Root Knot Disease and Its Control
The rice rot knot disease is caused by the nematode (Meloidogyne spp) that attack on rice roots.
-
This disease occurs in all rice growing areas on the world.
-
Formation of hooked-shaped galls on the roots of the infected plants.
-
If infection starts soon after planting rice, severe disease symptoms will be observed.
Symptom
-
Formation of galls or knots on roots of the infected rice plants.
-
Symptoms on ground can be observed as yellow leaves, stunt plant growth, poor tillering, emergence of unfilled spike-lets on panicles.
 |
 |
|
Hook-shaped galls on roots (source: IFAS) |
Root knot disease affected rice field (Source: TNAU Agritech portal) |
Disease Cycle
-
The infectious nematodes grow and multiply in soils and in the rice roots, then spread disease from old season to new season through the root’s residues and the soils.
Good Practices for Control
-
Crop rotation practice with crops such as sesame, sunflower, jute and cowpea and apply potash fertilizer, rice husk ash, neem cake and other natural fertilizers.
Chemical Control
-
Use the recommended nematicides.
-
Soaking the rice seedling with Carbosulfan 0.1% can reduce the growth and multiplication of nematodes.
-
Most effective prevantion is to fumigate into the soils by using Metham potassium or Metham sodium or 1, 3 dichloropropene (1, 3-D 97).