Symptoms
The youngest leaves show yellow interveinal discoloration as they come out of the whorl. Mainly the basal part of the leaf is uniformly yellowgreen.
Reasons
Mild Copper deficiency
Copper deficiency in corn is rarely seen. N + S deficiency and cool weather produce symptoms similar to mild copper deficiency.
Leaf streaking can be similar to Fe deficiency.
Copper deficiency made worse by
Organic soils
Chalky soils
Sandy soils
Reclaimed heathland
High nitrogen applications
Copper is important for
Improves fertility
Good cob development
Improves yield
Brings harvest date forward
Yara recommended fertilizers for Copper
YaraVita COPTRAC DUAL
Maize: 0.5 l/ha at the 4 to 8 leaf stage. Water rate: 30 to 200 l/ha. Soil Applied at 3 l/ha. Seed Dressing: 4 litres per tonne.