Canola, Forage brassica – Diamondback moth, cabbage moth

Crop(s) Canola, forage brassica
Insect(s) Diamondback moth, Cabbage moth (Plutella xylostella)

Guidelines 

For information, refer to the IPM guidelines: https://ipmguidelinesforgrains.com.au/ipm- information/resistance-management-strategies/. 

Notes regarding the application of insecticide 

  1. To ensure the most effective control of the pest: 
  2. Product labels should at all times be carefully read and adhered to; 
  3. Full recommended rates of registered insecticides should always be used; and 
  4. Ensure good coverage of the target area to maximise contact. 

 

To help prevent the development of resistance to any one specific active ingredient (see table below), observe the following instructions: 

  1. Apply a specific active ingredient using a ‘window’ approach to avoid exposure of consecutive insect pest generations to the same mode of action. Multiple successive applications of a specific active ingredient are acceptable if they are used to treat a single pest generation. 
  2. Following a ‘window’ of a specific mode of action product, rotate to a ‘window’ of applications of effective insecticides with a different mode of action. 
  3. The total exposure period of any one mode of action ‘active window’ applied throughout the crop cycle (from seedling to harvest) should not exceed 50% of the crop cycle. 
  4. Incorporate IPM techniques into the overall pest management program. 
  5. Consider the impact on beneficial insects. Consult the Cesar Australia Beneficials Chemical Toxicity table:  https://cesaraustralia.com/resources/beneficials-toxicity-table/. 
  6. Monitor insect populations for loss of field efficacy. 

 

MoA Group*  Chemical subgroup  Active ingredient  No. applications permitted per crop per season  Crops 
1A  Carbamates  methomyl (eg. Lannate® L), thiodicarb (eg. Larvin®)  not specified  Canola, rapeseed, brassicas 
3A  Pyrethroids  synthetic pyrethroids (various – eg. Dominex® Duo, #Karate® Zeon, *Sumi-alpha® Flex, #Trojan®)  not specified  Canola, #forage brassicas, *fodder rape, *chou moellier 
5  Spinosyns  spinetoram (Success® Neo)  2  Canola, forage brassicas 
6  Avermectins  emamectin benzoate (eg. Affirm®)  2  Canola 
11A  Bacillus thuringiensis  Bacillus thuringiensis (eg. Dipel®)  not specified  Oilseeds 
28  Diamides  cyantraniliprole (Exirel®)  1  Canola 
2  Forage brassicas 
31  Nucleopolyhedrovirus  NPV of H.zea or H.armigera – (eg. Gemstar®, Vivus® Max)  no limit but avoid season long use of low rates  Oilseeds 
UN  Clitoria ternatea extract  clitoria ternatea extract (Sero-X)  not specified  Brassicas 
UNM  Paraffinic spray oils  paraffinic oil (eg. Parachute®)  not specified when used in conjunction with Bt sprays  Canola 

URL: https://croplife.org.au/resources/programs/resistance-management/canola-crops-forage-brassica-diamondback-moth/
Content last updated: July 22, 2026

CropLife Australia’s Resistance Management Strategies provide a guide for crop protection product rotation through product groups. The strategies are a useful tool that supports farmers’ adoption of resistance management. All crop protection products must be handled and applied strictly as specified on the product label or APVMA permits.

These Resistance Management Strategies do not replace product labels. They are a guide only and do not endorse particular products, groups of products or cultural methods in terms of their performance. It is important to check with the Australian regulator’s (APVMA) product database for contemporary information on products and active constituents. The database can be sourced through www.apvma.gov.au

The information given in this strategy is provided in good faith and without any liability for loss or damage suffered as a result of its application and use. Advice given in this strategy is valid as at 22 July 2026. All previous versions of this strategy are now invalid.