Bacterial Blight

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Bacterial Blight

  • Causative Agent: Bacterial blight is primarily caused by Xanthomonas oryzae in rice and Xanthomonas campestris in other crops.
  • Commonly affects rice, but can also impact other crops, such as beans and various vegetables.

Bacterial blight

Transmission:

  • Spread through contaminated water, soil, tools, and infected plant material.
  • Bacteria can survive in plant debris, facilitating disease persistence in fields.

    •   Domain: Bacteria
    •   Phylum: Proteobacteria
    •   Class: Gammaproteobacteria
    •   Order: Xanthomonadales
    •   Family: Xanthomonadaceae
    •   Genus: Xanthomonas
    •   Species: Xanthomonas oryzae (in rice) and Xanthomonas campestris (in other crops)

Within Xanthomonas oryzae, there are two significant pathovars:

  1. Xanthomonas oryzae pv. oryzae: Causes bacterial leaf blight in rice.
  2. Xanthomonas oryzae pv. oryzicola: Causes bacterial leaf streak in rice.

Disease Cycle:

  • The bacteria can survive in infected plant debris and are spread through water, wind, and contaminated tools.
  • The disease often thrives in warm, humid conditions.

Symptoms:

  • Leaf Discoloration: Initial symptoms include water-soaked lesions on leaves, which can develop into yellow or brown streaks.
  • Wilting: Affected plants may exhibit wilting, especially during hot weather.
  • Necrosis: In severe cases, leaf tissues die, leading to a blighted appearance.

Management Strategies:

  1. Cultural Control:
    • Practice crop rotation and avoid planting susceptible crops in the same area.
    • Ensure good drainage to minimize water pooling.
  2. Resistant Varieties:
    • Use resistant or tolerant plant varieties when available.
  3. Sanitation:
    • Remove infected plant debris and disinfect tools to prevent spread.
  4. Chemical Control:
    • Apply bactericides as a preventive measure, especially during high-risk periods.

 

 

 

  

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