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Mather D, Vassos E, Sheedy J, Guo W, McKay A. A Quantitative Trait Locus with a Major Effect on Root-Lesion Nematode Resistance in Barley. PLANTS (BASEL, SWITZERLAND) 2024; 13:1663. [PMID: 38931094 PMCID: PMC11207570 DOI: 10.3390/plants13121663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 06/11/2024] [Accepted: 06/13/2024] [Indexed: 06/28/2024]
Abstract
Although the root-lesion nematode Pratylenchus thornei is known to affect barley (Hordeum vulgare L.), there have been no reports on the genetic control of P. thornei resistance in barley. In this research, P. thornei resistance was assessed for a panel of 46 barley mapping parents and for two mapping populations (Arapiles/Franklin and Denar/Baudin). With both populations, a highly significant quantitative trait locus (QTL) was mapped at the same position on the long arm of chromosome 7H. Single-nucleotide polymorphisms (SNPs) in this region were anchored to an RGT Planet pan-genome assembly and assayed on the mapping parents and other barley varieties. The results indicate that Arapiles, Denar, RGT Planet and several other varieties likely have the same resistance gene on chromosome 7H. Marker assays reported here could be used to select for P. thornei resistance in barley breeding. Analysis of existing barley pan-genomic and pan-transcriptomic data provided a list of candidate genes along with information on the expression and differential expression of some of those genes in barley root tissue. Further research is required to identify a specific barley gene that affects root-lesion nematode resistance.
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Affiliation(s)
- Diane Mather
- School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA 5005, Australia;
| | - Elysia Vassos
- School of Agriculture, Food and Wine, Waite Research Institute, The University of Adelaide, Adelaide, SA 5005, Australia;
| | - Jason Sheedy
- Centre for Crop Health, University of Southern Queensland, Toowoomba, QLD 4350, Australia;
| | - Wenbin Guo
- Information and Computational Sciences, The James Hutton Institute, Dundee DD2 5DA, UK;
| | - Alan McKay
- South Australian Research and Development Institute, Adelaide, SA 5001, Australia;
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Guo J, Zhao C, Gupta S, Platz G, Snyman L, Zhou M. Genome-wide association mapping for seedling and adult resistance to powdery mildew in barley. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2024; 137:50. [PMID: 38363421 PMCID: PMC10873221 DOI: 10.1007/s00122-024-04550-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 01/10/2024] [Indexed: 02/17/2024]
Abstract
KEY MESSAGE Two new major QTL were identified for powdery mildew resistance. We confirmed that the QTL on 7HS contributed mainly to the adult-plant resistance, while another one on chromosome arm 1HS made a significant contribution to the seedling resistance. Powdery mildew (PM), caused by Blumeria hordei, can occur at all post emergent stages of barley and constantly threatens crop production. To identify more genes for effective resistance to powdery mildew for use in breeding programs, 696 barley accessions collected from different regions of the world were evaluated for PM resistance at seedling and adult growth stages in three different states of Australia. These barley accessions were genotyped using DArTSeq with over 18,000 markers for a genome-wide association study (GWAS). Using the FarmCPU model, 54 markers showed significant associations with PM resistance scored at the seedling and adult-plant stages in different states of Australia. Another 40 markers showed tentative associations (LOD > 4.0) with resistance. These markers are distributed across all seven barley chromosomes. Most of them were grouped into eleven QTL regions, coinciding with the locations of most of the reported resistance genes. Two major MTAs were identified on chromosome arms 3HS and 5HL, with one on 3HS contributing to adult plant resistance and the one on 5HL to both seedling and adult plant resistance. An MTA on 7HS contributed mainly to the adult-plant resistance, while another one on chromosome arm 1HS made a significant contribution to the seedling resistance.
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Affiliation(s)
- Jie Guo
- College of Agronomy, Shanxi Agricultural University, Jinzhong, 030801, China
| | - Chenchen Zhao
- Tasmanian Institute of Agriculture, University of Tasmania, Launceston, TAS, 7250, Australia
| | - Sanjiv Gupta
- Western Crop Genetics Alliance, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, 6150, Australia
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Greg Platz
- Department of Agriculture and Fisheries, Hermitage Research Facility, Warwick, QLD, 4370, Australia
| | - Lisle Snyman
- Department of Agriculture and Fisheries, Hermitage Research Facility, Warwick, QLD, 4370, Australia
| | - Meixue Zhou
- College of Agronomy, Shanxi Agricultural University, Jinzhong, 030801, China.
- Tasmanian Institute of Agriculture, University of Tasmania, Launceston, TAS, 7250, Australia.
