Abstract

Field experiments were conducted in summer and Kharif, 1974 under irrigation at Tamil Nadu Agricultural University, Coimbatore, to study the influence of the time and quantity of N application on the N uptake pattern in sorghum (CSH.5). Plant samples were collected from experimental plots at 10 days interval and analysed for N content. Total N uptake and uptake pattern were worked out. Application of N in 4 equal splits viz. basal, on 26th, 52nd. and 80th day after sowing, gave the maximum N uptake. Rate of N uptake gradually increased up to about 40 days of sowing, reaching peak in the 40-50 day period. This coincided with the grand growth period. There was a marked fall in the uptake during the flowering stage. Rate of uptake increased again reaching the second peak in 60-70 day period. A net loss of N from plant was noticed in the period just preceding harvest.

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