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Session 1 – Evolution and Natural Variation S1.2- Evolution and taxonomic split of the model grass Brachypodium distachyon (L.) P. Beauv. Pilar Catalán 1, Jochen Müller 2, Robert Hasterok 3, Glyn Jenkins 4, Luis A. J. Mur 4, Tim Langdon 4, Alexander Betekhtin 3, Dorota Siwinska 3, Manuel Pimentel 5, Diana López- Alvarez 1 1 Department of Agriculture (Botany), High Polytechnic School of Huesca, University of Zaragoza, Ctra. Cuarte km 1, 22071 Huesca, Spain 2 Herbarium Haussknecht, Department of Systematic Botany, University of Jena, Fürstengraben 1, 07737 Jena, Germany 3 Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia, Jagiellonska 28, 40032 Katowice, Poland 4 Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Plas Gogerddan, Aberystwyth SY23 3EB Wales, UK 5 Department of Plant and Animal Biology and Ecology, Faculty of Biology, University of Coruña, Campus da Zapateira s. n., 15071 A Coruña, Spain pcatalan@unizar.es Abstract A multidisciplinary phenetic, cytogenetic and evolutionary study has been conducted on a representative sampling of the three known cytotypes of the model grass Brachypodium distachyon (2n = 10, 20, 30). Statistical analyses of 15 selected traits in greenhouse propagated individuals detected significant taxonomic differences between the three cytotypes that have been further validated through discriminant analysis of wild individuals, demonstrating stability of characters in natural populations. Cytogenetic analyses based on nuclear genome size estimation, fluorescence in situ hybridisation with genomic and multiple DNA sequences as probes and chromosome painting confirm that the 2n=10 and 2n=20 chromosome cytotypes correspond to two different diploid taxa, whereas the 2n=30 cytotype is a derived allotetraploid of the cross between them. Phylogenetic analysis based on two plastid (ndhF, trnLF) and five nuclear (ITS, ETS, CAL, DGAT, GI) genes have demonstrated that the 2n=20 and 2n=10 cytotypes were, respectively, the maternal and paternal genome donors of the 2n=30 cytotype. The substantial phenotypic, cytogenetic and molecular differences detected among the three B. distachyon s. l. cytotypes are indicative of major speciation processes within this complex that allow their taxonomic separation into three distinct species. We have kept the name B. distachyon for the 2n=10 cytotype, whose genome has been fully sequenced and which is being used as model grass for temperate cereals, and have consequently designated a new epitype for it; we have described two new species B. stacei and B. hybridum for, respectively, the 2n=20 and 2n=30 cytotypes. The completely sequenced B. distachyon genome and the future availability of fully sequenced B. stacei and B. hybridum genomes would provide an exceptional opportunity for thorough comparative phylogenomic analyses of these plants and other totally or partially sequenced grasses. References Catalán P, Müller J, Hasterok R, et al. (2011) Next generation systematics: evolution and taxonomic split of the model grass Brachypodium distachyon (L.) P. Beauv. (Poaceae). submitted. Hasterok R, Draper J, Jenkins G (2004) Laying the cytotaxonomic foundations of a new model grass, Brachypodium distachyon (L.) Beauv. Chromosome Research 12:397-403. Idziak D, Betekhtin A, Wolny E, et al. (2011) Painting the chromosomes of Brachypodium-current status and future prospects. Chromosoma: Epub ahead of print, doi 10.1007/s00412-00011-00326-00419 Mur L-A, Allainguillaume J, Catalan P, et al. (2011) Exploiting the Brachypodium Tool Box in cereal and grass research. New Phytologist 191: 334-347. Wolny E, Lesniewska K, Hasterok R, Langdon T (2011) Compact genomes and complex evolution in the genus Brachypodium. Chromosoma 120:199-212 Keywords Brachypodium distachyon, Brachypodium stacei, Brachypodium hybridum, cytogenetics, evolutionary systematics 11
