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Site Specific Nutrient Disorders |
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Zinc Deficiency |
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Areas affected |
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Zinc deficiency symptoms are commonly seen both in acid as well as alkaline
soils where cassava is cultivated in India. |
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Deficiency symptoms
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Interveinal chlorosis of younger leaves is the characteristic symptom of zinc
deficiency. First, small white or pale yellow spots or patches appear in between
the veins of leaves. The lobes of leaves become narrow, chlorotic and will curl
upward. In case of severe zinc deficiency, tips of leaves become necrotic. |
Zinc deficiency symptom on cassava leaf |
Zinc deficient plant in acid soils |
Zinc deficient plants in alkaline soils |
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Corrective measures
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Apply 12.5 kg Zn / ha as ZnSO47H2O at planting or incorporate ZnO before
planting (cassava). If the problem is found to be less severe, foliar
application of 1-2% solution of ZnSO47H2O is very effective. Under alkaline
conditions of Salem and Gujarat, for cassava, stake treatment is recommended
since Zn supplied to soil is precipitated at high pH (6.7-8.0). Under such
situations, dip the stakes of cassava in 2-4% solution of ZnSO47H2O for 15
minutes prior to planting or apply 1-2% solution of ZnSO47H2O as foliar spray. |