Mapping spot blotch resistance genes in four barley populations

Bipolaris sorokiniana (teleomorph: Cochliobolus sativus) is the fungal pathogen responsible for spot blotch in barley (Hordeum vulgare L.) and occurs worldwide in warmer, humid growing conditions. Current Australian barley varieties are largely susceptible to this disease and attempts are being made to introduce sources of resistance from North America. In this study we have compared chromosomal locations of spot blotch resistance reactions in four North American two-rowed barley lines; the North Dakota lines ND11231-12 and ND11231-11 and the Canadian lines TR251 and WPG8412-9-2-1. Diversity Arrays Technology (DArT)-based PCR, expressed sequence tag (EST) and SSR markers have been mapped across four populations derived from crosses between susceptible parental lines and these four resistant parents to determine the location of resistance loci. Quantitative trait loci (QTL) conferring resistance to spot blotch in adult plants (APR) were detected on chromosomes 3HS and 7HS. In contrast, seedling resistance (SLR) was controlled solely by a locus on chromosome 7HS. The phenotypic variance explained by the APR QTL on 3HS was between 16 and 25% and the phenotypic variance explained by the 7HS APR QTL was between 8 and 42% across the four populations. The SLR QTL on 7HS explained between 52 to 64% of the phenotypic variance. An examination of the pedigrees of these resistance sources supports the common identity of resistance in these lines and indicates that only a limited number of major resistance loci are available in current two-rowed germplasm

