The Experts below are selected from a list of 12180 Experts worldwide ranked by ideXlab platform
Navreet K. Bhullar - One of the best experts on this subject based on the ideXlab platform.
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Identification of novel alleles of the Rice Blast resistance gene Pi54.
Scientific reports, 2015Co-Authors: Kumar Vasudevan, Wilhelm Gruissem, Navreet K. BhullarAbstract:Rice Blast is one of the most devastating Rice diseases and continuous resistance breeding is required to control the disease. The Rice Blast resistance gene Pi54 initially identified in an Indian cultivar confers broad-spectrum resistance in India. We explored the allelic diversity of the Pi54 gene among 885 Indian Rice genotypes that were found resistant in our screening against field mixture of naturally existing M. oryzae strains as well as against five unique strains. These genotypes are also annotated as Rice Blast resistant in the International Rice Genebank database. Sequence-based allele mining was used to amplify and clone the Pi54 allelic variants. Nine new alleles of Pi54 were identified based on the nucleotide sequence comparison to the Pi54 reference sequence as well as to already known Pi54 alleles. DNA sequence analysis of the newly identified Pi54 alleles revealed several single polymorphic sites, three double deletions and an eight base pair deletion. A SNP-rich region was found between a tyrosine kinase phosphorylation site and the nucleotide binding site (NBS) domain. Together, the newly identified Pi54 alleles expand the allelic series and are candidates for Rice Blast resistance breeding programs.
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Large scale germplasm screening for identification of novel Rice Blast resistance sources.
Frontiers in plant science, 2014Co-Authors: Kumar Vasudevan, Casiana Vera Cruz, Wilhelm Gruissem, Navreet K. BhullarAbstract:Rice is a major cereal crop that contributes significantly to global food security. Biotic stresses, including the Rice Blast fungus, cause severe yield losses that significantly impair Rice production worldwide. The rapid genetic evolution of the fungus often overcomes the resistance conferred by major genes after a few years of intensive agricultural use. Therefore, resistance breeding requires continuous efforts of enriching the reservoir of resistance genes/alleles to effectively tackle the disease. Seed banks represent a rich stock of genetic diversity, however, they are still under-explored for identifying novel genes and/or their functional alleles. We conducted a large-scale screen for new Rice Blast resistance sources in 4246 geographically diverse Rice accessions originating from 13 major Rice-growing countries. The accessions were selected from a total collection of over 120,000 accessions based on their annotated Rice Blast resistance information in the International Rice Genebank. A two-step resistance screening protocol was used involving natural infection in a Rice uniform Blast nursery and subsequent artificial infections with five single Rice Blast isolates. The nursery-resistant accessions showed varied disease responses when infected with single isolates, suggesting the presence of diverse resistance genes/alleles in this accession collection. In addition, 289 accessions showed broad-spectrum resistance against all five single Rice Blast isolates. The selected resistant accessions were genotyped for the presence of the Pi2 resistance gene, thereby identifying potential accessions for isolation of allelic variants of this Blast resistance gene. Together, the accession collection with broad spectrum and isolate specific Blast resistance represent the core material for isolation of previously unknown Blast resistance genes and/or their allelic variants that can be deployed in Rice breeding programs.
Sihai Yang - One of the best experts on this subject based on the ideXlab platform.
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rapid evolution of avirulence genes in Rice Blast fungus magnaporthe oryzae
BMC Genetics, 2014Co-Authors: Ju Huang, Weina Si, Qiming Deng, Ping Li, Sihai YangAbstract:Background Rice Blast fungus Magnaporthe oryzae is one of the most devastating pathogens in Rice. Avirulence genes in this fungus share a gene-for-gene relationship with the resistance genes in its host Rice. Although numerous studies have shown that Rice Blast R-genes are extremely diverse and evolve rapidly in their host populations, little is known about the evolutionary patterns of the Avr-genes in the pathogens.
Li Aihong - One of the best experts on this subject based on the ideXlab platform.
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Strategy for Use of Rice Blast Resistance Genes in Rice Molecular Breeding
Rice Science, 2020Co-Authors: Xiao Ning, Wu Yunyu, Li AihongAbstract:Abstract Rice Blast is one of the most destructive diseases affecting Rice production worldwide. The development and rational use of resistant varieties has been the most effective and economical measure to control Blast. In this review, we summarized the cloning and utilization of Rice Blast resistance genes, such as Pi1, Pi2, Pi9, Pi54, Pigm and Piz-t. We concluded that three main problems in the current breeding of Rice Blast resistance are: availability of few R (resistance) genes that confer resistance to both seedling and panicle Blast, the resistance effect of pyramided lines is not the result of a simple accumulation of resistance spectrum, and only a few R genes have been successfully used for molecular breeding. Therefore, novel utilization strategies for Rice Blast R genes in molecular breeding were proposed, such as accurately understanding the utilization of R genes in main modern Rice varieties, creating a core resistant germplasm with excellent comprehensive traits, screening and utilizing broad- spectrum and durable resistance gene combinations. Lastly, the trends and possible development direction of Blast resistance improvement were also discussed, including new genes regulating resistance identified via GWAS (genome-wide association study) and improving Rice Blast resistance using genetic editing.
