Related Experiment Video
Updated: Jan 28, 2026
06:34
Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS
Published on: July 11, 2016
20.0K
Identification of Resistance Genes Effective Against Rice Bacterial Blight Pathogen in Eastern India.
Marella Lalitha Shanti1, M L C George2, C M Vera Cruz2
1Central Rice Research Institute (CRRI), Cuttack 753 006, India.
Plant Disease
|March 3, 2019
Summary
Understanding rice bacterial blight pathogen populations in India is crucial for breeding resistance. Gene pyramiding, like Xa4 + xa5 + Xa21, offers broad-spectrum resistance against diverse Xanthomonas oryzae pv. oryzae strains.
Area of Science:
- Plant Pathology
- Genetics
- Agricultural Science
Background:
- Bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is a major rice disease globally.
- Effective breeding for resistance requires knowledge of local pathogen populations and their virulence.
- Deployment of resistance genes necessitates understanding pathogen diversity in target regions.
Purpose of the Study:
- To characterize the genetic diversity and virulence of Xanthomonas oryzae pv. oryzae populations in India.
- To evaluate the efficacy of known bacterial blight resistance genes and their combinations against diverse pathogen strains.
- To provide insights for developing durable resistance strategies in rice.
Main Methods:
- Collection and characterization of 450 Xanthomonas oryzae pv. oryzae strains from three Indian states.
- Polymerase chain reaction (PCR) fingerprinting for haplotype analysis.
- Virulence assays on near-isogenic rice lines carrying specific resistance genes (Xa3, Xa4, xa5, Xa7, Xa10, xa13, Xa21) and gene pyramids.
Main Results:
- Seventeen distinct haplotypes and nine pathotypes were identified among the Indian Xoo strains.
- Significant regional variations in haplotype distribution were observed, with the Orissa population showing the highest diversity.
- Pathogen strains virulent to individual resistance genes were prevalent, but no single strain defeated all tested resistance genes.
- Gene combinations Xa4 + xa5, xa5 + Xa21, and Xa4 + xa5 + Xa21 demonstrated broad-spectrum resistance against all evaluated strains.
Conclusions:
- The study highlights significant genetic diversity in Indian Xanthomonas oryzae pv. oryzae populations.
- Pyramiding of specific resistance genes (e.g., Xa4 + xa5 + Xa21) is a viable strategy for achieving broad-spectrum and durable bacterial blight resistance in rice.
- Understanding regional pathogen populations is essential for successful deployment of resistance genes.
More Related Videos
08:17VIGS-Mediated Forward Genetics Screening for Identification of Genes Involved in Nonhost Resistance
Published on: August 23, 2013
17.6K
08:58Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
7.8K
Related Concept Videos
01:31Defense Against Bacterial Pathogens
2.8K
The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
2.8K
02:39Gene Flow
37.7K
Gene flow is the transfer of genes among populations, resulting from either the dispersal of gametes or from the migration of individuals.
37.7K
01:33Bacterial Transformation
59.7K
In 1928, bacteriologist Frederick Griffith worked on a vaccine for pneumonia, which is caused by Streptococcus pneumoniae bacteria. Griffith studied two pneumonia strains in mice: one pathogenic and one non-pathogenic. Only the pathogenic strain killed host mice.
Griffith made an unexpected discovery when he killed the pathogenic strain and mixed its remains with the live, non-pathogenic strain. Not only did the mixture kill host mice, but it also contained living pathogenic bacteria that...
Griffith made an unexpected discovery when he killed the pathogenic strain and mixed its remains with the live, non-pathogenic strain. Not only did the mixture kill host mice, but it also contained living pathogenic bacteria that...
59.7K
01:30Bacterial Signaling
40.6K
Bacterial signaling can occur within bacteria (intracellular) or between bacteria (intercellular). At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that causes changes in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell...
40.6K
02:19Buffer Effectiveness
55.1K
Buffer solutions do not have an unlimited capacity to keep the pH relatively constant . Instead, the ability of a buffer solution to resist changes in pH relies on the presence of appreciable amounts of its conjugate weak acid-base pair. When enough strong acid or base is added to substantially lower the concentration of either member of the buffer pair, the buffering action within the solution is compromised.
The buffer capacity is the amount of acid or base that can be added to a given volume...
The buffer capacity is the amount of acid or base that can be added to a given volume...
55.1K
01:22Resistivity
4.5K
When a voltage is applied to a conductor, an electrical field is generated, and charges in the conductor feel the force due to the electrical field. The current density that results depends on the electrical field and the properties of the material. In some materials, including metals at a given temperature, the current density is approximately proportional to the electrical field. In these cases, the current density can be modeled as:
4.5K