04 Vannini Presentazione Trabzon
Transcription
04 Vannini Presentazione Trabzon
COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Sentinel Trees as a Tool to Forecast Invasions of Alien Plant Pathogens Approach 1: PlosOne in Press AnnaMaria Vettraino 1, Alain Roques 2, Annie Yart 2, Jian-ting Fan3 , Jiang-hua Sun 4, Andrea Vannini1 1. DIBAF, University of Tuscia, Viterbo, Italy 2. INRA- UR633, Zoologie Forestière, Centre de recherche d'Orléans, Orléans, France 3. School of Forestry and Bio-technology, Zhejiang A & F University, Lin'an , China 4. State key laboratory of Integrated Management of pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing , China The increasing globalisation of trade in plants and plant material, together with the impacts of climate change, has led to an increase in the introduction and spread of new and damaging plant pathogens Number of Invasive Forest Pathogens in Europe the past 200 years Most of these species have been first described when already escaped from their centers of origin and begun causing damage in a susceptible plant community through host jump or hybridization From Santini et al., 2012 1 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Why do we fail in preventing introductions? Most of the National Plant Protection Organizations (NPPOs) regulate the inspections of living plants and commodities based on lists of known organisms described as invasive elsewhere (Lists of regulated quarantine and no-quarantine harmful organisms (e.g. the EPPO A1 and A2 list). These lists consider pathogens only after they have escaped from its geographic center of origin and begun causing damage in a susceptible plant community PRA protocols are developed on already escaped organisms and lack of data on their ecology, potential host range and adaptation Only a tiny proportion of imports is inspected (APHIS ~2%) Phytosanitary inspections in all EU countries don’t adhere to the same standard Why we fail in preventing introductions? Because most of the diagnostic protocols and inspections measures are directed to specific taxa (eg A1 and A2 listed organisms) As a consequence they may cover only a minority of the organisms which pose a threat………..around 10%? Basically they do not, or barely, consider the unknowns to science They did not allow for the existence of large numbers of high risk ‘unknown pathogens’ that, due to Darwinian co-evolution with their hosts, were causing little damage in their centres of origin Unknowns to science might enter unnoticed with their native hosts or in associated materials (eg soil, potting mix) with non-hosts 2 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Increase of invasions by IFP’s in the past 2 centuries 01/04/2015 Phytosanitary regulations and measures are flawed New strategies need to be employed in order to identify organisms harmful to European forests before their introduction Sentinel trees Network in its broad The concept of sense fully responds to this need In fact it responds to: • Approach 1 (pests & pathogens). The need of identify plant pathogens aggressive to EU species by establishing and monitoring sentinel plantations of selected (selection based on? WG1) EU plants in target exotic environments. • Approach 2 (pathways). The need of making invasion pathways secure by establishing sentinel nurseries of the most traded exotic plants to EU at their area of origin, and to monitor them for pathogens infection 3 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Sentinel trees network- Approach 1 Example 1: monitoring (how? Common protocols? WG2) the impact of native pathogens to European tree species planted in China Sentinel trees network- Approach 2 Example 2. monitoring (how? Common protocols? WG2) the presence of native organisms in Chinese tree species commonly exported to Europe, and potentially harmful to European plant communities 4 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Sentinel trees network Approach 1 Approach 2 Approach 1 1° 2° • symptoms and signs are expected (lack of co-evolution) • symptoms assessment, biological and molecular detection ARE NECESSARY • molecular analysis of resident microbial community is relevant • symptoms and sign are NOT necessarily expected (coevolution) • biological and molecular detection is relevant • Molecular analysis of resident microbial community IS NECESSARY European tree species planted in China • Plantation of European tree species in China (which propagation material? According to which agreement? WG1 &3) Q. suber • Survey of diseases (WG1&2 exp. design) Q. petraea 3° •Pathogens detection (how? Unique shared protocol? WG2) Q. ilex 5 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 1 01/04/2015 European tree species planted in China Fuyang-Zhejiang Approach 1 European tree species planted in China In 2008 bare-rooted plants were shipped to China (feasible as standard procedure? WG1 & 3) A phytosanitary certificate declared their healthy status (useful? WG3) The plants received a fungicide treatment: UNKNOWN The bare-rooted plants were kept 3 weeks in quarantine at the airport before being planted No symptoms were detectable after 3 weeks of quarantine 6 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 1 01/04/2015 Fungal detection Fungal isolation: morphological analysis Fungal isolation: molecular analysis (how to barcode? which markers? WG2) : Q. suber rDNA Internal Transcribed Spacer (ITS) glyceraldehyde-3-phosphate dehydrogenase (gpd) gene Q. petraea beta-tubulin gene Q.ilex Approach 1 454-NGS DNA extraction/amplification ITS1F-ITS2 (appropriate marker? WG2) Q. suber Pyrosequencing (other useful platforms? WG2) Reads: filtering and trimming Q. petraea Blastclust/Phylogenetic analysis (shared software & protocol WG2) Identification (which reference database? WG2) Q.ilex 7 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Symptoms assessment Approach 1 Signs and perythecia of Leptosphaeria cankers on Q. petraea Spots on Quercus spp. Conidia of Pestalopsis sp. and Alternaria sp. from Quercus spp. Signs of Erysiphe on Q. petraea Approach 1 A total of 9 OTUs have been identified of possible Asiatic origin 8 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 1 01/04/2015 OTU 102 refers to a Chinese Leptosphaeria sp The genus Leptosphaeria includes a large number of species mainly considered saprobic or necrothrophic on stems and leaves. Nevertheless the genus comprises also highly pathogenic species Approach 1 The OTUs 38 and 88 refer to the Mycosphaerella complex Mycosphaerella spp. are among the most common and destructive plant pathogens known, causing considerable economic losses on a wide variety of host plants worldwide, including economically important horticultural and ornamental crops 9 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 1 01/04/2015 OUT 4 refers to Erysiphe quercicola 2006- Takamatsu et al. proposed the Asian origin 2012 - E. quercicola has been detected in France and associated to flagshoot symptoms of Q. robur and Q. petraea 2008- Mougou et al. suggested that E. quercicola oak powdery mildew might originate from host shifts of tropical Erysiphe species introduced to Europe through infected exotic host plants 2014- Kirshner and Liu reported anamorphic E. quercicola on 2 tropical hosts commonly traded to Europe as ornamentals Approach 1 Discussion Our study reports for the first time the colonization of a selected collection of EU trees by native fungi while growing in China, and the potential of sentinel plantations to detect taxa pathogenic to EU trees that might pose a biosecurity risk for Europe. The sentinel plantation of Fuyang represents an improvement of the ISPN hypothesis based on the use of existing botanical gardens worldwide. Infact, in this study, the EU trees were selected according to ecological criteria (WG1). They were planted in China in sites comparable in climate and plant community composition to those of their area of origin in Europe (WG1). Presence of native species belonging to the same family or genus (e.g. the Fagaceae family in the Fuyang plot) and having similar ecological requirements enhances the probability of exposure of sentinel trees to natural inoculum pressure. The placing of the European trees in these specific sites was thought to favours “host jump” by native pathogens facilitating the evaluation of their aggressiveness. 10 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 1 01/04/2015 Discussion A total of 9 OTUs have been identified of possible Asiatic origin, based on clustering in NJ trees (WG2) within groups of sequences of taxa mostly reported from Asia. Four out of the nine taxa of Asiatic origin, are related to plant pathogenic genera and were associated with symptoms and signs typical of infection on the sentinel trees (WG2 prerequisite?). In conclusion, the sentinel plantations represent an appropriate answer to the growing need of preventive identification and characterization of plant pathogens at risk of introduction and invasion in Europe (and elsewhere). However the preliminary experience carried out in the Fuyang plantation highlighted the logistic and technical difficulties in utilizing sentinel trees for pathogens detection. Efforts should be made to solve regulatory and logistic bottlenecks associated with biosecurity issues (WG3) and the possibility of full characterization of biological samples, in order to make possible the routinary and reciprocal utilization of this approach between countries (WG3). Approach 2 monitoring the presence of native microbes in Chinese tree species commonly exported to Europe 11 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 2 01/04/2015 Why Approach 2 is important? Darwinian evolution predicts that, being adapted to and co-evolved with their hosts, many of these “unknown to science” are unlikely to do noticeable damage in their native ecosystems, and so are less likely to be detected even when introduced in a new environment with their native hosts We do not expect necessarily symptoms on native hosts caused by native pathogens Approach 2 Location of the sentinel tree plot in China Beijing Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 12 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 2 01/04/2015 Chinese tree species commonly exported to Europe (WG1&3) 1° • Plantation of Chinese species in China (WG1-3) 2° • Survey of diseases (WG1 & 2 exp. design) 3° • Pathogens detection (WG2) Approach 2 Samplings and diagnostic activities Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 13 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 2 01/04/2015 Biological detection Acer palmatum Fungal isolation: morphological analysis (protocols?) Zelkova schneideriana Fungal solation: molecular analysis (WG2 issue; appropriate barcoding?): Buxus microphylla rRNA gene internal transcribed spacer (ITS) glyceraldehyde-3-phosphate dehydrogenase (gpd) gene Ilex conrnuta beta-tubulin gene Fraxinus chinensis Approach 2 Symptoms assessment Deep canker Sup canker Shoot blight Fraxinus chinensis Ilex cornuta Acer palmatum Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 14 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Tricothecium roseum Approach 2 Biological detection Botryosphaeria dothidea Alternaria alternata Colletotrichum gleosporioides Phomopsis sp. Pestalotiopsis sp. Phoma sp. Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla Approach 2 monitoring the presence of native microbes in Chinese tree species commonly exported to Europe, and potentially harmful to European plant communities Chinese plants developed symptoms associated to worldwide diffused plant pathogens and to some taxa apparently not described (unknowns to science?) These undescribed taxa belong to genera that host a large number of plant pathogens For none of them has been possible to recognize a “chinese origin” (invasives?) However their pathogenicity to European ‘relatives’ hosts has to be studied (risk of host jump?) Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 15 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 2 01/04/2015 454-NGS Acer palmatum DNA extraction/amplification Zelkova schneideriana ITS1F-ITS2 Pyrosequencing Buxus microphylla Reads: filtering and trimming Blastclust/ Phylogenetic analysis Ilex conrnuta Identification Fraxinus chinensis Approach 2 NGS statistics 35.839 reads after trimming Minimum 93, maximum 6.549 per sample A total of 148 Operational Taxonomic Units Botryosphaeriales Chaetothyriales Dothideales Eurotiales Helotiales Lichenostigmatales Myriangiales Pleosporales Taphrinales Agaricales Erythrobasidiales Leucosporidiales Sporidiobolales Capnodiales Xylariales Dothideomycetes Glomerellales Hypocreales Microascales nd Saccharomycetales Trichosphaeriales Corticiales Filobasidiales Polyporales Tremellales 25 fungal orders Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 16 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Symptoms Acer palmatus Plant Stock SB1 Buxus microphylla Sentinel Nursery Taxa sp . Tr ro ich se o um th ec iu Co m lle to tri ch um sp Bo . do t r th yo id sp ea h ae ria Ph om op si s sp . Ph om a sp . Pe st al ot io ps is sp . Source Al te rn ar ia Hosts Plant Stock Fraxinus chinensis Ilex cornuta Zelkova schneideriana Sentinel Nursery Plant Stock Plant Stock Sentinel Nursery 6 LN1 DC1 DC2 DC1 DC2 SB SC1 SC2 SC3 SC4 SC5 LN1 LN2 LN1 SN1 SN2 SN3 1 1 9 8 3 21 10 2 6 1 2 1 2 7 2 4 2 2 3 3 2 2 1 1 1 4 2 9 3 4 2 SN4 3 Taphrina sp. 17 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Buxus microphylla Elsinoe sp. Max 89% identity on NCBI…possible new species Buxus microphylla Volutella buxi Pathogen on Buxus 18 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Buxus microphylla Colletotrichum yunnanense Endophyte on Buxus in China Liu, Xiaoying, Xiangming Xie & Junxing Duan. Colletotrichum yunnanense sp. nov., a new endophytic species from Buxus sp. Mycotaxon 100: 137–144. 2007. Buxus microphylla Phyllosticta citrichinaensis Foliar pathogen of Citrus in China 19 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Fraxinus chinensis Phyllactinia populi Powdery mildew of poplar in China and Korea (CABI) Blumeria graminis Powdery mildew of wheat: Japanese and Chinese genotypes? 20 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 01/04/2015 Fraxinus chinensis Strelitziana mali Zhang, Rong, Hanli Yang, Guangyu Sun, Huanyu Li, Jieli Zhuang, Xiaoru Zhai & Mark L. Gleason. Strelitziana mali, a new species causing sooty blotch on apple fruit. Mycotaxon 110: 477–485. 2009. Zhang, Rong, Hanli Yang, Guangyu Sun, Huanyu Li, Jieli Zhuang, Xiaoru Zhai & Mark L. Gleason. Strelitziana mali, a new species causing sooty blotch on apple fruit. Mycotaxon 110: 477–485. 2009. Approach 2 monitoring the presence of native microbes in Chinese tree species commonly exported to Europe, and potentially harmful to European plant communities NGS analysis revealed a rich fungal community associated to the 5 Chinese trees species Among them many common endophytes and epiphytes taxa A number of ‘known’ native fungal pathogens and additional ‘candidates’ have been identified whose impact to European plant community deserve to be investigated Some of these taxa were known as pathogens on plant hosts other than the 5 tree species considered in this study (possibility of unnoticed introduction) Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla 21 COST Action FP1401 Global Warning Trabzon Turkey 24-25/3/15 Approach 2 01/04/2015 monitoring the presence of native microbes in Chinese tree species commonly exported to Europe, and potentially harmful to European plant communities NGS seems to be a convenient technique to be used to scan the microbial community associated to native plants to be shipped overseas (yes it is but needs to be used in a shared protocol WG2) Obviously NGS results need confirmation through biological detection especially for those organisms potentially candidates to be aggressive to exotic hosts (very important but not necessarily feasible WG2) Furthermore the technique offers the opportunity to individuate undescribed taxa (unknown to science) Acer palmatum, Fraxinus chinensis , Ilex conrnuta , Zelkova schneideriana , Buxus microphylla Kauri trees threatened by Phytophthora taxon Agathis in New Zealand 22