scholarly journals Virulence Pattern of Pyricularia oryzae Pathotypes Towards Blast Monogenic Lines

2021 ◽  
Vol 32 (3) ◽  
pp. 147-160
Author(s):  
Siti Norsuha Misman ◽  
Mohd Shahril Firdaus Ab Razak ◽  
Nur Syahirah Ahmad Sobri ◽  
Latiffah Zakaria
Keyword(s):  
Resistance Genes ◽  
Rice Blast ◽  
Blast Resistance ◽  
Rice Variety ◽  
Durable Resistance ◽  
Peninsular Malaysia ◽  
Pyricularia Oryzae ◽  
Blast Disease ◽  
Breeding Lines ◽  
Virulence Pattern

Rice blast caused by Pyricularia oryzae (P. oryzae) is one of the most serious diseases infecting rice worldwide. In the present study, virulence pattern of six P. oryzae pathotypes (P0.0, P0.2, P1.0, P3.0, P7.0 and P9.0) identified from the blast pathogen collected in Peninsular Malaysia, were evaluated using a set of 22 IRRI-bred blast resistance lines (IRBL) as well as to determine the resistance genes involved. The information on the virulence of the blast pathotypes and the resistance genes involved is important for breeding of new rice variety for durable resistance against blast disease. The IRBL was established from 22 monogenic lines, harbouring 22 resistance genes [Pia, Pib, Pii, Pit, Pi3, Pi5(t), Pish, Pi1, Pik, Pik-s, Pik-m, Pik-h, Pik-p, Pi7(t), Pi9, Piz, Piz-5, Piz-t, Pi19, Pi20(t), Pita-2, and Pita=Pi4(t)]. Based on the disease severity patterns, the tested pathotypes were avirulence towards seven IRBLs [IRBLi-F5, IRBLk-Ka, IRBLkh-K3, IRBLz-Fu, IRBLsh-S, IRBLPi7 (t) and IRBL9-W] of which these IRBLs harbouring Pii, Pik, Pik-h, Piz, Pish, Pi7(t) and Pi9 resistance genes, respectively. Therefore, the results suggested that the seven IRBLs carrying seven resistance genes [Pii, Pik, Pik-h, Piz, Pish, Pi7(t) and Pi9] would be suitable candidates of resistance genes to be incorporated in new breeding lines to combat the current blast pathotypes in the field.

scholarly journals A Genome-Wide Meta-Analysis of Rice Blast Resistance Genes and Quantitative Trait Loci Provides New Insights into Partial and Complete Resistance

2008 ◽  
Vol 21 (7) ◽  
pp. 859-868 ◽  
Author(s):  
Elsa Ballini ◽  
Jean-Benoît Morel ◽  
Gaétan Droc ◽  
Adam Price ◽  
Brigitte Courtois ◽  
...  
Keyword(s):  
Quantitative Trait Loci ◽  
Resistance Genes ◽  
Quantitative Trait ◽  
Rice Blast ◽  
Blast Resistance ◽  
Durable Resistance ◽  
Rice Genome ◽  
Blast Disease ◽  
Trait Loci ◽  
Blast Resistance Genes

The completion of the genome sequences of both rice and Magnaporthe oryzae has strengthened the position of rice blast disease as a model to study plant–pathogen interactions in monocotyledons. Genetic studies of blast resistance in rice were established in Japan as early as 1917. Despite such long-term study, examples of cultivars with durable resistance are rare, partly due to our limited knowledge of resistance mechanisms. A rising number of blast resistance genes and quantitative trait loci (QTL) have been genetically described, and some have been characterized during the last 20 years. Using the rice genome sequence, can we now go a step further toward a better understanding of the genetics of blast resistance by combining all these results? Is such knowledge appropriate and sufficient to improve breeding for durable resistance? A review of bibliographic references identified 85 blast resistance genes and approximately 350 QTL, which we mapped on the rice genome. These data provide a useful update on blast resistance genes as well as new insights to help formulate hypotheses about the molecular function of blast QTL, with special emphasis on QTL for partial resistance. All these data are available from the OrygenesDB database.

scholarly journals Study of pathogenicity and genetic diversity of Magnaporthe oryzae isolated from rice hybrid Wuyou 308 and detection of resistance genes

2020 ◽  
Vol 56 (No. 3) ◽  
pp. 93-101
Author(s):  
Bo Lan ◽  
Ying-Qing Yang ◽  
Qiang Sun ◽  
Hong-Fan Chen ◽  
Jian Chen ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Magnaporthe Oryzae ◽  
Rice Blast ◽  
Blast Resistance ◽  
Rice Variety ◽  
Climatic Conditions ◽  
Blast Disease ◽  
Rice Varieties ◽  
Rice Blast Resistance ◽  
Rice Hybrid

