IOBC / WPRS Working group „Integrated Protection of Fruit Crops” Sub group “Pome Fruit Diseases” Proceedings of the Meetings at Lindau (Germany) 31 August – 5 September 2002 and Piacenza (Italy) 31 August – 3 September 2005 Edited by Cesare Gessler, Vittorio Rossi and Simona Giosuè IOBC wprs Bulletin Bulletin OILB srop Vol. 29 (1) 2006 The content of the contributions is in the responsibility of the authors The IOBC/WPRS Bulletin is published by the International Organization for Biological and Integrated Control of Noxious Animals and Plants, West Palearctic Regional Section (IOBC/WPRS) Le Bulletin OILB/SROP est publié par l‘Organisation Internationale de Lutte Biologique et Intégrée contre les Animaux et les Plantes Nuisibles, section Regionale Ouest Paléarctique (OILB/SROP) Copyright: IOBC/WPRS 2006 The Publication Commission of the IOBC/WPRS: Horst Bathon Luc Tirry Federal Biological Research Center University of Gent for Agriculture and Forestry (BBA) Laboratory of Agrozoology Institute for Biological Control Department of Crop Protection Heinrichstr. 243 Coupure Links 653 D-64287 Darmstadt (Germany) B-9000 Gent (Belgium) Tel +49 6151 407-225, Fax +49 6151 407-290 Tel +32-9-2646152, Fax +32-9-2646239 e-mail: [email protected] e-mail: [email protected] Address General Secretariat: Dr. Philippe C. Nicot INRA – Unité de Pathologie Végétale Domaine St Maurice - B.P. 94 F-84143 Monfavet Cedex France ISBN 92-9067-184-8 http://www.iobc-wprs.org Pome Fruit Diseases IOBC/wprs Bull. 29(1), 2006 Preface This Bulletin contains the proceedings of the meetings of the IOBC/WPRS Working Group “Integrated Protection of Fruit Crops” subgroup “Pome fruits diseases”. This volume includes the contributions from two workshops: the 6th International Workshop on Pome fruit Diseases held in Lindau, Germany, 31 August – 5 September 2002, and the 7th International Workshop on Orchard Diseases, held in Piacenza, Italy, 31 August – 3 September 2005. The Bulletin contains 41 contributions: 16 from the Lindau meeting and 25 from Piacenza. They concern several aspects of the most important fruit crop diseases, including epidemiology, biological and integrated control. Also diseases of increasing importance in Europe, like brown spot and bark canker on pears, were deeply investigated by several contributions of participants and round tables. In aggregate, 78 scientists from 15 countries in Europe, United States and Canada attended the Workshops. The local organization of the Workshops was handled by Peter Triloff and myself in collaboration with competent co-workers, for Lindau and Piacenza, respectively. Both organizers took care of the scientific planning and also handled the organizing details to guarantee successful meetings. In both occasions excursions were planned to visit pear and apple orchards both conventional and organic, showing different cropping methods, pathological problems, and strategies of fungicide applications. The next Workshop of this subgroup will be organized in Denmark in 2008, probably in October, by Arne Stensvand and two colleagues from Denmark. I believe that this Bulletin will be an useful tool for scientists and technicians as an updating of the knowledge about epidemiology and optimal control strategies for both well known and emerging diseases. Vittorio Rossi Convenor of the subgroup “Pome fruit diseases” i ii We thank all the sponsors of the meeting in Lindau (2002): iii Contents Preface........................................................................................................................................ i Sponsors of the Lindau Meeting .............................................................................................. ii List of Participants in Lindau, 2002........................................................................................ vii List of Participents in Piacenza, 2005 ...................................................................................... xi Meeting at Lindau (Germany), 2002 Control of apple scab (Venturia inaequalis) in organic apple growing. StopScab: A Danish research programme for screening substitutes to copper fungicides Marianne Bengtsson, John Hockenhull ........................................................................... 1 Apple scab IPM: preliminary report on the application of a new sampling technique to determine “scab-risk” J. Reardon, L. Berkett, M. Garcia, A. Gotlieb, T. Ashikaga, G. Badger.......................... 5 Spatial distribution of ascospores of Venturia inaequalis within the tree canopy O. Carisse, D. Rolland, J. Charest................................................................................... 9 Sanitation practices to reduce apple scab inoculum in orchards Piet Creemers, Alida Vanmechelen, Kjell Hauke .......................................................... 