The ACE1 secondary metabolite gene cluster is a pathogenicity factor of wheat blast fungus.

Wheat blast caused by Pyricularia oryzae pathotype Triticum is now becoming a very serious threat to global food security. Here, we report an essential pathogenicity factor of the wheat blast fungus that is recognized and may be targeted by a rice resistance gene. Map-based cloning of Pwt2 showed that its functional allele is the ACE1 secondary metabolite gene cluster of the wheat blast fungus required for its efficient penetration of wheat cell walls.

Evolution of wheat blast resistance gene Rmg8 accompanied by differentiation of variants recognizing the powdery mildew fungus.

Wheat blast, a devastating disease having spread recently from South America to Asia and Africa, is caused by Pyricularia oryzae (synonym of Magnaporthe oryzae) pathotype Triticum, which first emerged in Brazil in 1985. Rmg8 and Rmg7, genes for resistance to wheat blast found in common wheat and tetraploid wheat, respectively, recognize the same avirulence gene, AVR-Rmg8. Here we show that an ancestral resistance gene, which had obtained an ability to recognize AVR-Rmg8 before the differentiation of Triticum and Aegilops, has expanded its target pathogens.

, a Novel Wheat Blast Resistance Gene Derived from .

Wheat blast, caused by (syn. ) pathotype (MoT), is a devastating disease that can result in up to 100% yield loss in affected fields. To find new resistance genes against wheat blast, we screened 199 accessions of , the D genome progenitor of common wheat (), by seedling inoculation assays with Brazilian MoT isolate Br48 and found 14 resistant accessions.

Breeding of a Near-Isogenic Wheat Line Resistant to Wheat Blast at Both Seedling and Heading Stages Through Incorporation of .

Wheat blast caused by pathotype (MoT) has been transmitted from South America to Bangladesh and Zambia and is now spreading in these countries. To prepare against its further spread to Asian countries, we introduced , a gene for resistance to wheat blast, into a Japanese elite cultivar, Chikugoizumi (ChI), through recurrent backcrosses and established ChI near-isogenic lines, #2-1-10 with the / genotype and #4-2-10 with the / genotype. A molecular analysis suggested that at least 96.

Identification of in Tetraploid Wheat as a New Blast Resistance Gene with Tolerance to High Temperature.

Wheat blast caused by pathotype has spread to Asia (Bangladesh) and Africa (Zambia) from the endemic region of South America. Wheat varieties with durable resistance are needed, but very limited resistance resources are currently available. After screening tetraploid wheat accessions, we found an exceptional accession St19 (, KU-114).

Correction: Genomic surveillance uncovers a pandemic clonal lineage of the wheat blast fungus.

[This corrects the article DOI: 10.1371/journal.pbio.

Loss of , Located on a Supernumerary Chromosome, Is Associated with Parasitic Specialization of on Wheat.

, a blast fungus of gramineous plants, is composed of various host genus-specific pathotypes. The avirulence of an isolate on wheat is conditioned by and . We isolated the third avirulence gene from the isolate and designated it as .

A wheat kinase and immune receptor form host-specificity barriers against the blast fungus.

Since emerging in Brazil in 1985, wheat blast has spread throughout South America and recently appeared in Bangladesh and Zambia. Here we show that two wheat resistance genes, Rwt3 and Rwt4, acting as host-specificity barriers against non-Triticum blast pathotypes encode a nucleotide-binding leucine-rich repeat immune receptor and a tandem kinase, respectively. Molecular isolation of these genes will enable study of the molecular interaction between pathogen effector and host resistance genes.

Disentangling the complex gene interaction networks between rice and the blast fungus identifies a new pathogen effector.

Studies focused solely on single organisms can fail to identify the networks underlying host-pathogen gene-for-gene interactions. Here, we integrate genetic analyses of rice (Oryza sativa, host) and rice blast fungus (Magnaporthe oryzae, pathogen) and uncover a new pathogen recognition specificity of the rice nucleotide-binding domain and leucine-rich repeat protein (NLR) immune receptor Pik, which mediates resistance to M. oryzae expressing the avirulence effector gene AVR-Pik.

Origin and Dynamics of , a Wheat Gene for Resistance to Nonadapted Pathotypes of .

Avirulence of isolates of on common wheat is conditioned by at least five avirulence genes. One is corresponding to resistance gene located on chromosome 1D. We identified a resistance gene corresponding to a second avirulence gene, , and named it ().

Correlation of Genomic Compartments with Contrastive Modes of Functional Losses of Host Specificity Determinants During Pathotype Differentiation in .

The specificity between pathotypes of and genera of gramineous plants is governed by gene-for-gene interactions. Here, we show that avirulence genes involved in this host specificity have undergone different modes of functional losses dependent on or affected by genomic compartments harboring them. The avirulence of an pathotype on wheat is controlled by five genes, including , which played a key role in the evolution of the pathotype (the wheat blast fungus).

Effectiveness of the Wheat Blast Resistance Gene in Bangladesh Suggested by Distribution of an Allele in the Population.

Wheat blast caused by the pathotype of was first reported in 1985 in Brazil and recently spread to Bangladesh. We tested whether and , recently identified resistance genes, were effective against Bangladeshi isolates of the pathogen. Common wheat accessions carrying alone (IL191) or both and (GR119) were inoculated with Brazilian isolates (Br48, Br5, and Br116.

