The following points highlight the three main stages of host pathogen relationship. The stages are: 1. Pre-Penetration Stage 2. Penetration Stage 3. Post-Penetration Stage. 1. Pre-Penetration Stage: During pre-penetration stage the pathogen (inoculum) on arrival on the host surface interacts sharply with the surrounding environment and host itself. The enÂvironment which is an aggregate of all external conditions including temperature, [...]
In this article we will discuss about the classification of plant diseases. (i) Diseases classified in relation to their occurrence: Study of plant disÂeases in relation to their occurrence (interaction of populations of plants, pathogens and environment) is known as epidemiology. There may be infectious disease and contagious disease. A disease which spreads slowly and is incited by a transmissible [...]
The following points highlight the top sixteen mechanisms of dissemination of plant diseases. Some of the mechanisms are: 1. Dissemination by Seed 2. Dissemination by Propagating Stock 3. Dissemination with Plant Debris 4. Dissemination with Manure 5. Dissemination with Soil 6. Dissemination by Field Operations and Implements 7. Dissemination by Insects 8. Dissemination by Animals Other Than Insects and Others. [...]