kone, a. w. université nangui abrogoua - ufr des sciences de la nature, unité de recherche « gestion durable des sols », Côte d’Ivoire , tondoh, j. e. wascal competence centre, Burkina Faso , tondoh, j. e. université nangui abrogoua - centre de recherche en ecologie - ufr des sciences de la nature, Côte d’Ivoire , aduramigba-modupe, v. o. obafemi awolowo university - institute of agricultural research training, Nigeria , deleporte, p. centre de coopération internationale en recherche agronomique pour le développement (cirad) - forêt/ur2pi, France , orendo-smith, r. stellenbosch university - department of soil science, South Africa , brunet, d. institut de recherche pour le développement (ird) - umr eco sols, France

LEGUME AND MINERAL FERTILIZER DERIVED NUTRIENT USE EFFICIENCIES BY MAIZE IN A GUINEA SAVANNAH OF COTE D’IVOIRE

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This paper deals with reclamation of marginal savannah lands in central Côte d’Ivoire. It aimed at assessing legume-derived nutrient use efficiencies (NUE) by maize and quantifying the importance of these legumes as nutrient source relative to inorganic fertilizers. Experimentations included eight treatments in a RCB design (n=3): four herbaceous legume-maize successions and four continuous maize cropping with urea (U, 46% N, 50 kg ha^-1), triple superphosphate (TSP, 45% P, 30 kg ha^-1), urea+triple superphosphate (U+TSP) and a control. The NUE was estimated through Apparent Recovery (AR). In addition, the N- and P-fertilizer replacement indices (N-FRI and P-FRI) by legumes, which express their importance as source of N and P for maize relative to inorganic fertilizers, were estimated. The AR of Nlegume and Plegume by maize varied from 16.6 to 29.1 % and from 29 to 62 %, respectively while those of Nurea and PTSP were only 12 and 4.3 % on U and TSP plots, respectively. Values of legume N-FRIs and P-FRIs suggest that the legumes’ impact on maize yield corresponded to that of the application of 131 to 195 kg urea ha^-1 and 27.5 to 96 kg TSP ha^-1, respectively. Compared to U and TSP, legume-derived nutrients were more efficiently used by maize, particularly nutrients from P. phaseoloides.

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Agroecology , Crop nutrition , Ferralsols , Legumes , Marginal land reclamation , Nutrient sources

Agronomie Africaine

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