Demand-Driven Technologies for Sustainable Maize ... - IITA

135materials at zero chemical fertilizer levels. In systems where the majorconstraints to crop production are nutrient limitations, as in soils of theNigerian savanna, single and combined applications of inorganic andorganic materials could be used to increase maize grain production.ConclusionThe study demonstrated that in low input and nutrient defi cientsystems, the application of cow dung or M. pruriens vines could reducethe inorganic fertilizer requirement of a maize crop. The results alsoshowed that under intensive systems, a combination of 5 t of cow dungha -1 and the recommended optimum rate of inorganic fertilizer suchas 120-60-60 could achieve the required high yields. Performance ofyield-related traits varied with the source of organic material. The timingof incorporation of organic materials to ensure maximum benefi t fromnutrients released from the materials needs to be further investigated.ReferencesAnge, A.L., 1995. Development of land use and plant nutrition practicesduring the last 30 years - consequences for the requirements of cropproductivity and plant nutrient supply up to 2010. FAO Fertilizer and PlantNutrient Bulletin 12: 21–48 FAO, Rome.Avnimelech, Y., 1986. Organic residues in modern agriculture. In: the role oforganic matter in modern agriculture. Chen, Y. and Avnimelech, Y. (eds)Developments in plant and soil sciences 25:1–10.Balasubramanian, V. and L.A. Nnadi, 1980. Crop residue management and soilproductivity in Savanna areas of Nigeria. FAO Soil Bulletin 43:106–120Blair, J.G and O.W. Boland, 1978. The release of P from plant material addedto soil. Aust. J. Soil Res. 16: 101–111.Blair, G.J, R.D.B. Lefroy, B.P. Singh and A.R. Till, 1997. Development and useof a carbon management index to monitor changes in soil C pool size andturnover rate. Pp 273-281 In G. Cadisch and K.E. Giller (eds.) Driven bynature: plant litter quality and decomposition. CAB Int. Wallingford, UK.Bouyoucos, C.H., 1951. A recalibration of the hydrometer for makingmechanical analysis of soils. Agron. Journal 43: 434–438.Bray, R. H. and L.T. Kurtz, 1945. Determination of total, organic and availableforms of phosphorus in soils. Soil Science 59: 39–45.Bremner, J.M., 1965. Regular microkjeldahl method for determination of totalsoil N In C.A Black (eds.) Methods of soil analysis Part 2. Agron. 9:1171–1175. Madison, Wisc., USA.Chien, S.H., P.W.G. Sale, and O.K. Freisen, 1990. A discussion of the methodsfor comparing the relative effectiveness of phosphate fertilizers varying insolubility. Fertilizer Research 24:149–157.Daudu, C.K., E. Uyovbisere, I.Y. Amapu, and J.E., Onyibe 2005. Qualitativeand quantitative evaluation of four organic materials as nutrient resourcesfor maize in the Nigerian savanna. Journal of Agronomy (In press).