Fall armyworm may attack maize : Experts

Tribune News Service

Ludhiana, January 22

Punjab Agricultural University (PAU), Ludhiana, has cautioned farmers against attack of fall armyworm on maize crop.

Fall armyworm was reported in Punjab towards the end of Kharif 2019. The pest had widespread occurrence and may reappear in spring maize. It may also migrate from neighbouring states.

Dr JS Chawla, In-charge, Maize Section, PAU, aksed farmers to stay alert to avoid population build up and severe damage. Farmers should survey their fields thoroughly, he said.

Dr Harpreet Kaur Cheema, Entomologist (Forage), said, “Larval stage of fall armyworm damages crop. The larva can be easily identified by presence of four spots arranged in a square pattern at the tail end and a predominant white coloured inverted Y-shaped mark on the head. The younger larvae feed by scrapping the leaf surface and making papery windows. The bigger larvae damage central whorl leaves voraciously, causing round to oblong holes and producing a large amount of faecal matter.”

Since maize is grown almost round the year, management of this new invasive pest should be done at first appearance to minimise its impact, he said.

“Avoid very early and late sowing of spring maize, sow only from February 1 to 15. Fodder maize sowing should be restricted from April 15 to August 15 to limit multiplication of the pest. Strictly avoid staggered sowing of maize, especially in the adjacent fields,” said Dr Chawla.

The severity of the pest increases in higher plant density in case of fodder crop. Therefore, don’t use more seed than recommended (30 kg/ acre), he said, while suggesting line sowing (row spacing 30 cm), rather than broadcasting. Prefer mixed cropping of fodder maize with cowpea/ bajra/ sorghum over sole crop, he added.

Dr Jawala Jindal, Senior Entomologist (Maize), said, “As soon as attack of fall armyworm is noticed, to control smaller larvae, spray Bacillus thuringiensis var. kurstaki (BtK) based formulations at 2ml/ litre of water. If the incidence of fall armyworm is higher than 5 per cent on plant basis and the larvae are bigger, spray the grain maize crop with Coragen 18.5 SC (chlorantraniliprole) at 0.4 ml/ litre or Delegate 11.7 SC (spinetoram) at 0.5 ml/ litre or Missile 5 SG (emamectin benzoate) at 0.4 gm /litre. In fodder maize, spray of Bacillus thuringiensis var. kurstaki (BtK) based formulations @ 2ml/ litre of water or Coragen 18.5 SC (chlorantraniliprole) @ 0.4 ml/ litre can be done, but not beyond 40 days of sowing to maintain a waiting period of at least 21 days before harvest. For effective control, direct the spray nozzle towards the whorl. The amount of water to be used should be 120 litres up to 20 days old crop and 200 litres for older crop ( > 20 days).”