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3
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Esmail SM, Jarquín D, Börner A, Sallam A. Genome-wide association mapping highlights candidate genes and immune genotypes for net blotch and powdery mildew resistance in barley. Comput Struct Biotechnol J 2023; 21:4923-4932. [PMID: 37867969 PMCID: PMC10585327 DOI: 10.1016/j.csbj.2023.10.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 10/08/2023] [Accepted: 10/08/2023] [Indexed: 10/24/2023] Open
Abstract
Net blotch (NB) and powdery mildew (PM) are major barley diseases with the potential to cause a dramatic loss in grain yield. Breeding for resistant barley genotypes in combination with identifying candidate resistant genes will accelerate the genetic improvement for resistance to NB and PM. To address this challenge, a set of 122 highly diverse barley genotypes from 34 countries were evaluated for NB and PM resistance under natural infection for in two growing seasons. Moreover, four yield traits; plant height (Ph), spike length (SL), spike weight (SW), and the number of spikelets per spike (NOS) were recorded. High genetic variation was found among genotypes in all traits scored in this study. No significant phenotypic correlation was found in the resistance between PM and NB. Immune genotypes for NB and PM were identified. A total of 21 genotypes were immune to both diseases. Of the 21 genotypes, the German genotype HOR_9570 was selected as the most promising genotype that can be used for future breeding programs. Furthermore, a genome-wide association study (GWAS) was used to identify resistant alleles to PM and NB. The results of GWAS revealed a set of 14 and 25 significant SNPs that were associated with increased resistance to PM and NB, respectively. This study provided very important genetic resources that are highly resistant to the Egyptian PM and NB pathotypes and revealed SNP markers that can be utilized to genetically improve resistance to PM and NB.
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Affiliation(s)
- Samar M. Esmail
- Wheat Disease Research Department, Plant Pathology Research Institute, Agricultural Research Center, Giza, Egypt
| | - Diego Jarquín
- Department of Agronomy, University of Florida, Gainesville, FL 32611, USA
| | - Andreas Börner
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany
| | - Ahmed Sallam
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), 06466 Gatersleben, Germany
- Department of Genetics, Faculty of Agriculture, Assiut University, 71526 Assiut, Egypt
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4
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Ge C, Wentzel E, D'Souza N, Chen K, Oliver RP, Ellwood SR. Adult resistance genes to barley powdery mildew confer basal penetration resistance associated with broad-spectrum resistance. THE PLANT GENOME 2021; 14:e20129. [PMID: 34392613 DOI: 10.1002/tpg2.20129] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 05/27/2021] [Indexed: 06/13/2023]
Abstract
Powdery mildew isa major disease of barley (Hordeum vulgare L.) for which breeders have traditionally relied on dominant, pathogen race-specific resistance genes for genetic control. Directional selection pressures in extensive monocultures invariably result in such genes being overcome as the pathogen mutates to evade recognition. This has led to a widespread reliance on fungicides and a single broad-spectrum recessive resistance provided by the mlo gene. The range of resistance genes and alleles found in wild crop relatives and landraces has been reduced in agricultural cultivars through an erosion of genetic diversity during domestication and selective breeding. Three novel major-effect adult plant resistance (APR) genes from landraces, designated Resistance to Blumeria graminis f. sp. hordei (Rbgh1 to Rbgh3), were identified in the terminal regions of barley chromosomes 5HL, 7HS, and 1HS, respectively. The phenotype of the new APR genes showed neither pronounced penetration resistance, nor the spontaneous necrosis and mesophyll cell death typical of mlo resistance, nor a whole epidermal cell hypersensitive response, typical of race-specific resistance. Instead, resistance was localized to the site of attempted penetration in an epidermal cell and was associated with cell wall appositions and cytosolic vesicle-like bodies, and lacked strong induction of reactive oxygen species. The APR genes exhibited differences in vesicle-like body sizes, their distribution, and the extent of localized 3,3-diaminobenzidine staining in individual doubled haploid lines. The results revealed a set of unique basal penetration resistance genes that offer opportunities for combining different resistance mechanisms in breeding programs for robust mildew resistance.