Chatchawan Jantasuriyarat - One of the best experts on this subject based on the ideXlab platform.
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Sequence variation of avirulence gene AVR-Pita1 in Rice Blast fungus, Magnaporthe oryzae
Mycological Progress, 2013Co-Authors: Teerapong Kasetsomboon, Sureeporn Kate-ngam, Tanee Sriwongchai, Bo Zhou, Chatchawan JantasuriyaratAbstract:The interaction between Rice, Oryza sativa , and Rice Blast fungus, Magnaporthe oryzae , is triggered by an interaction between the protein products of the host resistant gene, and the pathogen avirulence gene. This interaction follows the ‘gene-for-gene' concept. The resistant gene has effectively protected Rice plants from Rice Blast infection. However, the resistant genes usually break down several years after the release of the resistant Rice varieties because the fungus has evolved to new races. The objective of this study is to investigate the nucleotide sequence variation of the AVR - Pita1 gene that influences the adaption of Rice Blast fungus to overcome the resistant gene, Pi - ta . Thirty Rice Blast fungus isolates were collected in 2005 and 2010 from infected Rice plants in northern and northeastern Thailand. The nucleotide sequences of AVR - Pita1 were amplified and analyzed. Phylogenetic analysis was conducted using the MEGA 5.0 program. The results showed a high level of nucleotide sequence polymorphisms and the positive genetic selection pressure in Thai Rice Blast isolates. The details of sequence variation analysis were described in this article. The information from this study can be used for Rice Blast resistant breeding program in the future.
Kumar Vasudevan - One of the best experts on this subject based on the ideXlab platform.
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Identification of novel alleles of the Rice Blast resistance gene Pi54.
Scientific reports, 2015Co-Authors: Kumar Vasudevan, Wilhelm Gruissem, Navreet K. BhullarAbstract:Rice Blast is one of the most devastating Rice diseases and continuous resistance breeding is required to control the disease. The Rice Blast resistance gene Pi54 initially identified in an Indian cultivar confers broad-spectrum resistance in India. We explored the allelic diversity of the Pi54 gene among 885 Indian Rice genotypes that were found resistant in our screening against field mixture of naturally existing M. oryzae strains as well as against five unique strains. These genotypes are also annotated as Rice Blast resistant in the International Rice Genebank database. Sequence-based allele mining was used to amplify and clone the Pi54 allelic variants. Nine new alleles of Pi54 were identified based on the nucleotide sequence comparison to the Pi54 reference sequence as well as to already known Pi54 alleles. DNA sequence analysis of the newly identified Pi54 alleles revealed several single polymorphic sites, three double deletions and an eight base pair deletion. A SNP-rich region was found between a tyrosine kinase phosphorylation site and the nucleotide binding site (NBS) domain. Together, the newly identified Pi54 alleles expand the allelic series and are candidates for Rice Blast resistance breeding programs.
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Large scale germplasm screening for identification of novel Rice Blast resistance sources.
Frontiers in plant science, 2014Co-Authors: Kumar Vasudevan, Casiana Vera Cruz, Wilhelm Gruissem, Navreet K. BhullarAbstract:Rice is a major cereal crop that contributes significantly to global food security. Biotic stresses, including the Rice Blast fungus, cause severe yield losses that significantly impair Rice production worldwide. The rapid genetic evolution of the fungus often overcomes the resistance conferred by major genes after a few years of intensive agricultural use. Therefore, resistance breeding requires continuous efforts of enriching the reservoir of resistance genes/alleles to effectively tackle the disease. Seed banks represent a rich stock of genetic diversity, however, they are still under-explored for identifying novel genes and/or their functional alleles. We conducted a large-scale screen for new Rice Blast resistance sources in 4246 geographically diverse Rice accessions originating from 13 major Rice-growing countries. The accessions were selected from a total collection of over 120,000 accessions based on their annotated Rice Blast resistance information in the International Rice Genebank. A two-step resistance screening protocol was used involving natural infection in a Rice uniform Blast nursery and subsequent artificial infections with five single Rice Blast isolates. The nursery-resistant accessions showed varied disease responses when infected with single isolates, suggesting the presence of diverse resistance genes/alleles in this accession collection. In addition, 289 accessions showed broad-spectrum resistance against all five single Rice Blast isolates. The selected resistant accessions were genotyped for the presence of the Pi2 resistance gene, thereby identifying potential accessions for isolation of allelic variants of this Blast resistance gene. Together, the accession collection with broad spectrum and isolate specific Blast resistance represent the core material for isolation of previously unknown Blast resistance genes and/or their allelic variants that can be deployed in Rice breeding programs.
