Etiology deals with cause of disease

1. PHASES OF PLANT PATHOLOGY STUDY
https://www.youtube.com/watch?v=-881nYz1eLY&t=9s

2. Etiology: Study of cause of disease
Disease Plant/Part
Abiotic Factor Biotic Factor
 Temperature Fungi
 Water Bacteria
 Nutrients Virus
 Wind Nematode
 How we can come to conclusion? Sometime its very easy

4. Most of times it is bit tricky?
 You need to cut disease portion and place to media? If it is hemi-biotroph or necrotroph then it grow
but if biotroph like most of viruses & rust fungi then it will not grow on media.
 Therefore, we adopt a different strategy to be sure that disease is caused by a biotroph
I. By inoculating healthy plant with sap of disease plant or spore of fungi
II. ELISA
III. PCR

5. It not ends by knowing nature of pathogen but open plethora more questions?
Suppose if it is fungi THEN
 Lower or Higher Fungi?
 If Higher then Asco or Basidiomycete?
 What is family, order, genus, species etc. ?

6. Why every pathology study whether in plants or human or animals starts
with “Cause”?
Effective management depends upon effective diagnostics
Etiology is foundation stone on which whole building of plant pathology
study is built?