Crop Updates 2001 - Cereals

This session covers forty two papers from different authors: PLENARY 1. Planning your cropping program in season 2001, Dr Ross Kingwell, Agriculture Western Australia and University of Western Australia WORKSHOP 2. Can we produce high yields without high inputs? Wal Anderson, Centre for Cropping Systems, Agriculture Western Australia VARIETIES 3. Local and interstate wheat variety performance and $ return to WA growers, Eddy Pol, Peter Burgess and Ashley Bacon, Agritech Crop Research CROP ESTABLISHMENT 4 Soil management of waterlogged soils, D.M. Bakker, G.J. Hamilton, D. Houlbrooke and C. Spann, Agriculture Western Australia 5. Effect of soil amelioration on wheat yield in a very dry season, M.A Hamza and W.K. Anderson, Agriculture Western Australia 6. Fuzzy tramlines for more yield and less weed, Paul Blackwell1 and Maurice Black2 1Agriculture Western Australia, 2Harbour Lights Estate, Geraldton 7. Tramline farming for dollar benefits, Paul Blackwell, Agriculture Western Australia NUTRITION 8. Soil immobile nutrients for no-till crops, M.D.A. Bolland1, R.F. Brennan1,and W.L. Crabtree2, 1Agriculture Western Australia, 2Western Australian No-Tillage Farmers Association 9. Burn stubble windrows: to diagnose soil fertility problems, Bill Bowden, Chris Gazey and Ross Brennan, Agriculture Western Australia 10. Calcium: magnesium ratios; are they important? Bill Bowden1, Rochelle Strahan2, Bob Gilkes2 and Zed Rengel2 1Agriculture Western Australia, 2Department of Soil Science and Plant Nutrition, UWA 11. Responses to late foliar applications of Flexi-N, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 12. A comparison of Flexi-N placements, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 13. What is the best way to apply potassium? Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, CSBP futurefarm 14. Claying affects potassium nutrition in barley, Stephen Loss, David Phelps, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm 15. Nitrogen and potassium improve oaten hay quality, Stephen Loss, Tim O’Dea, Patrick Gethin, Ryan Guthrie, Lisa Leaver, CSBP futurefarm AGRONOMY 16. Agronomic responses of new wheat varieties in the northern wheatbelt, Darshan Sharma and Wal Anderson, Agriculture Western Australia 17. Wheat agronomy research on the south coast, Mohammad Amjad and Wal Anderson, Agriculture Western Australia 18. Influence of sowing date on wheat yield and quality in the south coast environment, Mohammad Amjadand Wal Anderson, Agriculture Western Australia 19. More profit from durum, Md.Shahajahan Miyan and Wal Anderson, Agriculture Western Australia 20. Enhancing recommendations of flowering and yield in wheat, JamesFisher1, Senthold Asseng2, Bill Bowden1 and Michael Robertson3 ,1AgricultureWestern Australia, 2CSIRO Plant Industry, 3CSIRO Sustainable Ecosystems 21. When and where to grow oats, Glenn McDonald, Agriculture Western Australia 22. Managing Gaidner barley for quality, Kevin Young and Blakely Paynter, Agriculture Western Australia PESTS AND DISEASES 23. Strategies for leaf disease management in wheat, Jatinderpal Bhathal1, Cameron Weeks2, Kith Jayasena1 and Robert Loughman1 ,1Agriculture Western Australia. 2Mingenew-Irwin Group Inc 24. Strategies for leaf disease management in malting barley, K. Jayasena1, Q. Knight2 and R. Loughman1, 1Agriculture Western Australia, 2IAMA Agribusiness 25. Cereal disease diagnostics, Dominie Wright and Nichole Burges, Agriculture Western Australia 26. The big rust: Did you get your money back!! Peter Burgess, Agritech Crop Research 27. Jockey – winning the race against disease in wheat, Lisa-Jane Blacklow, Rob Hulme and Rob Giffith, Aventis CropScience 28. Distribution and incidence of aphids and barley yellow dwarf virus in over-summering grasses in WA wheatbelt, Jenny Hawkes and Roger Jones, CLIMA and Agriculture Western Australia 29. Further developments in forecasting aphid and virus risk in cereals, Debbie Thackray, Jenny Hawkes and Roger Jones, Agriculture Western Australia and Centre for Legumes in Mediterranean Agriculture 30. Effect of root lesion nematodes on wheat yields in Western Australia, S. B. Sharma, S. Kelly and R. Loughman, Crop Improvement Institute, Agriculture Western Australia 31. Rotational crops and varieties for management of root lesion nematodes in Western Australia, S.B. Sharma, S. Kelly and R. Loughman, Crop Improvement Institute, Agriculture Western Australia WEEDS 32. Phenoxy herbicide tolerance of wheat, Peter Newman and Dave Nicholson, Agriculture Western Australia 33. Tolerance of wheat to phenoxy herbicides,Harmohinder S. Dhammu, Terry Piper and Mario F. D\u27Antuono, Agriculture Western Australia 34. Herbicide tolerance of durum wheats, Harmohinder S. Dhammu, Terry Piper and David Nicholson, Agriculture Western Australia 35. Herbicide tolerance of new wheats, Harmohinder S. Dhammu, Terry Piper and David F. Nicholson, Agriculture Western Australia BREEDING 36. Towards molecular breeding of barley: construction of a molecular genetic map, Mehmet Cakir1, Nick Galwey1, David Poulsen2, Garry Ablett3, Reg Lance4, Rob Potter5 and Peter Langridge6,1Plant Sciences, Faculty of Agriculture, UWA, 2Queensland Department of Primary Industries, Qld, 3Centre for Plant Conservation Genetics Southern Cross University, Lismore NSW, 5SABC Murdoch University, WA, 6Department of Plant Science University of Adelaide, Glen Osmond SA 37. Toward molecular breeding of barley: Identifying markers linked to genes for quantitative traits, Mehmet Cakir1, Nick Galwey1, David Poulsen2, Reg Lance3, Garry Ablett4, Greg Platz2, Joe Panozzo5, Barbara Read6, David Moody5, Andy Barr7 and Peter Langridge7 , 1Plant Sciences, Faculty of Agriculture, UWA, 2Queensland Department of Primary Industries, Warwick, QLD,3Agriculture Western Australia, 4Centre for Plant Conservation Genetics, Southern Cross University, Lismore NSW, 5VIDA Private Bag 260, Horsham VIC, 6NSW Dept. of Agriculture, Wagga Wagga NSW, 7Department of Plant Science, University of Adelaide, Glen Osmond SA 38. Can we improve grain yield by breeding for greater early vigour in wheat? Tina Botwright1, Tony Condon1, Robin Wilson2 and Iain Barclay2, 1CSIRO Plant Industry, 2Agriculture Western Australia MARKETING AND QUALITY 39. The Crop Improvement Royalty, Howard Carr, Agriculture Western Australia 40. GrainGuardÔ - The development of a protection plan for the wheat industry, Greg Shea, Agriculture Western Australia CLIMATE 41. Rainfall – what happened in 2000 and the prospects for 2001, Ian Foster, Agriculture Western Australia 42. Software for climate management issues, David Tennant,Agriculture Western Australia CONTRIBUTING AUTHOR CONTACT DETAIL

