Diagnosing frost in field peas

Of the pulses, field peas are more vulerable to frost due to thin pod walls and exposure of flowers to frost. 

Mottled pods
Shrivelled and aborted seed
Field peas re-shooting after a frost

What to look for

    Paddock

  • Low lying areas, light-coloured soil types, dry soil and areas with more retained stubble are likely to be more damaged.

    Plant

  • Plants with wilted upper foliage that shrivels and dies, or blistered pods.
  • These frozen upper stems become discoloured (dark green directly after thawing) and associated foliage shrivels and dies.
  • Often the damaged tissue (stem and pods) will take on a brown colour due to bacterial fungal infection.
  • Stems have surface splits that turn brown with a mushy interior.
  • Pods have pale surface spots or blisters and brown mushy lesions.
  • Developing pods abort and fall off.
  • Developing seed may abort.
  • Unaffected parts of the plant grow, flower and set seed if there is sufficient time and soil moisture (refer to Figure 3).

Where does it occur?

Temperature
Temperature
  • Frost damage occurs when night air temperature falls below -2°C.
  • Field peas become more susceptible throughout flowering and bud formation when the plant is rapidly growing.

Management strategies

  • Frost damage is irreversible, however managing a crop to only avoid frost will come at a yield cost and potentially increased disease risk. It is advisable that after a frost event, to make note of the location and severity, as this will help to inform future crop choice and post frost decisions.

How can it be monitored?

  • Check low lying, light coloured soil types and known frost prone areas first, then check other areas.
  • To identify frost damage check for flowers failing to set pods and open developing pods that have a scarred surface to check for mushy, shrivelled or abnormal grain.

Further information

Where to go for expert help

Mark Seymour
+61 (0)8 9083 1143
Page last updated: Monday, 27 November 2017 - 12:40pm