15 Effect of apple cultivar mixtures on the epidemic of Venturia inaequalis in a treated orchard F. Didelot, L. Brun, S. Clément, L. Parisi...................................................................... 25 Phytotoxic effect of lime sulphur on apple and pear Bart Heijne, Peter Frans de Jong, Imre Janos Holb ..................................................... 31 Pome fruit storage diseases Joana Henriques ............................................................................................................ 37 Durable disease resistance and high fruit quality, a challenge for apple breeding Markus Kellerhals, Cornelia Sauer, Ernst Höhn, Barbara Guggenbühl, Jürg Frey, Robert Liebhard, Cesare Gessler ......................................................................... 43 Geographical distribution of Venturia inaequalis strains virulent to the Vf gene in Europe L. Parisi, F. Laurens, F. Didelot, K. Evans, C. Fischer, V. Fouillet, F. Gennari, H. Kemp, M. Lateur, A. Patocchi, H. Schouten, C. Tsipouridis..................................... 49 Factors influencing deposition of Venturia inaequalis ascospores on apple trees Vittorio Rossi, Simona Giosuè, Riccardo Bugiani ........................................................ 53 A Chorus tolerant population of Venturia inaequalis found in a South African apple orchard Wolf Schwabe ................................................................................................................ 59 Evaluation of in-vitro grown apple shoot sensitivity to Venturia inaequalis using a detached leaf assay E. Silfverberg-Dilworth, Andrea Patocchi, Cesare Gessler .......................................... 67 An adaptation of the New Hampshire degree-day model to predict ascospore release of Venturia inaequalis in Norway Arne Stensvand, David M. Gadoury, Terje Amundsen, Robert C. Seem ....................... 75 iv Meteorological data for warning systems: some views concerning sensors Christer Tornéus ............................................................................................................ 83 The simulation of ascospore release from apple scab: do we use suitable climatic data? Peter Triloff.................................................................................................................... 87 Chemical control of apple powdery mildew (Podosphaera leucotricha): mode of actions Xiangming Xu, Joyce Robinson, Angela Berrie ............................................................. 95 Meeting at Piacenza (Italy), 2005 Biological characteristics of dicarboximide-resistant isolates of Stemphylium vesica- rium from Italian pear orchards Giulia Alberoni, Marina Collina, Agostino Brunelli .................................................. 109 Control of brown spot of pear in organic pear orchard Loredana Antoniacci, Riccardo Bugiani, Rossana Rossi ........................................... 117 Screening of organically based fungicides for apple scab (Venturia inaequalis) control and a histopathological study of the mode of action of a resistance inducer Marianne Bengtsson, Hans J. Lyngs Jørgensen, Anh Pham, Ednar Wulff, John Hockenhull ................................................................................................................... 123 Development of an integrated pest and disease management system for apples to produce fruit free from pesticide residues – Aspects of disease control Angela Berrie, Jerry Cross........................................................................................... 129 Evaluation of alternative treatments to urea to eliminate leaf litter in organic apple production Angela Berrie, Barbara Ellerker, Karen Lower .......................................................... 139 Heterogeneity in apple scab: implication for management Odile Carisse, C. Meloche, Tristan Jobin, D. Rolland ................................................ 145 Field and in vitro sensitivity of Valsa ceratosperma (Cytospora vitis) to fungicides Marina Collina, Elena Cicognani, Benedetta Galletti, Agostino Brunelli .................. 151 Sensitivity in vitro of Stemphylium vesicarium to fungicides Marina Collina, Giulia Alberoni, Agostino Brunelli .................................................. 155 Relationship between biological agent populations and biocontrol of Monilinia spp in peaches Antonieta De Cal, Inmaculada Larena, Belén Guijarro, Rosario Torres, Mar Liñan, Pietro Domenichini, Alberto Bellini, Xavier Ochoa de Eribe, Josep Usall, Paloma Melgarejo ....................................................................................................... 163 Modelling dynamics of airborne conidia of Stemphylium vesicarium, the causal agent of brown spot