Phytopathologia Mediterranea (2017) DOI: 10.14601/Phytopathol_Mediterr-21865 ABSTRACTS Abstracts of oral and poster presentations given at the 10th International Workshop on Grapevine Trunk Diseases, Reims, France, 4–7 July 2017 The 10th International Workshop on Grapevine Trunk diseases was held in Reims, France, on July 4–7 2017. This workshop was co-organized with the COST Action FA1303 entitled “Sustainable control of grape- vine trunk diseases” and supported by the International Organization of Vine and Wine (OIV). The meeting was attended by 240 participants from 29 countries and 155 papers were presented either as oral (63) or poster (92) presentations in four sessions: Pathogen characterization, Detection and epidemiology, Micro- bial ecology, Host-pathogen and fungus-fungus competitive interactions and Disease management. A field tour in the champagne vineyard was co-organized by the Comité Interprofessionnel du Vin de Champagne (CIVC). Delegates were presented with an overview of the Champagne region focussing on “terroir”, varietal crea- tion and grapevine diseases, especially GTDs. The tour concluded with a visit to Mercier cellar with cham- pagne tasting. The workshop is the 10th organized by the International Council on Grapevine Trunk Diseases (www. icgtd.org) and the 2nd one organised by the members of the COST Action FA1303 (www.managtd.eu). The next 11th IWGTD will be held in British Colombia Canada in 2019. Pathogen identification and worldwide, especially with grapevine trunk dis- characterization eases such as Petri disease and esca. Over the last 20 years, 29 species of this genus have been isolated Characterization and pathogenicity of Phaeo- from affected grapevines. However, the role of some acremonium species associated with Petri disease species as causal agents of grapevine dieback as well 1 and esca of grapevine in Spain. C. BERLANAS , J. as canker-causing agents is stills unknown. In this 2 1 3 PECENKA , B. LÓPEZ-M. , J. ARMENGOL and D. study, we surveyed vineyards of Vitis vinifera ‘Tem- 1. 1 GRAMAJE Instituto de Ciencias de la Vid y del Vino pranillo’ in La Rioja and Navarra regions in Spain (ICVV), Consejo Superior de Investigaciones Científicas, (2015–2016). Wood samples from grapevines show- Universidad de la Rioja, Gobierno de La Rioja, Ctra. LO- ing general decline, dieback and “tiger-stripe” foliar 2 20 Salida 13, 26071 Logroño, Spain. Mendel University symptoms yielded 40 fungal isolates identified as in Brno, Faculty of Horticulture, Mendeleum - Institute Phaeoacremonium spp. These isolates were character- of Genetics CZ-69144 Lednice, Valtická 334, Czech Re- ized based on the effect of temperature on mycelial 3 public. Instituto Agroforestal Mediterráneo, Universitat growth, comparisons of DNA sequence data of β- tu- Politècnica de València, Camino de Vera s/n, 46022 Va- bulin and actin and on the basis of their MSP-PCR lencia, Spain. E-mail: [email protected] profiles. Additionally, 32 isolates belonging to ten Phaeoacremonium species collected from 2003 to 2015 Phaeoacremonium species have been associated with in different regions of Spain were retrieved from the disease symptoms of a number of woody hosts www.fupress.com/pm ISSN (print): 0031-9465 Firenze University Press ISSN (online): 1593-2095 © 2017 Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC-BY-4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 10th International Workshop on Grapevine Trunk Diseases, Reims, France, 4–7 July 2017 culture collection of the IAM-UPV (Spain) and in- on the agar and the good performance obtained in cluded in this study. Phenotypic and molecular stud- the recovery of D. torresensis from both sterile and ies identified fivePhaeoacremonium species associated non-sterile soil samples. Secondly, we assessed the with grapevine decline: P. fraxynopennsylvanicum, P. usefulness of the GFBRBA medium for estimating krajdenii, P. minimum, P. parasiticum and P. sicilianum. black-foot disease pathogens populations in eight P. minimum was the most frequently isolated species naturally infested soils (nursery field, nursery field (65% of the isolates) followed by P. sicilianum (25%). in rotation, young and mature vineyards). All fields A total of 11 isolates representing all Phaeoacremoni- were positive for the presence of black-foot patho- um species were used in three different pathogenici- gens. D. torresensis was the most frequently isolated ty studies. All species caused black discolouration in species from all soils tested. In general, established the xylem vessels of green shoots and potted grape- vineyards and nursery fields had higher inoculum vine rootstock five months after inoculations, being density