To understand the cause of loss of rice blast resistance, we studied the pathogenicity of Magnaporthe oryzae strains isolated from rice hybrid Wuyou 308 and evaluated its resistance genes. A total of 62 M. oryzae strains were isolated and tested in 7 Chinese rice varieties with varying degrees of resistance to rice blast and 30 blast-resistant monogenic lines. Fourteen physiological races of M. oryzae were identified: 8.55% belonging to the ZA group, 86.67% to the ZB group, and 5.00% to the ZC group. ZB15 was the most abundant race (45.00%). Five resistance genes, Pi-3(1), Pi-z5, Pi-k, Pi-kp(C), and Pi-k(C), conferred good resistance to the 62 strains, with resistance frequencies of 95.56, 91.11, 88.89, 82.22, and 82.22%, respectively. In contrast, Pi-a(2) had a resistance frequency of 0%. The hybrid combination Wuyou 308 was found to carry Pi-ta and Pi-b genes. Because Pi-ta and Pi-b both showed low resistance frequencies to M. oryzae isolated from Jiangxi, the hybrid rice variety Wuyou 308 could be infected by most of the 62 M. oryzae strains. The emergence and spread of rice blast disease in Wuyou 308 may thus be difficult to avoid when climatic conditions are favourable.

scholarly journals Two novel gene-specific markers at pik locus facilitate the application of rice blast resistant alleles in breeding

2019 ◽  
Author(s):  
Dagang Tian ◽  
Ziqiang Chen ◽  
Yan Lin ◽  
Zaijie Chen ◽  
Jiami Luo ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Rice Blast ◽  
Blast Resistance ◽  
Durable Resistance ◽  
Resistance Breeding ◽  
Blast Disease ◽  
Chromosome 11 ◽  
Rice Varieties ◽  
Breeding Programs ◽  
New Gene

Abstract Background: Rice blast disease, caused by Magnaporthe oryzae, is a major constraint for rice production in the world. Introgression of blast-durable resistance genes into high-yielding rice cultivars has been considered an agricultural priority in an effort to control the disease. The blast resistance Pik locus, located on chromosome 11, contains at least six important resistance genes, but these genes have not been widely employed in resistance breeding since existing markers hardly satisfy current breeding needs owing to their limited scope of application.Results: In the present study, two PCR-based markers, Pikp-Del and Pi1-In, were developed to target the specific InDel (insertion/deletion) of the Pik-p and Pi-1 genes, respectively. The two markers precisely distinguished Pik-p, Pi-1, and the K-type alleles at the Pik locus, which is a necessary element for functional genes from rice varieties. Conclusions:Two gene-specific markers of Pi-kp and Pi1 identified that only several old varieties contain the two genes, nearly half these varieties yet carry the K-type alleles. Therefore, these identified varieties can be new gene sources for developing blast resistant rice. The two newly developed markers should be highly useful for using Pi-kp, Pi1 and other resistance genes at the Pik locus in marker-assisted selection (MAS) breeding programs.

scholarly journals Level of Endogenous Jasmonate is Critical for Durable Broad-Spectrum Disease Resistance Against Rice Blast in a Japonica Rice Variety, Ziyu44

2021 ◽  
Author(s):  
Xingyu An ◽  
Hui Zhang ◽  
Jinlu Li ◽  
Rui Yang ◽  
Qianchun Zeng ◽  
...  
Keyword(s):  
Disease Resistance ◽  
Signaling Pathway ◽  
Broad Spectrum ◽  
Rice Blast ◽  
Blast Resistance ◽  
Rice Variety ◽  
Blast Disease ◽  
Japonica Rice ◽  
Mycelium Growth ◽  
Broad Spectrum Resistance

