Effects of source, level and time of nitrogen application on yield of onion in the Sudan Gezira

Hassan, M. S.

Little difference in the response of onions to the N source, (NH4)2SO4, urea or NH4NO3, was observed. Average yields were higher on plots receiving 190 kg N/ha compared with 95 kg N/ha. The best time for the highest N application was 2 weeks after sowing compared with applications before sowing or a split application at 2 and 4 weeks after sowing.