of D. torresensis than nursery fields in rota- P. fraxynopennsylvanicum and P. minimum the most tion. Other black-foot species isolated from soil were virulent species. Seedlings rated 2 months after in- D. alcacerensis (young vineyard and field nursery) oculation showed that Phaeoacremonium spp. caused and Ilyonectria liriodendri (field nursery). We also ex- low vascular discoloration and symptom expression. amined how shifts in the abundance and composi- P. fraxynopennsylvanicum and P. scolyti were the most tion of black-foot pathogens correspond to changes virulent species, with 31.25% of the inoculated plants in specific soil properties. Our results showed a posi- showing symptoms of chlorotic leaves, severe defo- tive relationship between calcium carbonate and the liation and wilting. CFUs level of black-foot pathogens in soil. Further research is needed to elucidate the interactions of primary and secondary macronutrients, micronutri- An improved medium for estimating black-foot ents and other physicochemical properties, with dis- disease pathogens populations in naturally infest- ease in enhancing or minimizing black-foot disease ed soils and their relation to production systems incidence in grapevine. and soil properties. C. BERLANAS, B. LÓPEZ- MANZANARES and D. GRAMAJE. Instituto de Ciencias de la Vid y del Vino (ICVV), Consejo Superior de Are stone fruit trees alternative hosts of grapevine Investigaciones Científicas, Universidad de la Rioja, Gob- trunk diseases in Germany? S. BIEN, U. BRAUN2 ierno de La Rioja, Ctra. LO-20 Salida 13, 26071 Logroño, and U. DAMM1. Senckenberg Museum of Natural His- Spain E-mail: [email protected] tory Görlitz, PF 300 154, 02806 Görlitz, Germany. 2Lu- ther-Universität Halle-Wittenberg, Neuwerk 21, 06108 Early, specific, and accurate detection of black-foot Halle (Saale), Germany. E-mail: steffen.bien@sencken- pathogens in soil is essential to prevent the infection berg.de of grapevine planting material by these pathogens in field nurseries and also during the first years after Germany belongs to the important producers of planting. In this study, we comparatively assessed sweet cherry, sour cherry and plum (Prunus spp.) the accuracy and efficiency of three modified culture worldwide. Surveys on fungi associated with wood media protocols published in the literature for the necroses, dieback and decline symptoms of stone detection of viable inoculum of soilborne pathogens fruit trees and grapevine in South Africa report simi- phylogenetically related to black-foot genera based lar pathogen communities. As part of the German on plating dry soil samples: a modification of Rose Barcoding of Life project, the fungal diversity asso- Bengal Agar (MRBA), Glucose-Faba Bean Rose Ben- ciated with wood necroses of commercially grown gal Agar (GFBRBA) and Glucose-Faba Bean Agar Prunus trees from the most important fruit producer (GFBA). Firstly, we compared their efficiency for regions in Germany was investigated. First results growing selected black-foot pathogens and the re- that are based on morphological and ITS sequence covery of Dactylonectria torresensis from sterile and data of more than 600 isolates comprise at least 60 non-sterile soil. GFBRBA was selected for further genera of Ascomycota, 12 genera of Basidiomycota studies based on the ability of most of the black- and two genera of Zygomycota. The dominating foot species to produce a brown or yellow pigment ascomycete genera include Aposphaeria, Collophora Phytopathologia Mediterranea 10th International Workshop on Grapevine Trunk Diseases, Reims, France, 4–7 July 2017 and Calosphaeria. So far, our study revealed several DNA of their corresponding target Diatrypaceae and grapevine trunk disease pathogens on stone fruit Botryosphaeriaceae species (nine each) while none trees in Germany, for example Cytospora spp., Dia- of the 20 non-target species were amplified. The two porthe spp., Eutypa lata and Phaeoacremonium spp., qPCR methods were suitable for amplifying puri- while Phaeomoniellaceae is lacking. Based on results fied DNA, synthetic DNA fragments (gBlocks®) and from South Africa, a wider occurrence of members mixed DNA from spore trap tapes. The Diatrypaceae of Botryosphaeriaceae was expected, however only primers that amplify a fragment of the rRNA gene Diplodia seriata has been found. had a limit of detection (LOD) of ~20 fg of purified DNA which is equivalent to less than one spore. The LOD for Botryosphaeriaceae primers, that amplify a Development of molecular tools for the detection fragment of the β-tubulin gene, was ~300 fg of puri- and quantification of Eutypa and Botryosphaeria fied DNA which is equivalent to seven spores. The dieback