Abstract Background: The molecular mechanism of durable and broad-spectrum resistance to rice blast disease in japonica rice variety is still very little known. Ziyu44, a local japonica rice variety in Yunnan Province of China, has shown durable broad-spectrum blast resistance for more than 30 years, and provides an opportunity for us to explore the molecular basis of broad-spectrum resistance to rice blast in japonica rice variety.Methods and Results: We conducted a comparative study of mycelium growth, aposporium formation, the accumulation of salicylate(SA), jasmonate(JA) and H2O2, the expression of SA- and JA-associated genes between Ziyu44 and susceptible variety Jiangnanxiangnuo (JNXN) upon M. oryzae infection. We found that appressorium formation and invasive hyphae extention were greatly inhibited in Ziyu 44 leaves compared with that in JNXN leaves. Both Ziyu 44 and JNXN plants maintained high levels of baseline SA and did not show increased accumulation of SA after inoculation with M. oryzae, while the levels of baseline JA in Ziyu 44 and JNXN plants were relatively low, and the accumulation of JA exhibited markedly increased in Ziyu 44 plants upon M. oryzae infection. The expression levels of key genes involving JA and SA signaling pathway OsCOI1b, OsNPR1, OsMPK6 as well as pathogenesis-related (PR) genes OsPR1a, OsPR1b and OsPBZ1, were markedly up-regulated in Ziyu44. Conclusions: The level of endogenous JA is critical for synchronous activation of SA and JA signaling pathway, up-regulating PR gene expression and enhancing disease resistance against rice blast in Ziyu44.

Investigating the biology of rice blast disease and prospects for durable resistance

2021 ◽  
pp. 643-680
Author(s):  
Vincent M. Were ◽  
◽  
Nicholas J. Talbot ◽  
Keyword(s):  
Cell Biology ◽  
Rice Blast ◽  
Plant Pathogens ◽  
Blast Resistance ◽  
Durable Resistance ◽  
Rice Blast Disease ◽  
Blast Disease ◽  
Global Food Security ◽  
Major Resistance Genes ◽  
Effector Secretion

There are important biological process involved in rice blast disease that are now well-studied during the early events in plant infection which include: the cell biology of appressorium formation, the biology of invasive growth and effector secretion, the two distinct mechanisms of effector secretion, the nature of the plant-pathogen interface, PAMP-triggered immunity modulation by secreted effectors and effector-triggered immunity and blast resistance. The devastating losses caused by the blast fungus have been documented in most grasses, but this chapter discusses the use of major resistance genes to rice blast and wheat blast disease as an emerging threat to global food security. This chapter also highlights an emerging approach to breed for durable resistance to plant pathogens using gene editing technologies with an example: CRISPR-Cas9 mutagenesis of dominant S-genes for disease control.

Pathogenicity of Isolates of the Rice Blast Pathogen (Pyricularia oryzae) from Indonesia

Plant Disease ◽  
2020 ◽  
Author(s):  
Santoso Kadeawi ◽  
Suwarno Non ◽  
Anggiani Nasution ◽  
Aris Hairmansis ◽  
Mitsuhiro Obara ◽  
...  
Keyword(s):  
Differential System ◽  
Resistance Genes ◽  
Rice Blast ◽  
Pyricularia Oryzae ◽  
The Other ◽  
Blast Disease ◽  
Rice Cultivars ◽  
Rice Ecosystems ◽  
Susceptible Control ◽  
Differential Varieties

A total of 201 isolates of Pyricularia oryzae (the causal agent of rice blast) were collected from three rice ecosystems (upland, lowland, and swampy) in five regions of Indonesia (West Java, Lampung, South Sumatra, Kalimantan, and Bali). Their pathogenicities were characterized based on the patterns of reaction of 25 differential varieties (DVs) and the susceptible control Lijiangxintuanheigu (LTH), which was susceptible to all blast isolates. A high proportion of isolates (>80.0%) were virulent to DVs for resistance genes Pib, Pit, Pia, Pik-s, and Pi12(t), and a low proportion of isolates (<12.9%) were virulent to DVs for Pik-m, Pi1, Pik-h, Pik, Pik-p, and Pi7(t). Virulence to the other DVs for Pish, Pii, Pi3, Pi5(t), Pi9(t), Piz, Piz-5, Piz-t, Pita-2 (two lines), Pita (two lines), Pi19(t), and Pi20(t) showed intermediate frequencies from 20.0% to 80.0%. These isolates were classified into three cluster groups Ia, Ib, and II, and the frequencies of cluster groups varied among the three ecosystems and the five regions. The frequencies of cluster groups varied among the different ecosystems and regions, and races varied according to the ecosystems. A total of 27 standard differential blast isolates (SDBLs) were selected from the 201 isolates collected. The set of 25 DVs and these 27 SDBIs will be used as a new differential system for analysis of the pathogenicity of blast isolates and analysis of resistance genes in rice cultivars, which will contribute to building up a durable protection system against blast disease in Indonesia.

scholarly journals Diversity and Distribution of Rice Blast (Pyricularia oryzae Cavara) Races in Bangladesh

