Bacterial Leaf Streak

  • Symptoms

  • Trigger

  • Biological Control

  • Chemical Control

  • Preventive Measures

Bacterial Leaf Streak

Xanthomonas oryzae pv. oryzicola

Bacteria


In a Nutshell

  • Dark green, later brown to yellowish-grey, linear lesions on leaves.
  • Entire leaves can turn brown.

Hosts

Rice

Symptoms

At an initial stage of the infection, the leaves show dark-greenish streaks with water-soaked spots on infected leaves. These lesions increase in number and become yellowish-orange to brown. Lesions may show amber-colored droplets of bacterial exudate. Later, the observable symptoms of infection with Bacterial Leaf Streak are very similar to Leaf Blight, but the lesions caused by Bacterial Leaf Streak are more linear and the edges are not as wavy as the margins of leaves infected with Leaf Blight.

Trigger

The bacteria spread with irrigation water and the infection is linked to rain, high humidity and high temperature. The disease does not develop in cool and dry conditions. The bacteria enter the leaf through the stomata and wounds and multiply inside. Depending on moist conditions during the night, bacterial exudate forms on the leaf surface.

Biological Control

Sorry, we don't know of any alternative treatment against Xanthomonas oryzae pv. oryzicola. Please get in touch with us in case you know of something that might help to fight this disease. Looking forward hearing from you.

Chemical Control

Always consider an integrated approach with preventive measures and biological treatments if available. In case of severe infections, apply copper-based fungicides at heading to control effectively the disease. Copper fungicides should not be used during earlier stages, only from late flowering stage.

Preventive Measures

Plant healthy, resistant seedlings.,Keep fields clean and remove weed hosts.,Plow under rice stubble, straw, rice ratoons, and volunteer seedlings.,Ensure optimal application of nutrients, especially nitrogen.,Optimize drainage of fields and nurseries.,Dry the field during the fallow period to kill bacteria in soil and residues.,Drain the field during severe flood.,Sow seeds in colder periods so the pathogen cannot grow.