Origin of leaf rust adult plant resistance gene Rph20 in barley

Rph20 is the only reported, simply inherited gene conferring moderate to high levels of adult plant resistance (APR) to leaf rust (Puccinia hordei Otth) in barley (Hordeum vulgare L.). Key parental genotypes were examined to determine the origin of Rph20 in two-rowed barley. The Dutch cultivar 'Vada' (released in the 1950s) and parents, 'Hordeum laevigatum' and 'Gull' ('Gold'), along with the related cultivar 'Emir' (a derivative of 'Delta'), were assessed for APR to P. hordei in a disease screening nursery. The marker bPb-0837-PCR, co-located with Rph20 on the short arm of chromosome 5H (5HS), was used to screen genotypes for the resistance allele, Rph20.ai. Results from phenotypic assessment and DNA analysis confirmed that Rph20 originated from the landrace 'H. laevigatum' (i.e., Hordeum vulgare subsp. vulgare). Tracing back this gene through the pedigrees of two-rowed barley cultivars, indicated that Rph20 has contributed APR to P. hordei for more than 60 years. Although there have been no reports of an Rph20-virulent pathotype, the search for alternative sources of APR should continue to avoid widespread reliance upon a single resistance factor

Genome-wide association mapping analysis to identify genomic regions associated with virulence in Pyrenophora teres f. teres

Net form of net blotch, caused by the fungal pathogen, Pyrenophora teres f. teres (Ptt), is an important foliar disease present in all barley (Hordeum vulgare) producing regions of the world. This fungus is a heterothallic haploid ascomycete and reproduces both sexually and asexually. Sexual recombination in Ptt can produce new combinations of pathogen virulences and lead to changes in disease expression in the host. Changes in virulence can be devastating to the barley industry especially if a limited number of barley varieties with common resistances are grown. Knowledge of the genetic structure and genes involved in virulence is vital to researchers and breeders to increase the durability of Ptt resistance in barley varieties. We have used a genome-wide association mapping approach to characterise genomic regions associated with virulence in Australian barley varieties. One hundred and eighty-seven Ptt isolates collected from five Australian states were genotyped using DArTseq (Diversity Arrays Technology Pty Ltd) markers and phenotyped across ten different barley genotypes. Association mapping analysis identified eleven unique genomic regions associated with virulence. The majority of these genomic regions were located on Ptt chromosomes 3 and 5. Four of the regions identified were confirmed via bi-parental quantitative trait loci mapping analysis in two different Ptt/Ptt populations. Knowledge of the virulence genes present in the Australian Ptt pathogen population will provide barley breeding programs with valuable information for future breeding of Ptt resistant barley varieties

The intrinsic and regulated proteomes of barley seeds in response to fungal infection

Barley is an important cereal grain used for beer brewing, animal feed, and human food consumption. Fungal disease can impact barley production, as it causes substantial yield loss and lowers seed quality. We used sequential window acquisition of all theoretical ions mass spectrometry (SWATH-MS) to measure and quantify the relative abundance of proteins within seeds of different barley varieties under various fungal pathogen burdens (ProteomeXchange Datasets PXD011303 and PXD014093). Fungal burden in the leaves and stems of barley resulted in changes to the seed proteome. However, these changes were minimal and showed substantial variation among barley samples infected with different pathogens. The limited effect of intrinsic disease resistance on the seed proteome is consistent with the main mediators of disease resistance being present in the leaves and stems of the plant. The seeds of barley varieties accredited for use as malt had higher levels of proteins associated with starch synthesis and beer quality. The proteomic workflows developed and implemented here have potential application in quality control, breeding and processing of barley, and other agricultural products

Genomic Regions Associated with Virulence in Pyrenophora teres f. teres Identified by Genome-Wide Association Analysis and Biparental Mapping

