Disease:Bacterial Leaf Streak

Xanthomonas oryzae p.v. oryzicola

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  • Disease 1
  • Disease 2
  • Disease 3
  • Disease 4
  • Disease 5

Symptoms

  • The disease appears as fine watery translucent streaks 0.5 to 5 mm long initially confined to the portion in between the veins.
  • Yellow halo is noticed around the lesions in susceptible varieties.
  • Towards the later phase of the disease, the entire leaves turn yellow in colour which closely resembles the symptoms of bacterial leaf blight. Bacteria exuding from the leaves may dry up to form beads.
  • The symptoms of BLS looks similar to that of narrow brown leaf spot caused by Cercospora, at later stage when the streaks coalese the symptoms resemble that of BLB. However, this can be distinguished by its inner translucent lesions with yellow bacterial ooze.

Procedure for Observation

Ooze test is a simple method to identify the disease.Mark 4 one square meter plots randomly in the field. From each square meter select five hills at random. Conduct ooze test to confirm the incidence and workout the % of plants affected.

2- 5 % Light to moderate

ETL

  • ET L: 2%.

    • Control Measures

  • Use of disease free seeds.
  • Eradication of bacterium by soaking the seeds in Agrimycin 100-250 ppm (2.5g/10kg seed) for 12 h. followed by hot water treatment at 52oC for 30 min. In BLB prone areas treat the seeds with bleaching powder (100g/L)and Zinc sulphate (2%).
  • Destruction of collateral weed hosts.
  • Apply of bleaching powder at the rate of 5kg/ha in the irrigation water to check the spread of BLB especially in the kresek stage.
  • Spraying fresh cow dung extract (20g cow dung is mixed in 1L water and allowed to settle and sieved). The supernatant is taken for spraying @500l/Ha. Spraying antibiotics like Streptocycline 15g/300l/ha. Agrimycin 100 750g/500l/Ha.