Citrus Canker PPT (Symptoms, Causal Organism, Etiology and Control Measures)
Citrus Canker: Symptoms of Citrus Canker, What is the Symptoms and Causal Organism of Citrus Canker Disease, Disease Cycle (Etiology) and Control Measures of Citrus Canker, Economic Loss due to Citrus Canker, Xanthomonas citri.
Blast Disease of Paddy PPT (Symptoms, Causal Organism, Etiology and Control Measures)
Blast Disease of Paddy: Symptoms of Paddy Blast, What is the Causal Organism of Paddy Blast Disease, What is the Causal Organism of Blast of Paddy, Disease Cycle (Etiology) and Control Measures of Blast Disease of Paddy.
Cassava Mosaic Disease PPT (Symptoms, Causal Organism, Etiology and Control Measures)
Cassava Mosaic Disease, Tapioca Mosaic Disease, Tapioca Mosaic Virus, Causal Organism of Tapioca Mosaic Disease, How to Control Cassava Mosaic Disease? What are the symptoms of Tapioca Mosaic Disease, Structure of Tapioca Cassava Mosaic Virus.
Toxins in Plant Pathogenesis Toxins in Plant Pathogen Interaction
The process of pathogenesis (the onset of diseased condition) in plants is facilitated by many factors such as virulence of the pathogen, susceptibility of the host, presence of suitable environmental conditions and various enzymes and metabolites of pathogens. Previously we have discussed the importance of different enzymes involved in plant pathogen interactions. These enzymes facilitate the entry of the pathogen into the host and help to colonize inside the host cell. The production of different hydrolytic enzymes may not always result in the establishment of pathogen inside the host tissue. Certain plant pathogen may successfully invade the host tissue area but fail to induce the onset of disease. These findings highlighted the involvement of certain toxins, microbial toxins or aggressins, in the establishment of diseased conditions in plants. The present post describes the Toxins involved in plant pathogen interaction and pathogenesis with examples.
What is meant by ‘toxin’ in Plant Pathology?
ØDefinition: Any substances produced by a pathogen which is injurious to host and it directly and immediately play a crucial role in pathogenesis.
Ø Toxins involved in plant parasite interactions are also called as aggressin.
Ø According to Koch’s postulates, a substance to be called as a ‘toxin’ should follow the following criterions:
@. The compound must be isolated from the diseased plant
@. It should NOT be present in the healthy plant
@. Compound must be chemically characterized
@. When isolated toxin is reintroduced to a healthy host, it should produce the original symptoms.