The present investigation was carried out at the Experimental Farm of Sakha Agricultural Research Station, Agricultural Research Center, at Kafr El- Sheikh Governorate, Egypt during 1999/2000 and 2000/2001 seasons. Two field experiments were conducted to study the effect of three nitrogen rates i.e., 40, 65 and 90 kg N/fed. (as soil application) and five treatments of foliar spraying with urea at the rate of (50 g/l) i.e., cont., one, two, three and four foliar on yield, yield components and quality of sugar beet as well as to minimizing costs of fertilization and environmental pollution. The experimental design was strip- plot design with four replications. The main results of this investigation could be summarized as follows:
Increasing nitrogen fertilizer as soil application up to 90 kg N/fed. and repeating foliar application with urea solution significantly increased root length and diameter, dry matter accumulation/plant, root and top yields/fed. as well as sugar yield/fed. in both seasons. The inverse was true in TSS, sucrose and juice purity percentages. Whereas, raising soil application of nitrogen from 40 to 90 kg N/fed. and foliar spraying with urea caused a marked decrease in the previously mentioned traits.
Generally, it can be concluded that soil application of nitrogen fertilizer at the rate of 65 kg N/fed. and foliar spraying sugar beet plants three times with urea solution at the rate of (50 g/l) could be recommended for optimum root and sugar yields per unit area as well as decreasing fertilizer costs under the condition of the present study.