INFLUENCE OF ORGANIC AND INORGANIC FERTILIZERS ON THE YIELD OF SOME ARABLE CROPS IN SOUTHWESTERN NIGERIA
Okore I.K1*., O. P. Aiyelari2, H. Tijani-Eniola2,
1Rubber Research Institute of Nigeria, P.M.B.1049, Benin City, Edo State. 2Department of Agronomy, University of Ibadan, Ibadan, Nigeria.
*Corresponding author’s Email addresses: iko7796@yahoo.co.uk; aiyelari@yahoo.com
Accepted on April 28, 2004
Abstract
Two field experiments were conducted at the Teaching and Research Farm of the University of Ibadan from 1995 through 1999 cropping seasons to evaluate the effect of organic and inorganic fertilizers on the yield of maize (Zea mays L.), melon (Citrullus vulgaris L) and cassava (Manihot esculenta Crantz). The first experiment consisted of organic (a mixture of domestic waste and cow dung applied at 10 t ha-1), inorganic (150 kg N ha–1 supplied as urea (UR) and 50 kg P ha–1 as single super phosphate) and a mixture of the organic and inorganic fertilizers. The second experiment evaluated the effect of two types of organic industrial waste: palm kernel de-oiled cake (PKDOC) and shea nut de-oiled cake (SNDOC) fortified with various levels of inorganic fertilizers {Urea (UR) and Sokoto rock phosphate (SRP)} compared with NPK 15:15:15 on grain yield. The highest mean maize grain yield (2.78 t ha-1) for 1995 and 1996 was obtained from plots treated with a mixture of organic and inorganic fertilizers. Plots treated with organic and inorganic fertilizers combined and those that received organic fertilizer alone, significantly (P £ 0.05) outyielded the control. Combined application of organic and inorganic fertilizer resulted in a yield increase of 43 and 32% in 1995 and 1996, respectively in melon seed compared with organic fertilizer application. However, fertilizer types had no-significant effect on cassava fresh tuber yield. The result of these studies indicated that a mixture of organic and inorganic fertilizers could be more beneficial to crops than the use of either pure organic or inorganic fertilizer under the tropical soil condition.