EFFECT OF NITROGEN AND POTASSIUM ON GROWTH, DEVELOPMENT AND SUGAR ACCUMULATION IN TROPICAL SUGAR BEET

Abstract

A field experiment was conducted at the research farm of the Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh from November 2012 to April 2013 with four levels of nitrogen viz. 0, 50, 100 and 150 kg N ha-1 in combination with four levels of potassium viz. 0, 60, 120 and 180 kg K ha-1 to findout the optimum doses of nitrogen and potassium for optimum growth, development and sugar accumulation in tropical sugar beet in Bangladesh. Plant height, number of leaves per plant, LAI and crop growth rate (CGR) significantly increased with the increase in nitrogen level but the increase was not significant with increased potassium level. The combination of 150 kg N and 180 kg K ha-1 resulted in the highest number of leaves per plant and LAI. Increasing nitrogen levels led to decrease in TSS content in juice and sucrose content in root. The TSS content increased with increasing potassium level up to 120 kg K ha-1 . The potassium levels and the combination of nitrogen and potassium levels did not show any significant effect on sucrose content in root. Increasing nitrogen and potassium levels caused reduction in juice purity. For optimum growth, development and sugar accumulation in tropical sugar beet in Bangladesh the nitrogen and potassium requirement of the crop seems to be more than 150 kg N and 180 kg K ha-1 .