| Brown rot or Bangle blight: Ralstonia solanacearum | 
          
          
            Symptom:
              
                - At the time tuber formation wilt is the main characteristic symptom. 
 
                - In leaf symptom -wilt, stunt and yellowing. Browning of xylem tissue. 
 
                - Eye buds are black in colour. 
 
                - Bacteria ooze coming on infected tuber surface and emits a foul odour.
 
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                Vascular ring | 
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                Oozing out of bacterial exudates | 
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                Rotting of vascular tissue | 
                 
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            Identification of pathogen: 
              Mode of spread and survival: 
              
                - Infected soil and seed tubers form the main source of the primary infection. 
 
                - Brown rot affected plant parts decay and release masses of bacteria in the soil where these may remain viable from season to season. 
 
                - The bacteria in the soil are disseminated by wind from one field to the other. 
 
                - The infection usually occurs through wounds in the root system.
 
               
              Epidemiology: 
              
                - Temp 25to 35ºC , RH above 50 % and PH 6.2-6.6 favours for the development of disease. 
 
                - Acid soil is not favourable.
 
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            Management: 
              
                - Crop rotation of wheat along with potato 
 
                - Use resistant varieties like Solanum pujera
 
                 
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            Source of Images: 
                          http://fera.co.uk/plantClinic/documents/factsheets/brownrot.pdf |