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Affiliation(s)
- Cynthia Ge
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
| | - Elzette Wentzel
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
| | - Nola D'Souza
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
| | - Kefei Chen
- Statistics for the Australian Grains Industry-West, School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
| | - Richard P Oliver
- School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
| | - Simon R Ellwood
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin Univ., Bentley, WA, 6102, Australia
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Dreiseitl A. A novel way to identify specific powdery mildew resistance genes in hybrid barley cultivars. Sci Rep 2020; 10:18930. [PMID: 33144630 PMCID: PMC7641246 DOI: 10.1038/s41598-020-75978-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 10/14/2020] [Indexed: 01/09/2023] Open
Abstract
Powdery mildew, a common cereal disease caused by the fungus Blumeria graminis, is a major limiting factor of barley production and genetic resistance is the most appropriate protection against it. To aid the breeding of new cultivars and their marketing, resistance genes can be postulated in homogeneous accessions. Although hybrid cultivars (F1) should be homogeneous, they are often not genetically uniform, especially if more than two genotypes are involved in their seed production or due to undesirable self-pollination, out-crossing and mechanical admixtures. To overcome these problems the accepted method of postulating specific resistance genes based on comparing response type arrays (RTAs) of genetically homogeneous cultivars with RTAs of standard genotypes was substituted by analysing the frequency of response types to clusters of pathogen isolates in segregating F2 generations. This method combines a genetic and phytopathological approach for identifying resistance genes. To assess its applicability six hybrid cultivars were screened and from three to seven with a total of 14 resistance genes were found. Two genes were newly located at the Mla locus and their heritability determined. In addition, three unknown dominant genes were detected. This novel, comprehensive and efficient method to identifying resistance genes in hybrid cultivars can also be applied in other cereals and crops.
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Affiliation(s)
- Antonín Dreiseitl
- Department of Integrated Plant Protection, Agrotest Fyto Ltd, Kroměříž, Czech Republic.
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6
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Dreiseitl A. Specific Resistance of Barley to Powdery Mildew, Its Use and Beyond. A Concise Critical Review. Genes (Basel) 2020; 11:E971. [PMID: 32825722 PMCID: PMC7565388 DOI: 10.3390/genes11090971] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/12/2020] [Accepted: 08/20/2020] [Indexed: 11/18/2022] Open
Abstract
Powdery mildew caused by the airborne ascomycete fungus Blumeria graminis f. sp. hordei (Bgh) is one of most common diseases of barley (Hordeum vulgare). This, as with many other plant pathogens, can be efficiently controlled by inexpensive and environmentally-friendly genetic resistance. General requirements for resistance to the pathogens are effectiveness and durability. Resistance of barley to Bgh has been studied intensively, and this review describes recent research and summarizes the specific resistance genes found in barley varieties since the last conspectus. Bgh is extraordinarily adaptable, and some commonly recommended strategies for using genetic resistance, including pyramiding of specific genes, may not be effective because they can only contribute to a limited extent to obtain sufficient resistance durability of widely-grown cultivars. In spring barley, breeding the nonspecific mlo gene is a valuable source of durable resistance. Pyramiding of nonspecific quantitative resistance genes or using introgressions derived from bulbous barley (Hordeum bulbosum) are promising ways for breeding future winter barley cultivars. The utilization of a wide spectrum of nonhost resistances can also be adopted once practical methods have been developed.
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Affiliation(s)
- Antonín Dreiseitl
- Department of Integrated Plant Protection, Agrotest Fyto Ltd., Havlíčkova 2787, CZ-767 01 Kroměříž, Czech Republic
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Pogoda M, Liu F, Douchkov D, Djamei A, Reif JC, Schweizer P, Schulthess AW. Identification of novel genetic factors underlying the host-pathogen interaction between barley (Hordeum vulgare L.) and powdery mildew (Blumeria graminis f. sp. hordei). PLoS One 2020; 15:e0235565. [PMID: 32614894 PMCID: PMC7332009 DOI: 10.1371/journal.pone.0235565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/18/2020] [Indexed: 12/12/2022] Open
Abstract
Powdery mildew is an important foliar disease of barley (Hordeum vulgare L.) caused by the biotrophic fungus Blumeria graminis f. sp. hordei (Bgh). The understanding of the resistance mechanism is essential for future resistance breeding. In particular, the identification of race-nonspecific resistance genes is important because of their regarded durability and broad-spectrum activity. We assessed the severity of powdery mildew infection on detached seedling leaves of 267 barley accessions using two poly-virulent isolates and performed a genome-wide association study exploiting 201 of these accessions. Two-hundred and fourteen markers, located on six barley chromosomes are associated with potential race-nonspecific Bgh resistance or susceptibility. Initial steps for the functional validation of four promising candidates were performed based on phenotype and transcription data. Specific candidate alleles were analyzed via transient gene silencing as well as transient overexpression. Microarray data of the four selected candidates indicate differential regulation of the transcription in response to Bgh infection. Based on our results, all four candidate genes seem to be involved in the responses to powdery mildew attack. In particular, the transient overexpression of specific alleles of two candidate genes, a potential arabinogalactan protein and the barley homolog of Arabidopsis thaliana’s Light-Response Bric-a-Brac/-Tramtrack/-Broad Complex/-POxvirus and Zinc finger (AtLRB1) or AtLRB2, were top candidates of novel powdery mildew susceptibility genes.
