Alley cropping of maize and Gliricidia sepium in the Sudanese Sahel Region: Some technical feasibility aspects

TR Number
Date
2000
Journal Title
Journal ISSN
Volume Title
Publisher
Taylor and Francis Ltd
Abstract

An association in an alley cropping experiment of a short-term maize variety and a tree legume (Gliricidia sepium) adapted to the Sudanese Sahel region was studied from the point of view of the nitrogen balance and plot yields. Isotopic labeling applied in the field enabled the contribution to maize nitrogen nutrition from different nitrogen sources (fertilizer, prunings, and soil) to be quantified. For equal cultivated areas, alley cropping provides a maize yield greater than that of maize grown in pure stand without nitrogen fertilizer. However this yield is only 40% of that obtained in pure stands with fertilizer nitrogen. Alley cropping gives a very favourable Land Equivalent Ratio (LER) of 0.90 and 1.58 compared with N-fertilized and non-N-fertilized plots, respectively. These LERs demonstrate the increased biological efficiency of the cultivated soil in an agroforestry system. The percentage of the total nitrogen in the maize coming from prunings (Nfdp) varies between 30 and 35% and the true coefficient of nitrogen utilization of the prunings (TCUp) varies from 15-25%. In the environment of central Senegal, the percentage of total nitrogen of G. sepium coming from N2 fixation is quite low (Ndffix = 25%), and consequently, in the maize, the nitrogen coming from N2 fixation (Ndffix) is only 8%. It is therefore necessary to improve the efficiency of nitrogen fixation of G. sepium in this zone to assure the sustainability of the agroforestry system. ---Journal/Author's Abstract

Description
Metadata only record
Keywords
Agroforestry, Agriculture, Soil fertility, Fertilization, Nitrogen, Utilization, Nitrogen fixation, Ecosystem
Citation
Arid Land Research and Management 14(4): 317-327