Insect pest risk

High risk Moderate risk Low risk
Establishment pests
  • Weedy fallows and volunteers.
  • History of establishment pests.
  • High level of retained stubble.
  • Crop emergence and establishment slowed by cool, dry or wet conditions.
  • High incidence of parthenium weed in close proximity to seedling crops (Central Queensland). High risk of Tobacco Streak Virus (TSV) being transmitted by thrips.
  • Crop rotations with peanuts increases risk of white fringe weevil.
  • Sunflowers following wheat, sorghum or pasture may have a higher prevalence of black scarab beetles.
  • Control of weeds in fallow at least 3 weeks prior to sowing will reduce the risk of cutworm build up. 
 Seed dressings protect seedlings unless pest pressure is extreme.
Rutherglen bug
  • Repeated influxes of RGB in spring require continual monitoring and repeated treatment to prevent large infestations in heads.
  • Abundant local weed hosts (fleabane, pigweed) as a result of wet winter.
  • Large immigrations of RGB from inland areas.
 Moisture stress makes budding crops more susceptible to damage. Locally dry winter resulting in low RGB populations + little or no immigration from long distance sources.
Helicoverpa
  • High populations of large larvae feeding at budding.
  • Weeds in crop supporting helicoverpa larvae that move onto the crop as large larvae and damage buds.
 Feeding damage to the back of heads predisposes the plant to secondary head rots in the event of wet weather.
Slugs and snails
  • Annual rainfall >500 mm
  • Above average spring–autumn rainfall
  • No till stubble retained
  • Previous paddock history of slugs and snails
  • Summer volunteers and weeds
  • No sheep in enterprise
  • 450-500 mm annual rainfall
  • Tillage or burnt stubble only
  • Sheep on stubble
  • <450 mm annual rainfall
  • Drought
  • Both tillage and burnt stubble
  • No volunteers and weeds

Pest incidence

Pest Crop stage

Emergence

Vegetative

Budding

Flowering

Grainfill
False wireworm Damaging Present
True wireworm Damaging Present
Cutworm Damaging
Thrips Damaging Present
Black scarab Damaging Present
Cockroaches Damaging Present
Earwigs Damaging Present
Black field cricket Damaging Present Damaging
Slugs and snails Damaging Damaging
Loopers Present Damaging Damaging
Helicoverpa Damaging Damaging Present Present
Greenhouse whitefly Present Present Present Present
Silverleaf whitefly Present Present Present Present
Rutherglen bug Present Damaging Damaging Damaging
Green vegetable bug Present Damaging Damaging Damaging

 

Present Present in crop but gen­er­ally not dam­ag­ing
Dam­ag­ing Crop sus­cep­ti­ble to dam­age and loss

Key IPM considerations for sunflowers

  • Sunflowers are susceptible to seedling damage because damaged sunflower seedlings lack the capacity to regrow or tiller.
  • The use of synthetic pyrethroids to control RGB will kill beneficial insects that may otherwise suppress helicoverpa and looper populations. Regular monitoring is essential.
  • Bees are important pollinators of sunflowers. Consider bees in management options and only  spray late afternoon when bees are less active
  • Snails may also cause grain con­t­a­m­i­na­tion at har­vest

Further information

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