Resistance in Rice Breeding Lines to the Blast Fungus in Nepal

A total of 36 rice breeding lines including checks were evaluated for resistance to blast atRampur during 2000-2001. The experiments were conducted under both field condition andgreenhouse inoculated condition. Qualitative resistance in rice to blast was assessed based onlesion type, whereas quantitative resistance was assessed based on area under disease progresscurve (AUDPC) in the upland field condition. The number of sporulating lesions and the numberof leaves with at least one sporulating lesion per plant were considered as measures forevaluation of quantitative resistance in the greenhouse assay. The lesion type, neck blastpercentage and AUDPC data suggest that most of the rice lines possess higher level of resistanceto leaf and neck blast. The rice lines varied for the number of sporulating lesions and the numberof leaves with sporulating lesion per plant. Some lines were incompatible to virulent blastisolates, showing major resistance genes. NR 1558, NR 601-1-1-9, BW306-2 and CN 836-3-10were promising lines for quantitative resistance to both leaf and neck blast. Radha 12, Sabitri,Janaki possess higher level of quantitative resistance to blast, hence these could be promoted forcultivation in blast-prone environments. These genotypes could also be utilized as donor parentsfor breeding durable blast resistant varieties. The most virulent blast isolate could be used forevaluation of both qualitative and quantitative resistance to blast in early generation in thegreenhouse so that workload could be cut down in future works.Key words: Blast resistance; field condition; greenhouse assay; Pyricularia grisea; rice linesDOI: 10.3126/narj.v6i0.3344Nepal Agriculture Research Journal Vol.6 2005 pp.49-56

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Reaction of Different Rice Lines Against Leaf and Neck Blast under Field Condition Of Chitwan Valley

Journal of the Institute of Agriculture and Animal Science ◽

10.3126/jiaas.v27i0.693 ◽

2006 ◽

Vol 27 ◽

pp. 37-44 ◽

Cited By ~ 1

Author(s):

KD Puri ◽

SM Shrestha ◽

KD Joshi ◽

GB KC

Keyword(s):

Field Condition ◽

Rice Blast ◽

Blast Resistance ◽

Blast Disease ◽

Resistant Variety ◽

Pyricularia Grisea ◽

Leaf Blast ◽

Neck Blast ◽

Chitwan Valley ◽

Moderately Resistant

The severity of the rice blast disease (Pyricularia grisea) of both leaf and neck varies with different environment and it becomes destructive under favorable condition. The leaf and neck blast resistance and susceptible interaction of 30 different tropical rice lines were evaluated under low-, mid- and up-land conditions of Chitwan district and classified on the basis of disease severity with respect to susceptible check, Masuli. Of them, 5, 10, 12 and 3 rice lines were resistant to leaf blast, moderately resistant, moderately susceptible susceptible, respectively. Similarly, for the neck blast nine lines were resistant, thirteen moderately resistant, seven moderately susceptible and one was susceptible. The progenies from Masuli/MT4 had the highest leaf and neck blast susceptible reaction, while the most of progenies from IPB (Irradiated Pusa Basmati), KalinghaIII_IR64, Radha 32_ KIII and Masuli_IR64 were resistant, and the most promising sources against leaf and neck blast resistance. Therefore, the progenies from these parents can be used in breeding the resistant variety. Key words: Pyricularia grisea, resistance, rice lines J. Inst. Agric. Anim. Sci. 27:37-44 (2006)

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Using microsatellite markers to select blast resistance in U.S. rice breeding lines

Rice Genetics Collection - Rice Genetics II ◽

10.1142/9789812814319_0097 ◽

2008 ◽

pp. 255-257

Author(s):

R. G. Fjellstrom ◽

C. Conaway ◽

W. D. Park ◽

M. A. Marchetti ◽

A. M. McClung

Keyword(s):

Microsatellite Markers ◽

Blast Resistance ◽

Rice Breeding ◽

Breeding Lines

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Epistasis and Quantitative Resistance to Pyricularia oryzae Revealed by GWAS in Advanced Rice Breeding Populations

10.21203/rs.2.22084/v1 ◽

2020 ◽

Author(s):

Juan Eduardo Rosas ◽

Maia Escobar ◽

Sebastián Martínez ◽

Pedro Blanco ◽

Fernando Pérez ◽

...

