Abstract

                                Field experiments were conducted in summer and Kharif seasons of 1982 at Tamil Nadu Agricultural University to study the nitrogen use economy and efficacy of herbicides in relation to nutrient uptake and yield of irrigated sorghum Var. Co. 24. Application of pre- emergence atrazine at 0.5 Kg:ha or 0.25 Kg/ha followed by one late manual weeding (35 DAS) registered higher grain yield, nutrients uptake by the crop as well as reduced nutrient removal by weeds in both the seasons at all nitrogen levels. Applcation of 60 Kg N/ha in equal splits (50% Basal + 50% at 30 DAS) recorded higher grain yield of 5866 and 4773 Kg/ha for summer and kharif seasons respectively and it was on par with 90 Kg N/ha indicating the economic utilization of nitrogen with pre-emergence application of atrazine.

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