Gulrust i korn og frøgræs. Hvilke arter og sorter er mest udsatte?

Transkript

1 Gulrust i korn og frøgræs. Hvilke arter og sorter er mest udsatte? Mogens S. Hovmøller Annemarie F. Justesen

2 Tre hovedkategorier af rust på korn og græs Gulrust Brunrust/ kronrust Sortrust

3 International bekymring om hvederust

4 International bekymring om hvederust

5 Borlaug Global Rust Initiative

6 Global Rust Reference Center (GRRC) Aarhus University - Flakkebjerg Detected 2000 Detected 2000 Detected 2002 GRC-YR forms an umbrella of research and surveillance for improving wheat yellow rust (WYR) management in developing countries where facilities and expertise are scarce. The three wheat rusts, stem or black rust (Puccinia graminis tritici), leaf or brown rust (P. triticina), and stripe or yellow rust (P. striiformis tritici) prevail in most areas where wheat is grown. WYR remains the major rust causing yield losses in most wheatgrowing areas. It has recently become a major problem in North America, Australia and across large areas in Africa and Asia due to the emergence and spread of an aggressive strain adapted to warmer temperatures WYR epidemic in progress (photo: EA Milus) /2 1990/1 1992/3 1995/6 1997/8 Yr9-virulent WYR movements Historical records show that races occurring in Europe reached North America (1915) and Australia (1979). Yr9 virulent races were spread in Africa and Asia in the 1980s, and races occurring in West Asia reached South Africa (2000) and Northern Europe (2000). The recent spread of an aggressive race into North America (2000) and Australia (2002) highlights the global movement potential of the pathogen, presumably by high altitude winds or as contaminants via human travel or transport. Examples of reported yield losses in different wheat growing areas Country Period Yield Loss (%/ Metric tons in period considered) Estimated cost* ($ million USD) Azerbaijan > 30% each year 78 Tajikistan % loss 28 Turkey Million tons Million tons 120 Uzbekistan % loss 136 Morocco % yield loss in Seis region 30 USA Million Metric tons 750 Australia Chemical control costs 195 * Based on Wheat world price during reported period The emergence of aggressive yellow rust strains adapted to warmer temperatures calls for immediate coordinated multi-national action to delay and alleviate the consequences of global spread: Hence, the establishment of GRC-YR as a component of the Borlaug Global Rust Initiative ( Principal objectives of GRC-YR Undertaking pathogen assays: Virulence and race analyses, diversity studies on aggressiveness, DNA fingerprinting Securing unique pathogen resources for future resistance breeding and research Providing basic information for a global WYR early warning system Facilitating research and training in WYR epidemiology, population genetics and evolution During the last two decades, numerous yellow rust epidemics have caused10-60% losses in wheat production. Grain losses in wheat following the introduction and spread of an aggressive yellow rust race adapted to warmer temperatures (virulent for the Yr6, Yr7, Yr8 and Yr9 resistance genes) amounted to a loss of 18 million tonnes in the USA over a three year period. With the increased frequency of inter-continental spread of the yellow rust fungus, it is only a matter of time until virulent races overcoming currently deployed resistance genes such as Yr18 and Yr27 are distributed worldwide. The speed of pathogen reproduction is a key factor in epidemics and depends on the prevalent environmental conditions and the wheat varieties planted. Expected outputs: Phylo-geographic relationships in WYR reconstructed on a global scale Global and regional WYR dispersal pathways tracked Changes in effectiveness of WYR resistance genes in major wheat varieties assessed Conservation of global WYR cultures secured Key WYR resources provided to wheat breeding programs Junior scientists and graduate students trained in WYR Web-based reporting tools for pathogen and disease data management established A global early warning system for WYR established Aarhus University (AU) - Faculty of Agricultural Sciences, Denmark International Center for Agricultural Research in the Dry Area (ICARDA) International Maize and Wheat Improvement Center (CIMMYT) Revised May 12, 2009

7 Hvorfor gulrust? 1. Aggressiv gulrust mere hyppige og kraftige epidemier også i verdens varme og tørre områder øget usikkerhed om fødevareforsyning, specielt i 3. verdenslande 2. Øget diversitet af gulrust angreb på både korn og frøgræs flere smitte-racer nogle racer går på tværs af kornarterne Foto: Lise N Jørgensen

8 Tre typer gulrust i Danmark 1. Korn: Byg Hvede Triticale - Rug 2. Engrapgræs 3. Hundegræs Værtspecifik

9 Tre typer gulrust i Danmark Krydssmitte:

10 Gulrust frøgræs Efterårsangreb er blevet hyppigere kan være kraftige, specielt i engrapgræs Betydning af gulrust dårligt belyst (en del erfaringer men få forsøg) Store forskelle i modtagelighed mellem sorter og arter (ikke systematisk undersøgt) Kortlægning af forekomst af sygdomme i frøgræs påbegyndt i 2010 (frøavlskonsulenter og AU)

11 Sygdomme i frøgræs i praksis 2010 Foto: Ghita Nielsen

12 Gulrust i korn Triticale og hvede mest udsat Store arts- og sortsforskelle (x smitte-racer) Triticale Tidligere betragtet som robust afgrøde modtagelig i det tidlige forår mindre modtagelig som voksen plante Siden 2007: Flere sorter ekstremt modtagelig andre resistente (aggressiv gulrust)

13 Dinaro Tulsa race Alsted Svedale (Skåne) 30. juni 2010 Dinaro Triticale race (aggressiv) Alsted Svedale (Skåne) 30. juni 2010 Photo MSH

14 2009 resultater Kerneudbytte hkg/ha Ubehandlet Behandlet % gulrust Sort 1 gent 4 gent. 3. juni Valentino Dinaro SW Talentro Korpus Cando TI Gringo EAW G144a Pigmej Tarzan Ragtac Gns. Stærkt modtagelig (5 sorter: >=50% angreb) 10.1 hkg/ha Gns. Resistente sorter (6 sorter: <=0.5% angreb) 84.1 hkg/ha Kilde: Nordic Seed (Erik Tybirk, 2010)

15 Tabel 2 (uddrag): Gulrust og hvedesorter

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17 Hvilke arter og sorter er mest udsatte? Korn: 1. Triticale 2. Vinterhvede 3. Vårhvede 4. Rug 5. Byg Græsser: 1. Engrapgræs 2. Hundegræs 3. Vilde græsser? Konkret risiko afhænger af smitte-race, aggressivitet og sorternes resistens! Undgå at dyrke meget modtagelige sorter

18 Hvilke arter og sorter er mest udsatte? Oplysninger om sortsmodtagelighed 1. SortInfo 2. Sortsforsøg: Korn, bælgsæd,olieplanter 3. DLBR Landbrugsinfo 4. Nyt projekt (2011): Resistens mod gulrust i Triticale og vårhvede. Fonden for Økologisk Landbrug Oplysninger om smitteracer (DK & Europa) 1. EUROWheat