Insect pest risk

High risk Moderate risk Low risk
Earth mites and lucerne flea
  • Paddocks not treated for red legged earth mite (RLEM) in the previous season.
  • Seasonal forecast is for dry or cool, wet conditions that slows crop growth.
  • Pasture going into crop.
  • History of high mite pressure.
  • Crops established with minimum tillage may have more RLEM and lucerne flea.
  • Isolate lentil crops from pastures and capeweed to minimise RLEM damage.
  • Intensive grazing of pastures, the previous spring
  • Higher sowing rate used.
  
Aphids
  • High rainfall and irrigated areas have higher virus risk.
  • ‘Green bridge’ e.g. lucerne, medics, clover, volunteer pulses and broadleaf weeds – is a potential source of virus-transmitting aphids.
  • Wet autumn and spring promotes the growth of weed hosts (when weed hosts dry off, aphids move into crops).
  • High intensity rain during crop growth can suppress aphids.
Native budworm
  • Wet winters in inland breeding areas.
  • Moth flight before or during flowering/podding.
  • Dry winters in inland areas.
  • High beneficial insect activity.
  • No migration of moths (determine with trapping and monitoring programs).
Etiella
Late crops can be subject to first and second generations of Etiella. Moisture stress at early podding. Early planting ensures that most pods are set before moth activity occurs in spring.
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
RLEM Damaging Present
Lucerne flea Damaging Present
Cutworms Damaging
Slugs and snails* Damaging Damaging
Aphids Damaging Present Present
Thrips Present
Loopers Damaging
Native budworm Present Damaging Damaging Damaging
Etiella Damaging Damaging Present
 * 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 lentils

  • Economic damage is most likely to occur during establishment and from flowering until maturity.
  • Lentils are useful as a rotation crop with canola and winter cereals as lentils can suppress red legged earth mite and blue oat mite populations (if weeds are also controlled). However, lentils will suffer damage from earth mites if populations are high.
  • Lentils are tolerant of some foliar damage and compensate by producing secondary shoots
  • Etiella degree-day model assists in forecasting moth flight activity (see the Etiella page for more details). Control of moths, before they lay eggs on developing pods, is critical to Etiella management.
  • Transmission of viruses by aphids, 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. Where virus transmitting aphids are a threat – refer to management options in insects as virus vectors
  • RLEM has been found to have high levels of resistance to two synthetic pyrethroids – bifenthrin and alpha-cypermethrin

More information

Best bet strategy for managing pests in winter pulses

Print Friendly, PDF & Email