Keyword(s):

Genetic Background ◽

Blast Resistance ◽

Quantitative Resistance ◽

Major Effect ◽

Inbred Lines ◽

Phenotypic Variance ◽

Rice Breeding ◽

Tropical Japonica ◽

Breeding Populations ◽

Multilocus Model

Abstract Background: Rice blast caused by Pyricularia oryzae is a major rice disease worldwide. Despite the detailed knowledge on major resistance genes available to date, little is known about how these genes interact with quantitative blast resistance loci and with the genetic background. Knowledge on these interactions is crucial for assessing the usefulness of introgressed resistance loci in breeding germplasm. Our goal was to identify blast resistance loci in rice breeding populations and to describe how they interact among each other and with the genetic background. To that end, resistance to blast was mapped in two advanced rice breeding populations, one made of 305 indica type inbred lines, and the other of 245 tropical japonica inbred lines. The interactions and main effects of blast resistance loci were assessed in a multilocus model. Results: Well known, major effect blast resistance gene clusters were detected in both tropical japonica (Pii/Pi3/Pi5) and indica (Piz/Pi2/Pi9) populations with the GWAS scan 1. When these major effect loci were included as fixed cofactors in subsequent GWAS scans 2 and 3, additional QTL and more complex genetic architectures were revealed. The multilocus model for the tropical japonica population showed that Pii/Pi3/Pi5 had significant interaction with two QTL in chromosome 1 and one QTL in chromosome 8, together explaining 64% of the phenotypic variance. In the indica population a significant interaction among the QTL in chromosomes 6 and 4 and the genetic background, together with Piz/Pi2/Pi9 and QTL in chromosomes 1, 4 and 7, explained 35% of the phenotypic variance.Conclusions: Our results suggest that epistatic interactions can play a major role modulating the effect of major effect blast resistance loci such as Pii/Pi3/Pi5. Furthermore, the additive and epistatic effects of multiple QTL bring additional layers of quantitative resistance with a magnitude comparable to that of major effect loci. These findings highlight the need of genetic background-specific validation of markers for molecular assisted blast resistance breeding and provide insights for developing quantitative resistance to blast disease in rice.

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Epistasis and Quantitative Resistance to Pyricularia oryzae Revealed by GWAS in Advanced Rice Breeding Populations

Agriculture ◽

10.3390/agriculture10120622 ◽

2020 ◽

Vol 10 (12) ◽

pp. 622

Author(s):

Juan E. Rosas ◽

Maia Escobar ◽

Sebastián Martínez ◽

Pedro Blanco ◽

Fernando Pérez ◽

...

Keyword(s):

Genetic Background ◽

Blast Resistance ◽

Quantitative Resistance ◽

Major Effect ◽

Inbred Lines ◽

Phenotypic Variance ◽

Rice Breeding ◽

Tropical Japonica ◽

Breeding Populations ◽

Multilocus Model

Rice blast caused by Pyricularia oryzae is a major rice disease worldwide. Despite the detailed knowledge on major resistance genes available to date, little is known about how these genes interact with quantitative blast resistance loci and with the genetic background. Knowledge on these interactions is crucial for assessing the usefulness of introgressed resistance loci in breeding germplasm. Our goal was to identify quantitative trait loci (QTL) for blast resistance in rice breeding populations and to describe how they interact among each other and with the genetic background. To that end, resistance to blast was mapped by genome-wide association study (GWAS) in two advanced rice breeding subpopulations, one made of 305 indica type inbred lines, and the other of 245 tropical japonica inbred lines. The interactions and main effects of blast resistance loci were assessed in a multilocus model. Well known, major effect blast resistance gene clusters were detected in both tropical japonica (Pii/Pi3/Pi5) and indica (Piz/Pi2/Pi9) subpopulations with the GWAS scan 1. When these major effect loci were included as fixed cofactors in subsequent GWAS scans 2 and 3, additional QTL and more complex genetic architectures were revealed. The multilocus model for the tropical japonica subpopulation showed that Pii/Pi3/Pi5 had significant interaction with two QTL in chromosome 1 and one QTL in chromosome 8, together explaining 64% of the phenotypic variance. In the indica subpopulation a significant interaction among the QTL in chromosomes 6 and 4 and the genetic background, together with Piz/Pi2/Pi9 and QTL in chromosomes 1, 4 and 7, explained 35% of the phenotypic variance. Our results suggest that epistatic interactions can play a major role modulating the response mediated by major effect blast resistance loci such as Pii/Pi3/Pi5. Furthermore, the additive and epistatic effects of multiple QTL bring additional layers of quantitative resistance with a magnitude comparable to that of major effect loci. These findings highlight the need of genetic background-specific validation of markers for molecular assisted blast resistance breeding and provide insights for developing quantitative resistance to blast disease in rice.

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Mapping of Leaf and Neck Blast Resistance Genes with RFLP, RAPD and Resistance Gene Analogs in Rice

Advances in Rice Blast Research - Developments in Plant Pathology ◽

10.1007/978-94-015-9430-1_4 ◽

2000 ◽

pp. 28-33

Author(s):

K.-L. Zheng ◽

R.-Y. Chai ◽

M.-Z. Jin ◽

J.-L. Wu ◽

Y.-Y. Fan ◽

...

Keyword(s):

Resistance Gene ◽

Resistance Genes ◽

Blast Resistance ◽

Resistance Gene Analogs ◽

Neck Blast ◽

Rflp Rapd ◽

Blast Resistance Genes

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

10.19103/as.2021.0092.23 ◽

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.

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