Copper (Cu) deficiency

Copper deficiency is relatively rare especially in irrigated rice systems, but the damage caused by Cu deficiency is important throughout the growth stage of the crop.

Copper (Cu) deficiency affects the metabolic processes of rice plants, specifically photosynthesis and respiration. It can lead to reduced pollen viability and increase in spikelet sterility, thus developing many unfilled grains.

There are several causes of Cu deficiency that include over liming in acidic soils and excessive Zinc in the soil, inhibiting Cu uptake

How to identify ( symptoms)

• chlorotic streaks on either side of the midrib
• dark brown necrotic lesions on leaf tips
• bluish green and chlorotic streaks near the leaf tip
• rolling of new leaves
• New leaves do not unroll and the upper portion of leaves have a needlelike appearance, while the lower portion of the leaf appears normal.
• Plants also have reduced tillering. 
• spikelets become sterile and develop unfilled grains.

How to manage

There is currently no practical field management option for copper deficiency.

Where possible,

1.  dip seedling roots in 1 % CuSO4 suspension for one hour before transplanting

2.  avoid over liming of acidic soils because it may reduce Cu uptake

 

• on Cu-deficient soils, apply CuO or CuSO4 (5−10 kg Cu ha-1 at 5-year intervals) for long-term maintenance of available soil Cu (broadcast and incorporate in soil)