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Site Specific Nutrient Disorders |
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Magnesium Deficiency
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Areas affected
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Magnesium deficiency is found both in acid soils (Kerala, Andhra Pradesh) and
alkaline soils (Tamil Nadu, Gujarat) where cassava is cultivated in India.
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Deficiency symptoms
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The lower leaves of magnesium deficient plants show interveinal chlorosis. At
first the tips and margins of these lower leaves develop chorotic symptoms.
Later on the symptoms spread inward covering the entire portion of the area in
between the veins. In areas where severe magnesium deficiency is seen, the
leaves become necrotic and develop whitish colour. Magnesium deficiency symptoms
are common in soils where there is excessive amount of potassium.
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Magnesium deficiency symptom on cassava leaf
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Magnesium deficient plant
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Corrective measures
In areas where magnesium deficiency is found, apply 20-50 kg Mg / ha as MgO,
dolomite or MgSO4. If MgO and dolomite are used, broadcast and incorporate
before planting since they are relatively insoluble. If MgSO4 is used, apply it
as band application near plants shortly after planting since it is soluble. |