Leaf mite infestation in rice – Methods to Control

Rice leaf mite has attained a pest status in the Cauvery deltaic regions of Tamil Nadu. Infestation starts early from the nursery till stem elongation stage.

Leaf mites feed on upper and lower surface of rice leaves. Usually they are more numerous on lower surface than upper surface.

Leaf mites are small and microscopic spider mites which pierce the leaf tissue and suck the exuding sap.

They multiply very fast under congenial conditions and damage the entire leaf portion under severe infestation.

Damage results in the appearance of yellowish brown specks which increase under severe conditions and whole leaf turns to greyish white and dries up.

Usually the initial symptoms of damage are from the periphery of the rice field and later depending upon wind speed directions the intensity of leaf area loss is manifested.

Most severe

The damage is most serious during the high temperature time with high relative humility (June – July). Entire life cycle can take 8-12 days.

Adults are sexually mature when they emerge and mate as soon as possible. Egg laying begins in 1-3 days, and singly in rows along the leaf midribs and veins. Incubation lasts 4-9 days.

This is followed by the three immature stages – larva, protonymph and deutonymph.

The mite is active and breeds throughout the year building large population during hot weather when the life cycle takes the shortest time.

Management methods

Use of chisel ploughing once in four years.

Create a rice free period by ploughing down stubbles between crops or follow rice fallow crops with pulses/green manures maize in endemic areas.

Maintaining the bunds free from weeds. Seed treatment with Pseudomonas at 10 grams/ 1kg of seeds.

Topdressing of urea with neem cake (5:1) with LCC (Leaf Colour Chart) based N and to avoid excess Nitrogen application.

Top dressing of 50 per cent potash fertilizer. Spraying of Profenophos 50 EC 1000 ml/ ha along with khadi bar soap 1.5 kg controls leaf mite.

Tamil Nadu Rice Research
Institute, TNAU
Aduthurai, Tamil Nadu