According to a statement by CropLife SA, farmers affected by FAW should spray insecticides as soon as the pest is noticed, or if 5% to 10% of plants show infestation (five to 10 plants per 100 plants inspected).
Only products containing the active ingredients already approved for fall armyworm by the registrar of the Fertilizers, Farm Feeds, Agricultural Remedies and Stock Remedies Act No. 36 of 1947 should be used.
According to the latest CropLife SA protocols, insecticides must be applied during the early development stages of larvae. Adult larvae may prove to be very difficult, if not impossible to control.
The best time for application is when larvae feed on exposed leaf surfaces where insecticides can reach them outside cobs, ears and tassels. As soon as larvae penetrate too deeply into the whorl or feed inside the cob, it becomes virtually impossible to effectively control the pest.
In addition, smaller larvae are easier to control than fully-grown larvae.
Dr Gerhard Verdoorn, director of CropLife SA, said insecticides should be applied strictly according to the recommendations on the label. Control varies from very poor to adequate with the use of carbamates and organophosphates.
It is, however, advisable to test any carbamates and organophosphates on a small patch for efficacy before using it on a large scale. Certain strains of Bacillus thuringiensis may not be effective against FAW and it is therefore vital to test products before using it extensively, he said.
In the statement, CropLife SA advised producers to calibrate sprayers and ensure that sprayers and nozzles were in good working condition, and delivered the correct droplet size and spray volume.
Nozzles need to be aimed at plant rows and not between rows to ensure that the target is reached with the maximum spray volume. Optimal spray volumes are recommended. On average, between 200 and 400 litres/ha for maize crops should be adequate to deposit active ingredients on the target.
Water pH and adjuvants also have to be adjusted according with the recommendations on the label, the statement said. – Annelie Coleman
Insecticides that can be used to control FAW
|Active ingredient(s)||Trade name||Reg Nr.||Status||Reg Holder|
|Indoxacarb||Steward 150 EC||L8453||Registered||DuPont de Nemours|
|Indoxacarb||Advance 150 SC||L9147||Registered||Universal Crop Protection|
|Indoxacarb||Addition 150 SC||L9146||Registered||Villa Crop Protection|
|Indoxacarb||Doxstar Flo||L9884||Registered||Meridian Agrochem. Company|
|Chlorantraniliprole||Coragen||L8592||Registered||DuPont de Nemours|
|Emamectin benzoate||Emma||L9022||Registered||Arysta LifeScience|
|Emamectin benzoate||Vitex 50||L9525||Applied for||Meridian Agrochem, Company|
|Emamectin benzoate||Promex 20 EW||L9729||Applied for||Meridian Agrochem. Company|
|Emamectin benzoate||Warlock 19.2 EC||L9872||Applied for||Amada South Africa|
|Methomyl||FarmAg Methomyl 900||L3430||Applied for||Castle Ag-Chem|
|Methomyl||Mylomex 200 SL||L4367||Applied for||Nulandis|
|Profenophos||FarmAg Profenofos 500||L5547||Applied for||Castle Ag-Chem|
|Lufenuron||Lepidex||L7977||Applied for||Meridian Agrochem. Company|
|Spinetoram||Delegate 250 WG||L8239||Applied for||Dow AgroSciences|
|Spinetoram/Methoxyfenozide||Uphold 360 SC||L10164||Applied for||Dow AgroSciences|
|Benfuracarb/Fenvalerate||Oncol Super 220 SC||L7649||Applied for||Dow AgroSciences|
|Chlorpyrifos||Avi Klorpirifos 480 EC||L4318||Registered||Avima|
|Mercaptothion||Avi Merkaptotion DP||L5966||Applied for||Avima|
|Mercaptothion||Avi Gard||L0216||Applied for||Avima|
|Azadirachtin||Neemazal||L7840||Applied for||Klub M5|
|Bacillus thuringiensis var azawai||Florbac WG||L5531||Applied for||Philagro|
|Novaluron/Indoxacarb||Plemax||L10246||Registered||Adama South Africa|