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Effects of nitrogen fertilizers on the aluminium contents of mature tea leaf and extractable aluminium in the soil

DOI: 10.1007/BF02370429

ABSTRACT Increasing rates of nitrogenous fertilizer decreased the aluminium contents in mature leaf of tea but increased the extractable
soil aluminium in the 0–30 cm soil depth. Use of NPKS 25:5:5:5 or NPK 20:10:10 did not affect the order of responses. Different
rates of potash had no effect on leaf aluminium levels. The concentrations of aluminium in the mature leaf were well above
the minimum required for tea nutrition. The increase in extractable soil aluminium due to higher nitrogen rates in part explains
the generally low potassium and calcium contents in the leaf and soil.

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