Management of Fall Army Worm in Sorghum

Crop stage : Crop stage: Before sowing

Intervention : Precautionary measures to be followed before planting of the crop

IPM measures

• Deep ploughing to expose pupae to sun light and predatory birds
• Maintain clean field bunds and plant flowering crop plants, viz.. Tagetes spp. Cosmos spp. etc. to attract the natural enemies.
• Planting Napier grass/hybrid Napier in border and intercropping sorghum with pigeon pea, cow pea in 2:1 to 4:1 ratio is advisable.

Crop stage : Sowing and post sowing cultural and mechanical practices

Intervention : Better sowing method, pheromone installation, clean cultivation and mechanical measures

IPM measures

• Follow ridge and furrow planting method instead of flat sowing Erect bird perches (@25/ha to encourage insectivorous bird soon after emergence.
• Nutritional management: Apply recommended dose of NPK. Balanced application of fertilizers helps to reduce the incidence of FAW
• Clean cultivation by removing weeds which serve as alternate host of FAW.
• Treat the seed with Cyantraniliprole 19.8% + Thiamethoxam 19.8% FS @ 6 ml /kg seed for protection during seedling stage

Crop stage : Seedling stage (0 to 30 days old crop)

Intervention : Application of neem based pesticide, bio pesticides and bioagents; minimize use of chemical pesticides.

IPM measures

• Most vulnerable stage, very crucial period for management. Spray neem formulation (Azadiractin. 1500 ppm) @ 5 ml/I or one lit/acre or 5 % Neem seed kernal estract (NSKE) immediately after observation of one moth/trap/day or 10 % plant infestation at papery windows Stage.
• Hand collection and destruction of larvae and egg in patchy incidence
• Erection of pheromone traps @15/ac for mass trapping of adults (effectiveness of lure last for 30-45 days)
• Release of Telenomus remus (4000/ac) or Trichogramma pretiosum @ 50,000/ac at 7 and 14 days after planting. Parasitoid release may be alternated with neem spray at weekly intervals, but not together.
• For management of early instars, whorl application of Bacillus thuringiensis v kurstaki formulations 2% @ 2g/l or Metarhizium anisopliae or Beauveria bussiana @ 5 g /liter is recommended.
• If incidence is more than 10%, any of the recommended synthetic pesticides. viz. Spinetoram 11.7% SC @ 0.5 ml/l or Chlorantraniliprole 18.5 SC @0.4 ml/l or Thiamethoxam 12.6 % + Lambada Cyhalothrin 9.5 % ZC @0.25 ml/I is recommended.

Crop stage : Early whorl stage (30-50 days)

Intervention : Application of neem based pesticide, bio pesticides and bioagents; minimize use of chemical pesticides.

IPM measures

• Very crucial period for management. Spray neem formulation (Azadiractin, 1500 ppm) @ 5 ml/I or one lit/acre or 5% Neem seed kernal extract (NSKE) immediately after observation of one moth/ trap/ day or 10 % plant infestation at early whorl stage.
• Spray (Whorl application) Bacillus thuringiensis v. kurstaki formulations 2% @2g/l or Metarhizium anisopliae or Beauveria bassiana @ 5 g/ liter at 5-10% infestation. Repeat the spray based on weekly scouting at >10% fresh infestation.
• If incidence is 10 -20 % any of the recommended synthetic pesticides, viz., Spinetoram 11.7 % SC @ 0.5 ml/l or Chlorantraniliprole 18.5 SC @ 0.4 ml/l or Thiamethoxam 12.6 % + Lambda cyhalothrin 9.5 % ZC @ 0.25 mI/l is recommended.

Crop stage : Late whorl to boot stage window (50-70 day old crop)

Intervention : No chemical intervention

IPM measures

• Timely management measures at seedling and early whorl stage reduces FAW damage to greater extent.
• If incidence is more than 20%, any of the recommended synthetic pesticides, viz. Spinetoram 11.7% SC @ 0.5 ml/l or Chlorantraniliprole 18.5 SC @ 0.4 ml/l or Thiamethoxam12.6 % + Lambda cyhalothrin 9.5% ZC@ 0.25 ml / l is recommended.

Precautions for pesticide use

• Insecticide sprays should be rotated with another recommended chemical in subsequent sprays to avoid build up of resistance in FAW to insecticides.
• Enter the field only 48 hours after spraying the pesticide.
• Harvesting should be done 30 days after last spray of pesticide and the left over fodder may be fed to animals.

Source : Directorate of Plant Protection, Quarantine and Storage