Effect Of Time And Depth Of Application Of Waste Ammonia Produced By Khartoum Refinery On Forage Sorghum (sorghum Bicolor L.)

Abstract

A field experiment was conducted at the University of Khartoum farm, Shambat, Sudan, for two seasons (2006-2007)and (2007-2008).The objective of the study was to investigate the effect of the time and depth of application of aqueous waste ammonia, as a nitrogen fertilizer, on growth and yield of forage sorghum (Sorghum bicolor L. ) and its efficiency as compared to urea fertilizer. The split block design was adopted for the layout of 76 experimental plots representing 19 treatments replicated four times each. Eighty kg N/ha of urea and of ammonia were applied at different depths: 5, 10, and 15cm into the soil at different times of application: one week before sowing (T1), two weeks after sowing (T2) and four weeks after sowing (T3). The results revealed that the 15cm depth of application significantly (p ≤ 0.05) increased the fresh and dry weight of the plant for both urea and ammonia through the two seasons as compared to other

depths. The results of the experiment also showed that T2 was found to be the best time of nitrogen fertilizer application for both urea and ammonia compared to T1 and T3. Leaf N, P and K were significantly (P ≤ 0.05) increased by application of both ammonia and urea. However, the results showed that yield was better in urea than that of ammonia, but the differences were quantitatively small (about one ton fresh weight ha-1). In conclusion, waste ammonia produced by Khartoum Refinery can be disposed of safely in soil by using it as a cheap nitrogen fertilizer for forage sorghum and that it is practically as efficient as urea fertilizer.