Nitrogen Fertilizer Effects on Quality of Fodder beet (Beta vulgaris var. Crassa)

摘要

A field experiment was carried out for two consecutive seasons (2007/08 – 2008/09), at the Demonstration Farm of the College of Agricultural Studies (Shambat), Sudan University of Science and Technology, to study the effect of nitrogen fertilization on quality of three fodder beet cultivars . Nitrogen treatments at a rate of 0, 40, 80 and 120 kg N/ha were assigned to the main plots .Three fodder beet cultivars (Voroshenger, Anisa and Polyproductiva) were allotted to the sub-plots. Nitrogen fertilization reduced dry matter content highly significantly (p<0.01). However, it increased crude protein and ether extract highly significantly (p<0.01) and crude fiber significantly (p<0.05) in the first season and crude protein and nitrogen free extract significantly (p<0.05) in the second season. Leaves exceeded tubers in crude protein, crude fiber and ash highly significantly (p<0.01) while tubers were superior over leaves in dry matter and nitrogen free extract. Tubers without nitrogen fertilization and under 40 and 120 kg N/ha highly significantly (p<0.01) attained the greatest dry matter and nitrogen free extract. Leaves with 40 and 120 kg N/ha recorded the highest crude protein and crude fiber. Leaves under 40 and 80 kg N/ha attained the highest ether extract while those with 80 and 120 kg N/ha recorded the greatest ash contents. Nitrogen, phosphorus, sodium, magnesium, zink and iron were significantly (p<0.05) increased by nitrogen fertilization while calcium was reduced. Sulfur and chloride showed inconsistent response to nitrogen fertilization. Leaves contents of nitrogen, phosphorus, calcium, magnesium and zink were higher than tubers and the reverse was true for potassium and sodium.