Diagnosing iron deficiency in field peas
Iron (Fe) deficiency is often seen on highly calcareous soils in the Esperance mallee, particularly in late July when soil temperatures are low and there is excess water in the soil.
What to look for
- Deficiency is most likely on soils with free lime, often in patches or wheeltracks where waterlogging is worse.
- Despite being chlorotic, leaves remain relatively healthy and recover completely with the return of warmer drier weather.
Paddock
- Plants with pale green to intense yellow new leaves that contrast with healthy green old leaves.
Plant
What else could it be
| Condition | Similarities | Differences |
|---|---|---|
| Diagnosing sulphur deficiency in field peas | Chlorotic young growth. | New leaves are yellow rather than white, deficient plants are stunted, and deficiency is more likely sandy soils. |
| Diagnosing group B herbicide damage in field peas | Chlorotic young growth | The growing point and new leaves are yellow and become necrotic. |
| Diagnosing virus damage in field peas | Chlorotic young growth | Distribution is patchy, not associated with a soil type. |
| Diagnosing manganese deficiency in field peas | Chlorotic young growth | Leaf interveinal chlorosis and tendrils roll inwards and die back from the ends. |
Where did it come from?
Soil ph
- There are a complex series of interactions in the soil that combine to reduce the availability of iron to plants. The deficiency will usually occur in plants grown on soils with a pH above 7.0 if the soil aeration is reduced slightly and temperatures are cold.
Management strategies
- No yield responses to iron have been measured in the field to justify soil application.
- Where symptoms occur, particularly in cold and wet conditions, they are frequently eliminated by increased soil and air temperatures.
- Foliar sprays will remove the symptoms where they occur in highly calcareous or limed soils, but there is no yield benefit.
See also
Further information
Where to go for expert help
Page last updated: Wednesday, 13 May 2015 - 2:11pm