Session 1 – Evolution and Natural Variation S1.3- Using Brachypodium distachyon for model to crop translation of disease resistance in cereals. Antoine Peraldi, Andrew Steed, Chris Burt, Paul Nicholson. Department of Disease and Stress and Stress Biology, John Innes Centre, Colney Lane, Norwich, NR4 7UH, UK. antoine.peraldi@bbsrc.ac.uk Abstract Cereal production needs to improve in both quality and yield during the twenty first century to cope with predicted global challenges such as climate change, rising biofuel demand and human demographic pressure. Cereal diseases such as Fusarium head blight (FHB) of wheat can reduce yield and also contaminate grain with mycotoxins harmful for both animal and human consumption. Despite numerous studies on the genetic components of resistance to Fusarium diseases, progress is impaired by the complexity of the wheat genome and lack of available genome sequence. Therefore research would benefit greatly from availability of a robust, tractable genetic model from which to undertake model to crop translation. Brachypodium distachyon (Bd) has numerous advantages both as a genetic model and in functional genetic studies because of the increasing availability of appropriate tools (Draper et al., 2001). We have demonstrated that Bd exhibits compatible interactions with the main FHB-causing species of Fusarium and mirrors the disease symptom development on wheat better that any other model proposed to date (Peraldi et al., 2011). This new pathosystem enables screening of Bd mutant populations (i.e.T-DNA, Vain et al., 2008) to identify genes involved in resistance to Fusarium. Once characterized, these gene candidates can be validated in the natural host using reverse genetics approaches (e.g TILLING). Using this approach, a Bd mutant was identified that conferred increased resistance to Fusarium infection in detached leaf and flower inoculation tests. Sequence alignments and dark-induced senescence tests were used to characterize this gene as a functional homologue of auxin response factor (ARF) 2. The potential role of ARF2 in the natural host was evaluated using virus-induced gene silencing (VIGS) of wheat ARF2 which resulted in an average reduction in FHB disease severity of 20%. References: Draper J, Mur LAJ, Jenkins G, et al. (2001) Brachypodium distachyon. A new model system for functional genomics in grasses. Plant Physiology 127:1539-1555. Peraldi A, Beccari G, Steed A, Nicholson P. (2011) Brachypodium distachyon: a new pathosystem to study Fusarium head blight and other Fusarium diseases of wheat. BMC Plant Biology 11:100. Vain P, Worland B, Thole V, et al. (2008) agrobacterium-mediated transformation of the temperate grass Brachypodium distachyon (genotype Bd21) for T-DNA insertional mutagenesis. Plant Biotechnology Journal 6:236-245. Keywords Brachypodium, Fusarium, wheat, pathogen resistance, model to crop translation. 12
Page 2 and 3: Acknowledgements: Institut National
Page 4 and 5: Contents Programme 4 Oral presentat
Page 6 and 7: Wednesday 19 th October, 2011 11:00
Page 8 and 9: Friday 21 st October, 2011 Biotic a
Page 10 and 11: ORAL COMMUNICATIONS 9
Page 14 and 15: Session 1 - Evolution and Natural V
Page 18 and 19: Session 2 - Cell Wall, Biomass and
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Page 32 and 33: Session 4 - Biotic and Abiotic Stre
Page 42 and 43: Session 5 - Plant Development, Meta
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Session 3 - Tools and Bioengineerin
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Session 3 - Tools and Bioengineerin
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Session 4 - Biotic and Abiotic Stre
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Session 4 - Biotic and Abiotic Stre
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Session 5 - Plant Development, Meta
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Session 5 - Plant Development, Meta
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S: Speakers’ abstracts P: Posters
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LIST OF PARTICIPANTS 75
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BOUCHABKE-COUSSA Oumaya INRA IJPB I
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GIRALDO Patricia E.T.S.I. Agronomos
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MARION-POLL Annie INRA IJPB Institu
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RENAULT Hugues CNRS - IBMP Institut
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WARD Eric Two Blades Foundation, P.
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