker (PPC), is currently one of the most important threats of Pinus spp. globally. This pathogen is known in many pine-growing regions, including natural and planted forests, and can affect all life stages of trees, from emerging seedlings to mature trees. Despite the importance of PPC, the global distribution of F. circinatum is poorly documented, and this problem is also true of the hosts within countries that are affected. The aim of this study was to review the global distribution of F. circinatum, with a particular focus on Europe. We considered (1) the current and historical pathogen records, both positive and negative, based on confirmed reports from Europe and globally; (2) the genetic diversity and population structure of the pathogen; (3) the current distribution of PPC in Europe, comparing published models of predicted disease distribution; and (4) host susceptibility by reviewing literature and generating a comprehensive list of known hosts for the fungus. These data were collated from 41 countries and used to compile a specially constructed geo-database. A review of 6297 observation records showed that F. circinatum and the symptoms it causes on conifers occurred in 14 countries, including four in Europe, and is absent in 28 countries. Field observations and experimental data from 138 host species revealed 106 susceptible host species including 85 Pinus species, 6 non-pine tree species and 15 grass and herb species. Our data confirm that susceptibility to F. circinatum varies between different host species, tree ages and environmental characteristics. Knowledge on the geographic distribution, host range and the relative susceptibility of different hosts is essential for disease management, mitigation and containment strategies. The findings reported in this review will support countries that are currently free of F. circinatum in implementing effective procedures and restrictions and prevent further spread of the pathogen

First report of 'Candidatus Phytoplasma mali' the causal agent of apple proliferation disease, in apple trees in Finland

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Emerging virus and viroid pathogen species identified for the first time in horticultural plants in Finland in 1997-2010

Expansion and intensification of global trade in horticultural plants has increased the risk of spread of new alien pathogen species in the EU. Alien species of pathogenic viruses and viroids in horticultural plants have been introduced into Finland in infected plant material (plants, seedlings, cuttings, tubers, seeds). By 1997, about 30 virus species of horticultural plants had been detected in Finland. We aimed at compiling emerging new virus and viroid records during 1997-2010. Eight new viruses belonging to tospo-, potex-, poty-, tymo-, ilar- and allexiviruses were detected in horticultural plants: four occurred in greenhouse crops, two in vegetables and two in garden ornamentals outdoors. Five new findings of viroids were made in ornamental and vegetable greenhouse crops during 2008-2009. More rapid and accurate diagnostic methods have contributed to identifying new alien pathogens. Global trade seems to be the main reason for the introduction of the newest virus and viroid pathogens into Finland.;Suomessa todetut kasvivirukset ja viroidit ovat pääosin kulkeutuneet maahamme ulkomailta tuodun kasviaineiston kuten kasvien, pistokkaiden, mukuloiden ja siementen mukana. Vuoteen 1997 mennessä oli raportoitu noin 30 Suomessa puutarhakasveista määritettyä virusta. Tutkimuksen tavoitteena oli tarkastella vuosina 1997-2010 puutarhakasveista määritettyjä viruksia ja viroideja. Kahdeksasta Suomessa määritetystä uudesta viruksesta neljä on todettu kasvihuonekasveista, kaksi vihanneskasveista avomaalta ja kaksi koristekasveista avomaalta. Viisi uutta viroidimääritystä on tehty vuosina 2008-2009 pääasiassa koristekasveista, mutta myös vihanneskasveista.Taudinaiheuttajien määritystä vaikeuttavat piilevät tartunnat sekä virusten esiintyminen epätasaisesti ja pieninä määrinä kasveissa. Toisaalta kasvintuhoojien määritysmenetelmät ovat kehittyneet viime vuosikymmeninä. Uudet määritysmenetelmät auttavat löytämään myös kasvitaudinaiheuttajia, jotka ovat oireettomia kyseisessä kasvissa, mutta voivat aiheuttaa sadonalennusta toisessa isäntäkasvissa kuten viroidit. Puutarhakasvien karanteenivirukset ja -viroidit on pystytty hävittämään kasvintarkastusviranomaisten toimesta, mutta lisääntynyt puutarhakasvien kansainvälinen kauppa tuo mukanaan uusia kasviviruksia ja viroideja Eurooppaan ja Suomeen

First report of Hop stunt viroid in greenhouse cucumber in Finland

v2011okpuj ks

Identity and potential pathogenicity o Phytophthora species found on symptomatic Rhododendron plants in a Finnish nursery

v2012okpka ks

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.portalofforestpathology.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. Preliminary 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 significant variation in L. acicola populations and lineages found across Europe. This study served to highlight significant 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