Ufra Nematode and Its Control

• Rice Ufra disease is caused by the rice stem nematode (Ditylenchus angustus).

• In the Mekong countries, this disease causes severe damages in deep-water rice fields.

• The disease occurrence normally starts at early growth stage before tillering. 

• If the infection attack on newly transplanted young plants, it can affect on yield about 30-80% reduction and even up to 100% loss.

•  The whole paddy field turn dried like fire burnt, if the disease infection is severe.

Symptoms

• Many white spots spread at the base of the leaves in the young plant stage before tillering and the spots turn brown. White splash at the lower part of growing leaves.

•  Irregular leaf sheaths, malformation and curled leaves formation can be observed.

• The internodes at the top of the stem turn dark-brown and causes irregular tillering from the nodes at the base of the plant.

• Infected plants produce twisted panicles, small and unfilled panicles or remain partially or completely enclosed within the leaf sheaths in severe cases.

 

 

Disease Cycle

• Disease infection can occur from irrigation and drainage practices. 

• Nursery preparation on disease infected plot in previous year, will remit disease to new rice fields through the seedlings.

• Disease infected plant parts from last year, residue in the plot will transfer disease. 

 

Chemical Control

 

• Spray with pesticides such as Carbendazim 3ml/Lit (0.3%) in the nursery and the field when emergence of disease infection.

• Spray 0.2% Diazinon (60 e.c.) or 0.1% Benomyl (50 w.p.) or 3% Carbofuran granules 22.kg/ha , three times with 15 days interval.