Incorporating Short-Season Legumes and Green Manure Crops Into Maize-Based Systems in the Moist Guinea Savanna of West Africa

Abstract

A three-year trial was conducted on a degraded soil in the moist Guinea savanna of northern Nigeria to assess the possibility of improving productivity and economic viability of maize-based systems by incorporating short-season legumes and green manure crops into the cropping pattern. Treatments included double cropping legume-maize systems, full-season sole maize receiving various amounts of nitrogen, green manure crop mucuna (Mucuna pruriens var. utilis) followed by sole maize and a legume-maize system receiving additional rice mill waste. In comparison with full-season maize, the use of early-season cowpea followed by maize improved productivity as well as economic returns of the cropping system, while the use of mucuna, grown as an early-season crop or full-season crop, resulted in poor overall productivity of the system. The addition of rice mill waste as a soil amendment in cowpea-maize systems stimulated maize yields and rice mill waste can form a cheap source of organic inputs for farmers living nearby rice mills. Given the limited growing season of the northern Guinea savanna, it is concluded that timing of field operations is crucial for the successful application of double cropping systems. In addition, high labour requirements are a serious constraint for wide-scale adoption of double cropping systems by small-scale farmers, stressing the need to reduce soil cultivation operations, for example by maintaining a uniform ridge distance for all crops in the rotation. † Corresponding author: c/o Lambourn and Co,

Assessment of nutrient deficiencies in maize in nutrient omission trials and long-term field experiments in the West African Savanna

“…Increases in the yield of cereal crops following the cultivation of legumes relative to those obtained with continuous cereal cropping have been frequently reported in the Guinea savannah (Muhr et al 1999b;Alvey et al 2001;Franke et al 2004;Fofana et al 2005). Often the amount of N and sometimes phosphorus (P) available to cereals improves in legume-cereal rotations.…”

Agronomic Response of Soybean Varieties to Plant Population in the Guinea Savannas of Nigeria

“…It is becoming a major food and cash crop and is widely used in the food and feed industry (Brader, 1998; Sanginga et al, 2002). It contributes to improving soil fertility and reducing Striga infestation on farmers’ fields (Sanginga et al, 2002; Franke et al, 2004). The International Institute of Tropical Agriculture's (IITA) soybean improvement work in Africa started in the mid‐1970s, mainly to increase productivity, which was 0.5 Mg ha −1 (Tefera et al, 2010).…”

Comparative study of earthworm communities, microbial biomass, and plant nutrient availability under 1-year Cajanus cajan (L.) Millsp and Lablab purpureus (L.) Sweet cultivations versus natural regrowths in a guinea savanna zone

“…Most of the works dealing with herbaceous legumes in guinea savannas of West Africa focused on the availability of N and the yield of cereal crops (Tian et al 2000;Fofana et al 2005;Franke et al 2004). However, very few studies focused on the impacts of the legumes on soil invertebrates, particularly earthworms (Blanchart et al 2006).…”