Net form net blotch (NFNB), caused by the fungal pathogen Pyrenophora teres f. teres, is an important foliar disease present in all barley-producing regions of the world. This fungus is a hemibiotrophic and heterothallic ascomycete, where sexual recombination can lead to changes in disease expression in the host. Knowledge of the genetic architecture and genes involved in virulence is vital to increase the durability of NFNB resistance in barley cultivars. We used a genome-wide association mapping approach to characterize P. teres f. teres genomic regions associated with virulence in Australian barley cultivars. One hundred eighty-eight P. teres f. teres isolates collected across five Australian states were genotyped using Diversity Arrays Technology sequence markers and phenotyped across 20 different barley genotypes. Association mapping identified 14 different genomic regions associated with virulence, with the majority located on P. teres f. teres chromosomes 3 and 5 and one each present on chromosomes 1, 6, and 9. Four of the regions identified were confirmed by quantitative trait loci (QTL) mapping. The QTL regions are discussed in the context of their genomic architecture together with examination of their gene contents, which identified 20 predicted effectors. The number of QTL shown in this study at the population level clearly illustrates a complex genetic basis of P. teres f. teres virulence compared with pure necrotrophs, such as the wheat pathogens Parastagonospora nodorum and Parastagonospora tritici-repentis

Methodology Development of Water Footprint Assessment Using GIS Technology – Study Area: Water District of Western Peloponnese (GR01)

To respond faster to the changing climate, evolving pathogens and to feed a global population of 9–10 billion by 2050, plant breeders are exploring more efficient crop improvement strategies. In this study, we applied novel methodology for rapid trait introgression to the European two-rowed barley cultivar Scarlett. Scarlett is widely-grown in Argentina and is preferred for malting and brewing, yet lacks adequate disease resistance. We used four donor lines combining multiple disease resistance (i.e. leaf rust, net and spot forms of net blotch and spot blotch) in a modified backcross strategy, which incorporated both multi-trait phenotypic screens and the rapid generation advance technology ‘speed breeding’, to develop 87 BC1F3:4 Scarlett introgression lines (ILs) within two years. Phenotyping this set of lines in disease nurseries located in Australia and Uruguay revealed the ILs had high levels of multiple disease resistance. Preliminary yield testing of the 12 most promising ILs in Argentina identified three ILs that were significantly higher yielding than Scarlett at Balcarce, whereas all 12 ILs displayed yield equivalent to Scarlett at Tres Arroyos. We propose that this approach is useful to rapidly transfer genes for multiple target traits into adapted cereal cultivars or pyramiding desirable traits in elite breeding material

Mapping quantitative trait loci for partial resistance to powdery mildew in an Australian barley population

Genomic regions influencing resistance to powdery mildew [Blumeria graminis (DC.) E.O. Speer f. sp. hordei Ém. Marchal] were detected in a doubled haploid (DH) barley (Hordeum vulgare L.) population derived from a cross between the breeding line ND24260 and cultivar Flagship when evaluated across four field environments in Australia and Uruguay. Significant quantitative trait loci (QTL) for resistance to B. graminis were detected on six of the seven chromosomes (1H, 2H, 3H, 4H, 5H, and 7H). A QTL with large effect donated by ND24260 mapped to the short arm of chromosome 1H (1HS) conferring near immunity to B. graminis in Australia but was ineffective in Uruguay. Three QTL donated by Flagship contributed partial resistance to B. graminis and were detected in at least two environments. These QTL were mapped to chromosomes 3H, 4H, and 5H (5HS) accounting for up to 18.6, 3.4, and 8.8% phenotypic variation, respectively. The 5HS QTL contributed partial resistance to B. graminis in all field environments in both Australia and Uruguay and aligned with the genomic region of Rph20, a gene conferring adult plant resistance (APR) to leaf rust (Puccinia hordei Otth), which is found in some cultivars having 'Vada' or 'Emir' in their parentage. Selection for favorable marker haplotypes within the 3H, 4H, and 5H QTL regions can be performed even in the presence of single (major) gene resistance. Pyramiding such QTL may provide an effective and potentially durable form of resistance to B. graminis