Plant Disease ◽  
2016 ◽  
Vol 100 (10) ◽  
pp. 2025-2033 ◽  
Author(s):  
M. A. I. Khan ◽  
M. A. Ali ◽  
M. A. Monsur ◽  
A. Kawasaki-Tanaka ◽  
N. Hayashi ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Resistance Genes ◽  
Rice Blast ◽  
Blast Resistance ◽  
Pyricularia Oryzae ◽  
Blast Protection ◽  
Blast Resistance Gene ◽  
Group I ◽  
Differential Varieties ◽  
Reaction Patterns

The pathogenicity of 331 blast isolates (Pyricularia oryzae Cavara) collected from different regions and ecosystems for rice cultivation in Bangladesh was evaluated by compatibility on 23 differential varieties (DV), each harboring a single blast resistance gene, and susceptible ‘Lijiangxintuanheigu’ (LTH). A wide variation in virulence was found among the isolates, and 267 races were classified using a new designation system. Virulence of blast isolates against DV carrying the resistance genes Pia, Pib, Pit, Pik-s, Piz-t, Pi12(t), Pi19(t), and Pi20(t), as well as avirulence against those carrying Pish, Pi9, Pita-2, and Pita, was distributed widely in Bangladesh. Cluster analysis of the compatibility data on the DV initially classified the isolates into groups I and II. The virulence spectra of the two groups differed mainly according to the reactions of the DV to Pii, Pi3, Pi5(t), Pik-m, Pi1, Pik-h, Pik, Pik-p, and Pi7(t). Group I isolates were distributed mainly in rainfed lowlands, whereas group II isolates were found mainly in irrigated lowlands; however, there were no critical differences in geographic distribution of the blast isolates. In total, 26 isolates, which could be used to identify the 23 resistance genes of the DV on the basis of their reaction patterns, were selected as a set of standard differential blast isolates. To our knowledge, this is the first clear demonstration of the diversity and differentiation of blast races in Bangladesh. This information will be used to develop a durable blast protection system in that country.

scholarly journals Development of blast resistant rice plants using CRISPR / Cas9 system for genome editing

2021 ◽  
Author(s):  
◽  
Fabiano Touzdjian Pinheiro Kohlrausch Távora
Keyword(s):  
Rice Blast ◽  
Blast Resistance ◽  
Rice Variety ◽  
Susceptibility Genes ◽  
Plant Diseases ◽  
Blast Disease ◽  
World Population ◽  
Japonica Rice ◽  
Rice Cultivars ◽  
Short Period

Rice (Oryza sativa L.) is the main food crop for more than half of the world population but unfortunately, it is severely affected by blast, one of the most widespread and devastating plant diseases, caused by the fungus Magnaporthe oryzae. Hence, the development of rice cultivars with greater resistance to blast is one of the main focuses of breeding programs. However, due to the complex biology of the pathogen, rice cultivars genetically resistant to the fungus become susceptible in a short period of time. In this context, the knockout of rice susceptibility genes represents a flourishing approach to obtain rice cultivars with a broader and longer-lasting resistance to M. oryzae. The present study aimed to use the genomic editing technology - CRISPR/Cas9 system, for knocking-out genes engaged with rice susceptibility to fungal infection. From previous transcriptomics results of two semi-isogenic rice lines - NILs infected by M. oryzae, potential rice-blast susceptibility genes were selected. The prospection of candidate genes for gene editing was complemented by a comparative shotgun proteomic analysis of the protein profile of the interaction between IRBLi-F5 (susceptible) and IRBL5-M (resistant) NILs in early stages of M. oryzae infection, that revealed a specific set of proteins potentially associated with susceptibility. After the characterization and validation of gene expression by RT-qPCR of the most prominent candidates, the target genes OsDjA2, OsERF104 and OsPyl5 were selected and submitted to a functional validation via gene silencing in planta, using antisense oligonucleotides (ASO), in which a clear reduction of leaf symptoms was observed in the compatible identification. Subsequently, the model japonica rice variety Nipponbare was transformed with simplex CRISPR/Cas9 vectors aiming to the independent knockout of each target gene. The T1 progeny of rice-edited plants, homozygous for the null (loss of function)-mutation were tested for blast resistance. As expected, mutant plants showed a decrease of disease symptoms in comparison with control lines (transformant non-edited plants). The results obtained in this study can contribute for the development of rice cultivars resistant to blast disease, besides shedding light on new potential rice-blast susceptibility genes.

scholarly journals The Pi40 Gene for Durable Resistance to Rice Blast and Molecular Analysis of Pi40-Advanced Backcross Breeding Lines