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Affiliation(s)
- Maria Pogoda
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Fang Liu
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Dimitar Douchkov
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Armin Djamei
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Jochen C. Reif
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Patrick Schweizer
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - Albert W. Schulthess
- Department of Breeding Research, Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
- * E-mail:
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8
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Wang Y, Xu Y, Gupta S, Zhou Y, Wallwork H, Zhou G, Broughton S, Zhang XQ, Tan C, Westcott S, Moody D, Sun D, Loughman R, Zhang W, Li C. Fine mapping QSc.VR4, an effective and stable scald resistance locus in barley (Hordeum vulgare L.), to a 0.38-Mb region enriched with LRR-RLK and GLP genes. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:2307-2321. [PMID: 32405768 DOI: 10.1007/s00122-020-03599-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
An effective and stable quantitative resistance locus, QSc.VR4, was fine mapped, characterized and physically anchored to the short arm of 4H, conferring adult plant resistance to the fungus Rhynchosporium commune in barley. Scald caused by Rhynchosporium commune is one of the most destructive barley diseases worldwide. Accumulation of adult plant resistance (APR) governed by multiple resistance alleles is predicted to be effective and long-lasting against a broad spectrum of pathotypes. However, the molecular mechanisms that control APR remain poorly understood. Here, quantitative trait loci (QTL) analysis of APR and fine mapping were performed on five barley populations derived from a common parent Vlamingh, which expresses APR to scald. Two QTLs, designated QSc.VR4 and QSc.BR7, were detected from a cross between Vlamingh and Buloke. Our data confirmed that QSc.VR4 is an effective and stable APR locus, residing on the short arm of chromosome 4H, and QSc.BR7 derived from Buloke may be an allele of reported Rrs2. High-resolution fine mapping revealed that QSc.VR4 is located in a 0.38 Mb genomic region between InDel markers 4H2282169 and 4H2665106. The gene annotation analysis and sequence comparison suggested that a gene cluster containing two adjacent multigene families encoding leucine-rich repeat receptor kinase-like proteins (LRR-RLKs) and germin-like proteins (GLPs), respectively, is likely contributing to scald resistance. Adult plant resistance (APR) governed by QSc.VR4 may confer partial levels of resistance to the fungus Rhynchosporium commune and, furthermore, be an important resource for gene pyramiding that may contribute broad-based and more durable resistance.
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Affiliation(s)
- Yonggang Wang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Yanhao Xu
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, China
| | - Sanjiv Gupta
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Yi Zhou
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, China
| | - Hugh Wallwork
- South Australian Research and Development Institute, Hartley Grove, Urrbrae, SA, Australia
| | - Gaofeng Zhou
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Sue Broughton
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Xiao-Qi Zhang
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Cong Tan
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
| | - Sharon Westcott
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - David Moody
- InterGrain Pty Ltd, South Perth, WA, Australia
| | - Dongfa Sun
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, China
| | - Robert Loughman
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Wenying Zhang
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, China.
| | - Chengdao Li
- Western Barley Genetics Alliance, Western Australian State Agricultural Biotechnology Centre, School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, Australia.
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, China.
- Agriculture and Food, Department of Primary Industries and Regional Development, South Perth, WA, Australia.
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Dinh HX, Singh D, Periyannan S, Park RF, Pourkheirandish M. Molecular genetics of leaf rust resistance in wheat and barley. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:2035-2050. [PMID: 32128617 DOI: 10.1007/s00122-020-03570-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/18/2020] [Indexed: 06/10/2023]
Abstract
The demand for cereal grains as a main source of energy continues to increase due to the rapid increase in world population. The leaf rust diseases of cereals cause significant yield losses, posing challenges for global food security. The deployment of resistance genes has long been considered as the most effective and sustainable way to control cereal leaf rust diseases. While genetic resistance has reduced the impact of these diseases in agriculture, losses still occur due to the ability of the respective rust pathogens to change and render resistance genes ineffective plus the slow pace at which resistance genes are discovered and characterized. This article highlights novel recently developed strategies based on advances in genome sequencing that have accelerated gene isolation by overcoming the complexity of cereal genomes. The leaf rust resistance genes cloned so far from wheat and barley belong to various protein families, including nucleotide binding site/leucine-rich repeat receptors and transporters. We review recent studies that are beginning to reveal the defense mechanisms conferred by the leaf rust resistance genes identified to date in cereals and their roles in either pattern-triggered immunity or effector-triggered immunity.
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Affiliation(s)
- Hoan X Dinh
- Plant Breeding Institute, Faculty of Science, The University of Sydney, Cobbitty, NSW, 2570, Australia
| | - Davinder Singh
- Plant Breeding Institute, Faculty of Science, The University of Sydney, Cobbitty, NSW, 2570, Australia
| | - Sambasivam Periyannan
- CSIRO Agriculture and Food, Box 1700, Clunies Ross Street, Canberra, 2601, Australia
| | - Robert F Park
- Plant Breeding Institute, Faculty of Science, The University of Sydney, Cobbitty, NSW, 2570, Australia.
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