Diagnosing manganese deficiency in field peas
Manganese (Mn) deficiency has been diagnosed in highly alkaline Esperance mallee soils that are also susceptible to Mn deficiency in cereals.
What to look for
- Early symptoms are pale new leaves with interveinal chlorosis that varies with variety.
- In dun type varieties, new leaves become puckered and narrowly cupped with necrotic tipping on leaves and tendrils.
- In white seed varieties, affected leaves curl downwards along the length of the leaf . Interveinal leaf chlorosis turns into necrotic light brown spotting. Tendrils on new leaves have pale and excessively curled ends.
What else could it be
|Diagnosing iron deficiency in field peas||Chlorotic young growth.||Uniformly pale to white new leaves without distortion or necrosis.|
|Diagnosing sulphur deficiency in field peas||Chlorotic young growth.||Uniformly pale leaves without distortion or necrosis.|
|Diagnosing glyphosate damage in field peas||Young leaf interveinal chlorosis||Plants rapidly wilt and die.|
|Diagnosing group B herbicide damage in field peas||Chlorotic young growth.||The growing point and new leaves become necrotic.|
|Diagnosing virus damage in field peas||Young leaf interveinal chlorosis||Stunted plants; not soil type associated.|
- A foliar spray will correct the deficiency.
- Mn fertiliser is effective but expensive as high rates and several applications are required to generate residual value.
- Seed Mn coating treatments have little effect in correcting deficiency
How can it be monitored?
- Whole plant tests, are not reliable enough to determine deficiency.
- Concentrations of Mn less than 15 mg/kg in youngest mature leaves indicate marginal to deficient levels
- Soil tests are not reliable enough to detect deficient soil prior to sowing.
Page last updated: Wednesday, 13 May 2015 - 2:13pm