Suppression of wheat blast resistance by an effector of Pyricularia oryzae is counteracted by a host specificity resistance gene in wheat.

Wheat blast caused by the Triticum pathotype of Pyricularia oryzae poses a serious threat to wheat production in South America and Asia and is now becoming a pandemic disease. Here, we show that Rmg8, a promising wheat gene for resistance breeding, is suppressed by PWT4, an effector gene of P. oryzae, and in turn that the suppression is counteracted by Rwt4, a wheat gene recognizing PWT4.

At Least Five Major Genes Are Involved in the Avirulence of an Isolate of on Common Wheat.

is composed of pathotypes that show host specificity at the plant genus level. To elucidate the genetic mechanisms of the incompatibility between the pathotype (pathogenic on finger millet) and common wheat, an isolate (MZ5-1-6) was crossed with a isolate (Br48) pathogenic on wheat, and resulting F cultures were sprayed onto common wheat cultivars Hope, Norin 4 (N4), and Chinese Spring (CS). On Hope, avirulent and virulent cultures segregated in a 3:1 ratio, suggesting that two avirulence genes are involved.

Evolution of an -Specific Subgroup of Through a Gain of an Avirulence Gene.

isolates (members of the pathotype) of are divided into two subgroups, EC-I and EC-II, differentiated by molecular markers. A multilocus phylogenetic analysis revealed that these subgroups are very close to isolates. EC-II and isolates were exclusively virulent on finger millet and weeping lovegrass, respectively, while EC-I isolates were virulent on both.

Blast Fungal Genomes Show Frequent Chromosomal Changes, Gene Gains and Losses, and Effector Gene Turnover.

Pyricularia is a fungal genus comprising several pathogenic species causing the blast disease in monocots. Pyricularia oryzae, the best-known species, infects rice, wheat, finger millet, and other crops. As past comparative and population genomics studies mainly focused on isolates of P.

A New Resistance Gene in Combination with Rmg8 Confers Strong Resistance Against Triticum Isolates of Pyricularia oryzae in a Common Wheat Landrace.

The wheat blast fungus (Triticum pathotype of Pyricularia oryzae) first arose in Brazil in 1985 and has recently spread to Asia. Resistance genes against this new pathogen are very rare in common wheat populations. We screened 520 local landraces of common wheat collected worldwide with Br48, a Triticum isolate collected in Brazil, and found a highly resistant, unique accession, GR119.

Rmg8 and Rmg7, wheat genes for resistance to the wheat blast fungus, recognize the same avirulence gene AVR-Rmg8.

Rmg8 and Rmg7 are genes for resistance to the wheat blast fungus (Pyricularia oryzae), located on chromosome 2B in hexaploid wheat and chromosome 2A in tetraploid wheat, respectively. AVR-Rmg8, an avirulence gene corresponding to Rmg8, was isolated from a wheat blast isolate through a map-based strategy. The cloned fragment encoded a small protein containing a putative signal peptide.

Evolution of the wheat blast fungus through functional losses in a host specificity determinant.

Wheat blast first emerged in Brazil in the mid-1980s and has recently caused heavy crop losses in Asia. Here we show how this devastating pathogen evolved in Brazil. Genetic analysis of host species determinants in the blast fungus resulted in the cloning of avirulence genes and , whose gene products elicit defense in wheat cultivars containing the corresponding resistance genes and Studies on avirulence and resistance gene distributions, together with historical data on wheat cultivation in Brazil, suggest that wheat blast emerged due to widespread deployment of wheat (susceptible to isolates), followed by the loss of function of This implies that the wheat served as a springboard for the host jump to common wheat.

Generic names in Magnaporthales.

The order Magnaporthales comprises about 200 species and includes the economically and scientifically important rice blast fungus and the take-all pathogen of cereals, as well as saprotrophs and endophytes. Recent advances in phylogenetic analyses of these fungi resulted in taxonomic revisions. In this paper we list the 28 currently accepted genera in Magnaporthales with their type species and available gene and genome resources.

Host specialization of the blast fungus Magnaporthe oryzae is associated with dynamic gain and loss of genes linked to transposable elements.

Background: Magnaporthe oryzae (anamorph Pyricularia oryzae) is the causal agent of blast disease of Poaceae crops and their wild relatives. To understand the genetic mechanisms that drive host specialization of M. oryzae, we carried out whole genome resequencing of four M.

Rmg8, a New Gene for Resistance to Triticum Isolates of Pyricularia oryzae in Hexaploid Wheat.

Blast, caused by Pyricularia oryzae, is one of the major diseases of wheat in South America. We identified a new gene for resistance to Triticum isolates of P. oryzae in common wheat 'S-615', and designated it "resistance to Magnaporthe grisea 8" (Rmg8).

Rmg7, a New Gene for Resistance to Triticum Isolates of Pyricularia oryzae Identified in Tetraploid Wheat.

A single gene for resistance, designated Rmg7 (Resistance to Magnaporthe grisea 7), was identified in a tetraploid wheat accession, St24 (Triticum dicoccum, KU120), against Br48, a Triticum isolate of Pyricularia oryzae. Two other wheat accessions, St17 (T. dicoccum, KU112) and St25 (T.