2009 ◽  
Vol 99 (3) ◽  
pp. 243-250 ◽  
Author(s):  
J. P. Suh ◽  
J. H. Roh ◽  
Y. C. Cho ◽  
S. S. Han ◽  
Y. G. Kim ◽  
...  
Keyword(s):  
Leaf Area ◽  
Resistance Genes ◽  
Rice Blast ◽  
Blast Resistance ◽  
Recurrent Parent ◽  
Diseased Leaf ◽  
Breeding Lines ◽  
Advanced Backcross ◽  
Diseased Leaf Area ◽  
Backcross Breeding

Rice blast severely reduces production in both irrigated and water-stressed upland ecosystems of tropical and temperate countries. Nearly 50 blast resistance genes have been identified and some of those are incorporated into several rice cultivars. However, most of the resistance genes break down in a few years because of their race specificity and the rapid change in pathogenicity of the blast fungus (Magnaporthe grisea). The objective of this study was to analyze advanced backcross breeding lines (ABL) possessing the gene Pi40 for durable rice blast resistance. In all, 4 resistant genotypes, 4 japonica cultivars, and 10 monogenic differential rice genotypes with some known resistance genes were bioassayed in the greenhouse using seven sequential plantings and 29 virulent M. grisea isolates of Korea. The genotypes with the Pi40 gene had <3% diseased leaf area, which was significantly below the disease threshold level of 40% considered for durable blast resistance. Moreover, the genotypes with the Pi40 gene expressed compatibility with only two to three virulent M. grisea isolates supporting durability of resistance, in contrast to susceptible cultivars with >50% diseased leaf area and 10 compatible isolates. Of the 10 known resistance genes tested, Piz-t, Piz-5, and Pi9 showed differential reactions to the pathogen isolates in seven plantings. Genotyping of the ABL with 260 simple sequence repeat (SSR) markers revealed rapid conversion toward recurrent parent genotypes with fewer donor chromosomal segments (5.3 to 14.5%). Our study based on a sequential testing and background selection of breeding lines with the resistance gene Pi40 provided valuable information for durable blast resistance breeding in rice.

scholarly journals Genotyping for Blast (Pyricularia oryzae) Resistance Genes in F2 Population of Supa Aromatic Rice (Oryza sativa L.)

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
L. Kanyange ◽  
J. Kamau ◽  
O. Ombori ◽  
A. Ndayiragije ◽  
M. Muthini
Keyword(s):  
Host Plants ◽  
Oryza Sativa L ◽  
Blast Resistance ◽  
Rice Variety ◽  
Snp Markers ◽  
Pyricularia Oryzae ◽  
Blast Disease ◽  
Aromatic Rice ◽  
R Genes ◽  
F2 Population

The ascomycete fungus, Pyricularia oryzae or Magnaporthe oryzae, is known to cause blast disease in more than 80 host plants of the Gramineae family—cereals including rice and grasses. The improvement of the Supa234 rice line (IR97012-27-3-1-1-B, containing badh2 gene for aroma) developed at IRRI-ESA Burundi consisted of introgression of R genes (Pita and Pi9) for blast resistance. The F2 population obtained via the cross had been screened for blast resistance using inoculation with Pyricularia oryzae spore’s suspension. The objectives of this study were to assess the presence of Pita and Pi9 genes for blast resistance and to assess the presence of the badh2 gene for aroma in the screened F2 plants using molecular markers. Genotyping was carried out in 103 F2 plants which grew to maturity using the KASP genotyping method with SNP markers (snpOS0007, snpOS0006, and snpOS0022) targeting the Pita and Pi9 genes for blast resistance and the badh2 gene for aromatic fragrance. The genotyping results showed that 38 F2 plants had the Pita gene present in both alleles, 31 F2 plants with the Pita gene in one allele, and only one plant (3B1) was found with the Pi9 gene in one allele. The badh2 gene for aroma was detected in 27 F2 plants on both alleles and in 57 F2 plants on one allele. There were thirteen plants which had both the Pita gene and the badh2 gene for aroma, and only one plant (3B1) had a combination of the three genes (Pita, Pi9, and badh2). Seven plants resistant to blast disease (2H2, 2H4, 1G2, 1C12, 1E13, 1B12, and 1C5) with the Pita and badh2 genes were found, and only one resistant plant (3B1) had a combination of the three genes Pi9, Pita, and badh2 which is recommended to be bulked for the development of the Supa aromatic rice variety resistant to blast disease. The plants generated by the best line 3B1 should further be evaluated for grain quality (Supa type) after F5 generation in the field.

Sign in / Sign up

Export Citation Format

Share Document