Insect pest risk

High risk Moderate risk Low risk
Establishment pests
  • History of high mite pressure.
  • Following crops that host earth mite populations (e.g. pastures).
  • Cool, dry or wet conditions (slow crop emergence and seedling growth).
  • Weedy crop and/or crop edges hosting red legged earth mite (RLEM) that may move into germinating crop.
 Following a crop with reduced hosting capacity for RLEM (e.g. faba bean, narrow-leafed lupin and lentils).
  • Following a crop in which RLEM reproduction is low, or where RLEM have been controlled in prior to summer diapause (e.g.  chickpeas, winter cereal, albus lupins).
  • Rapid emergence and establishment of seedlings.
Native budworm
  • Wet winters in breeding areas of central Australia + suitable weather conditions that bring moths from west to east result in spring migrations.
  • Repeated influxes of moths over long periods, resulting in need for continuous monitoring and potentially repeat infestations.
  • Broadleaf weeds hosting cutworm and helicoverpa that then move into the crop as large, damaging larvae.
  • Hot weather in spring (can cause small larvae to burrow into pods).
  • Wet harvest weather (pods are ‘softer’ for longer and susceptible to damage right up to harvest).
  • High beneficial insect activity.
  • Dry winters in breeding areas (low source population).
  • Absence of frontal wind systems that provide opportunities for migration.
Aphids and virus
  • High rainfall (>500 mm) or irrigation district.
  • Proximity of crop to ‘green bridge’ (potential source of aphids and virus).  Examples include lucerne, medics, clover, volunteer pulses and broadleaf weeds.

 
  • Wet autumn and spring (promotes growth of weed hosts).
  • Sowing into standing stubble reduces aphid landing.
  • Seed dressings may provide some benefit  against persistent viruses.
  • Rapidly closing canopy that ‘shades’ out unthrifty, virus infected plants – limiting further transmission.
  • Sowing virus-resistant cultivars and certified virus-free seed.
  • Early sowing allows flowering before aphid populations peak.
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
  • Tillage and burnt stubble
  • No volunteers and weeds

Pest incidence

Pest Crop stage

Emergence/Seedling

Vegetative

Flowering

Podding

Grainfill
Earth mites Damaging Present Present
Lucerne flea Damaging Present
Cutworms Damaging
Slugs and snails* Damaging Damaging
Aphids (virus vectors) Damaging Damaging Present Present
Thrips Present Present
Helicoverpa Present Damaging Damaging Damaging
* Snails may also cause grain con­t­a­m­i­na­tion at har­vest
Present Present in crop but gen­er­ally not damaging
Dam­ag­ing Crop sus­cep­ti­ble to dam­age and loss.

Key IPM strategies for faba beans

Both species of helicoverpa can cause damage to pods and developing seed, resulting in yield loss and increased defective seed.

  • In the northern region and in irrigation areas of NSW, both species may occur in faba beans, depending on the season. Species composition is influenced by the time of year. In temperate regions (southern Queensland, NSW) the majority of the H. armigera population over-winter from mid-March onwards and emerge during September/October. H. punctigera is usually the dominant species through September.
  • The Helicoverpa Diapause Induction and Emergence Tool uses current day length and temperature data to predict the timing of the emergence of moths from overwintering pupae.
  • Where both native bud­worm and corn ear­worm occur, be aware that insec­ti­cide resis­tance in corn ear­worm can affect the effi­cacy of synthetic pyrethroids and organophosphates.

Aphids transmit viruses, such as Bean Yellow Mosaic Virus which causes leaf mottling and plant dwarfing.

  • Transmission of viruses in the early stages of crop growth is most damaging.
  • Virus transmission typically occurs well before aphid colonies are evident.
  • A pre-emptive and integrated management approach (taking into account the risk factors) is required to minimise the impact of virus.

More information:

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