Abstract

Soil fertility decline is a major constraint to crop production in sub-Saharan Africa due to continuous cropping of maize without an adequate fertilization. The main objective of the present study was to evaluate the effectiveness of several fertilization regimes in monocrop and intercrop systems in a Sub-Saharan Africa region. The study was carried out in a savannah region in D.R. Congo at two locations. The treatments included a control (NoF), inorganic application consisting of nitrogen-phosphorus (NP), organic application of Entada abyssinicaand Tithonia diversifolia, and a combination of organic and inorganic application involving NP with E. abyssinica (N + E) and NP with Tithonia diversifolia (NP+T). In general, maize mixed with soybean had significantly lower grain yields compared to sole maize plots. Maize in monocrop fertilized with NP combined with E. abyssinica (NP + E) or T. diversifolia (NP+T) produced the highest grain yields at both sites. Application of T. diversifolia and E. abyssinicaalone increased the grain yield by more than three–fold in monocrop trails and more than twice in the association trials compared to the control. The number of kernels per cob was the main agronomic factor associated to the grain yield differences. Application of organic material, especially E. abyssinica and T. diversifolia should be recommended to smallholder farmers as a short term cost efficient fertilization practice.

Key words: Inorganic fertilizer, organic fertilizer, Entada abyssinica, Tithonia diversifolia, sub Saharan African, grain yield