Abstract:
Field experiments were executed for two seasons (2007/08 and 2008/09), at northern and southern Gedarif state with an objective to study the impact of organic manures addition on yield of rain-fed sorghum. The organic fertilizers used were; farm yard manure (FYM) and chicken manure (CM) at levels of 5, 10, 15 and 20 tons/ha for each manure (manually soil incorporated) plus a control. The experiment was sown to Arfa-Gadamak and arranged in a randomized complete block design with three replications. The land was twice ploughed and the crop was sown in rows of 80 cm apart at 20 cm between plants, thinned to 1-2 and 2-3 plant/hole after three weeks at the northern and southern Gedarif respectively, and weeded thrice. Sowing was on the 23rd at Kilo-6 and 26th of July at Doka in the first season, and on the 31Ist at Kilo-6 and the 13th of July at Doka in the second season. The data recorded in both seasons were, plant height, number of heads, grain yield, 1000 grain weight and straw yield. Statistical analysis was carried using MSTATC package and treatment means were compared using the least significant difference at 5 %. Also, the data were economically evaluated to test the efficiency of organic manures on the productivity of rain-fed sorghum and to find the most economical and optimum at level of these manures through assessing their profitability. The results showed that the addition of organic manure resulted in significant differences among all the measured attributes. Irrespective of the first level of farm yard manure (5 tons/ha), other treatments significantly increased sorghum grain yield also. Generally, the application of chicken manure was superior to farm yard manure and the highest grain yield was obtained at 20 ton/ha (1975 kg/ha) followed by 15 tons/ha (1552 kg/ha), 10 tons/ha (1390 kg/ha) and then by 5 tons/ha (994 kg/ha). The economic analysis showed that the chicken manure had both the highest net return and marginal rate of return (584 %) compared to farm yard manure especially at 5 tons/ha and was found as the most economic and optimum level for sorghum production under Gedarif State. From both statistical and economic analysis, the study recommended the application of chicken manure at 5 tons/ha (i.e. 2.1 tons/ feddan) for sorghum production in the Gedarif state.
