EU Compliant Paddy (Step 7)

Pest Management

Major insects

1. Rice stem borer:

Identification Recommendations:

  • The earhead becomes white, straight, and empty.
  • Holes are observed in the lower stem of the plant.
  • Spray immediately when the ETL is crossed.

Symptoms:

  • The larvae of these insects bore into the stem and cause damage from July to October. The affected young plants show dead-hearts (yellowing and drying of central shoot) whereas the old ones produce empty earheads which turn white and stand erect.
    ETL: 5% Dead heart / 5% White ear.
Fig: Stem borer in Rice

Management:

  • The fields showing more than 5% dead hearts (Economic Threshold Level, ETL) should be broadcasted with Thiamethoxam 1% + Chlorantraniliprole 0.5% GR @ 2500gms per acre at 25 days after transplanting. Foliar spray of Isocycloseram 18.1% w/w SC @ 120 ml per acre or Chlorantraniliprole 9.3% + Lambda-cyhalothrin 4.6% ZC @ 100 ml per acre at 35-40 days after transplanting. Spray Chlorantraniliprole 9.3% + Lambda-cyhalothrin 4.6% ZC @ 100 ml per acre at 60-65 days after transplanting. Further application of any of these insecticides may be repeated as and when damage reaches economic threshold level. Prefer neem-based bio-pesticide at pest initiation stage.
  • Avoid taking ratoon crops.

Biological management:

  • Release of Egg parasitoid Trichogramma chilonis and Trichogramma japonicum @ 1 lakh/ha on occurrence of rice stem borer.
  • Natural enemies such as Apanteles, Bracon, Platygaster, coccinellids, Telenomus, spiders, Trichogramma, etc should be conserved in fields.
  • Placing of bird perches for predatory birds.
  • Collection of egg masses of rice stem borer and putting them in a bamboo cage and kill the hatching larvae.
  • Installation of pheromone traps @10 traps/acre for mass trapping of rice stem borer.
  • Release of Larval parasitoid Amauromorpha accepta, Cotesia flavipes, Bracon sp which feed on stem borer larvae.

2. Leaf folder:

Identification Recommendations:

  • Leaves curl at the edges and form tubes.
  • Green larvae are visible inside the curled leaves.
  • The chlorophyll of the leaves is lost and white/dry streaks appear.
  • The leaves appear scorched and dry.
  • Control/spray immediately if the ETL is exceeded.

Symptoms:

  • The larvae fold the leaves, eat out the green tissue and produce white streaks. The damage is highest during August-October. Adopt control measure when the leaf damage reaches 10% (ETL).

Mechanical Management:

  • The mechanical control of leaf folder can be done only before flowering by passing the 20-30 m long coir/jute rope, forwards and then backwards, both ways while touching the crop canopy. While passing the rope, ensure that water must be standing in the crop.

Chemical Management:

  • Broadcast Thiamethoxam 1% + Chlorantraniliprole 0.5% GR @ 2500gms per acre at 25 days after transplanting. Foliar spray of Isocycloseram 18.1% w/w SC @ 120 ml per acre or Chlorantraniliprole 9.3% + Lambda-cyhalothrin 4.6% ZC @ 100 ml per acre at 35-40 days after transplanting. Spray Chlorantraniliprole 9.3% + Lambda-cyhalothrin 4.6% ZC @ 100 ml per acre at 60-65 days after transplanting. neem-based bio-pesticide, azadirachtin 5% in 100 litres of water per acre. Prefer Neem based bio-pesticide at pest initiation stage.

Biological management:

  • Release of Egg parasitoid Trichogramma chilonis and Copidosomopsis nacoleiae @ 1 lakh/ha on occurrence of leaf folder.
  • Release of larval parasitoid Stenobracon nicevillei, Elasmus sp which feed on leaf folder larvae.
  • Natural enemies such as Carabid beetle, Spiders will prey on leaf folder.

3. Brown planthoppers:

Identification Recommendation:

  • Small brown/white insects are seen in clusters on the lower parts of the plant (stem/leaf sheath)
  • Nymphs and adults suck plant sap, causing leaves to turn yellow and dry
  • Plants dry in circular or patch-like areas in the field (hopper burn)
  • On slight disturbance, insects jump or fly quickly
  • Due to honeydew secretion, black sooty mold may develop
  • Take immediate control/spraying measures when ETL (Economic Threshold Level) is crossed.

Symptoms:

  • These hoppers include, white backed plant hopper and brown plant hopper.
  • Both nymphs and adults of these pests suck the cell sap particularly from the leaf-sheath from July to October. The crop dries up in patches a condition known as Hopper burnt. As the plants dry up, the hoppers migrate to the adjoining plants and kill them. In a few days, the area of the dry patches enlarges.
    ETL: First spray should be done when dead heart reaches 5% and at the booting stage (55–60 DAT).

Management:

  • About one month after transplanting, a few plants in the field should be slightly tilted and tapped 2 or 3 times at the base at weekly interval. When minimum 5 planthoppers per hill (ETL) are seen floating in the water. Foliar spray of Pymetrozine 50% WDG @ 120 ml per acre at 60-65 days after transplanting followed by 2nd spray at 80-85 days after transplanting. Repeat the spray if necessary. For better effectiveness, use knapsack sprayer while directing its spray towards the base of the plants. If the damage is noticed at hopper burn stage, treat the affected spots along with their 3-4 m periphery immediately as these spots harbor high population of the insect.

Biological management:

  • Release of egg parasitoid Gonatocerus spp, Anagrus spp, Oligosita spp, to reduce hoppers population.
  • Releasing of larval parasitoid Haplogonatopus sp and Pseudogonatopus spp to feed on growing larvae.
  • Natural enemies such as Coccinellid beetles, Carabid beetle, Rove beetle, will reduce the pest in paddy.
  • Pest defender ratio (P: D) 2:1 may be helpful in avoiding the application of pesticides against plant hoppers.

4. Rice hispa:

Symptoms:

  • Rice hispa is a serious pest. The grubs of this pest tunnel into the leaves, whereas the adults are exposed feeders. The grubs cause damage by producing bold, white streaks on the leaves.

Management:

  • If the attack starts in nursery, clip-off and destroy the leaf tips of the affected seedlings before transplanting. On the transplanted crop, spray 600 ml of quinalphos or Lambda Cyhalothrin 5% SC @ 100ml per acre with a manually operated sprayer. Repeat the spraying if the attack persists.

Biological management:

  • Larval parasitoid Bracon sp. Is used against for the reduction of Rice hispa.

5. Gundhi bug:

Symptoms:

  • Black spots appear on the grains and it can lead to the formation of chaffy grains.
  • It usually attacks during the milky stage of rice crop.
  • During evenings, foul smell is emitted from the rice fields infested with gundhi bug.

Management:

  • Foliar spray of Deltamethrin 11% w/w SC @ 60 -75 ml per acre at 70 days after transplanting.
    Spraying should be done during the evening hours from borders towards centre of the field.

Biological Methods:

  • Among the biological control agents, small wasps parasitize the eggs and the meadow grasshoppers’ prey on them.
  • Both the adults and nymphs are preys to spiders, coccinellid beetles and dragonflies.
  • A fungus infects both nymphs and adults.

6. Termites:

Symptoms:

  • Plants affected with termites shows yellowing and wilting which leads to death.
  • Affected plants can be easily pulled out by hand. The germinating seeds attacked by termites fail to germinate that can reduce plant stand and resowing is required in case of severe infestation.
  • At night, the termites move to the ground and randomly cut the seedlings at ground level and cover them with soil to eat later.
Previous
Next