Crop yield and the fate of nitrogen and phosphorus following application of plant material and feces to soil

Organic materials are the most important sources of nutrients for agricultural production in farming systems of semi-arid West Africa. However, reliance on locally available organic nutrient sources for both crop and livestock production is rapidly becoming unsustainable. A series of feeding and agronomic trials have been conducted to address the role of livestock in sustainable nutrient cycling. This paper reports results of a greenhouse study that evaluated the effects of applying crop residue and browse leaves, or feces derived from these feeds, at equal organic-N application rates (150 kg h

From cassava to gari: Mapping of quality characteristics and end-user preferences in Cameroon and Nigeria

User's preferences of cassava and cassava products along the value chain are supported by specific root quality characteristics that can be linked to root traits. Therefore, providing an evidence base of user preferred characteristics along the value chain, can help in the functional choice of cassava varieties. In this respect, the present paper presents the results from focus group discussions and individual interviews on user preferred quality characteristics of raw cassava roots and the derived product, gari, ‐ one of the major cassava products in Sub Saharan Africa ‐ in major production and consumption areas of Cameroon and Nigeria. Choice of cassava varieties for farming is mainly determined by the multiple end‐uses of the roots, their agricultural yield and the processing determinants of roots that support their major high‐quality characteristics: size, density, low water content, maturity, colour and safety. Processing of cassava roots into gari goes through different technological variants leading to a gari whose high‐quality characteristics are: dryness, colour, shiny/attractive appearance, uniform granules and taste. Eba, the major consumption form of gari in Cameroon and Nigeria is mainly characterized by its textural properties: smoothness, firmness, stickiness, elasticity, mouldability. Recommendations are made, suggesting that breeding will have to start evaluating cassava clones for brightness/shininess, as well as textural properties such as mouldability and elasticity of cassava food products, for the purpose of supporting decision‐making by breeders and the development of high‐throughput selection methods of cassava varieties. Women are identified as important beneficiaries of such initiatives giving their disadvantaged position and their prominent role in cassava processing and marketing of gari

Effect of improved fallow systems on soil chemical properties and crop yield in the rain forest of southeastern Nigeria

In most of sub-Saharan Africa, there has been shortening of fallow periods to less than 10 years by farmers. In southeastern Nigeria, fallow periods have been reduced to less than 5 years due to population pressure. Marginal lands are being brought under cultivation. Under these circumstances, there is need for soil and crop management options to improve productivity. The study site is in the humid forest zone with an average elevation of 10m a. s. l. and receives a mean annual rainfall of 2400 mm, usually in a monomodal distribution lasting from March to November. The soils are highly weathered and acidic with Ultisols of pH ranging from 3.5 to 6.0 and mineralogy dominated by low activity clays with low cation exchange capacity (CEC) and low base saturation. The soils have a low organic matter (0.5-3%) and consequently low nutrient reserve. Two experiments were conducted between 1996 and 2000 with improved fallow systems. Soil chemical properties under the improved fallow systems, were significantly improved within a short period of time while cassava and maize yields were greatly increased. Although the Tephrosia mulch showed a tendency of soil acidification in the present study, the lab lab fallow either with or without sheep grazing, led to increases in soil pH, organic carbon (OC), nitrogen (N), phosphorus (P), and potassium (K). The adoption of these fallow systems by farmers will depend on their profitability and sustainability in these fragile tropical ecosystems.Dans la majorité des zones subsahariennes d’Afrique, les paysans ont réduit la durée de la jachère à moins de dix années. Mais dans le SE du Nigeria, la pression démographique est telle que la jachère a été réduite à moins de 5 ans. Des terres marginales ont été mises en culture: d’où la nécessité de définir des techniques de production capables d’améliorer la productivité des sols. L’étude eut lieu dans une zone de forêts humides, à 10 m d’altitude et 2400 mm de pluie monomodale, entre mars et novembre. Les sols sont des ultisols très acides, profondément altérés, à argile kaolinitique à faible capacité d’échange de cations et faible saturation en bases. Ces sols sont pauvres en matières organiques (0,5 à 3 % de MO) et ont par conséquent peu de réserve de nutriments. Deux essais ont été conduits de 1996 à 2000 comparant divers systèmes de jachères. Sous les jachères améliorées, les propriétés chimiques des sols ont été significativement améliorées en une courte période et les rendements en manioc et maïs largement augmentés. Bien que le paillage de Tephrosia a entrainé une tendance à l’acidification dans cet essais, la jachère à Lablab, avec ou sans pâturage par les moutons, a amené une augmentation du pH, du taux de MO, de l’azote, du P et K. L’adoption par les paysans de ces techniques va dépendre de la rentabilité et de la durabilité de ces techniques dans ces écosystèmes tropicaux très fragiles

The Influence Of Lablab (Lablab purpureus) On Grain And Fodder Yield Of Maize (Zea mays) In A Humid Forest Region Of Nigeria

The influence of lablab on maize grain and fodder (stover) yield was investigated during the early and late cropping seasons of 1998 and 1999, at Onne, in the humid forest zone of Nigeria. Lablab was simultaneously planted in maize the same day and also undersown in maize at 2, 4, 6 and 8 weeks after maize planting (WAP) while sole maize and sole lablab were used as control. Simultaneous planting reduced maize grain yield by 40-63% relative to the sole maize crop while higher grain yield was obtained when undersowing of lablab was delayed beyond 2 WAP. Unlike maize grain yield, highest lablab DM fodder yield was obtained when maize and lablab were simultaneously planted, and declined progressively with delayed undersowing of lablab while maize fodder yield was not affected by time of lablab undersowing. Time of lablab undersowing positively influence total fodder (maize + lablab) yield. When fed to livestock, rate of digestibility was higher in lablab fodder than the maize fodder, indicating that lablab fodder enhanced the digestibility of lablab-maize forage. Undersowing of lablab in maize not latter than 4 WAP, effectively controlled weed infestation in the intercrops than undersowing later. Journal of Applied Sciences and Environmental Management Vol. 8 (2) 2004: 45-5

Soldiers without an army? Patronage networks and cohesion in the armed forces of the DR Congo

This article analyzes the effects of patronage networks on cohesion in the Armed Forces of the Democratic Republic of the Congo. It shows that while patronage networks provide support to individual military personnel, they undermine both peer and commander–subordinate bonding. They promote unequal service conditions and statuses and link these to extra-unit and extra-military forms of social identification, which are further reinforced by soldiers’ living and generating revenue among civilians. Furthermore, they impair meritocracy and frustrate the extent to which commanders live up to their subordinates’ expectations. As they fuel internal conflicts, often around revenue generation, and foster bad service conditions and distrust toward the political and military leadership, patronage networks also undermine institutional cohesion. The article concludes that cohesion formation in the FARDC follows different patterns than in well-institutionalized and well-resourced militaries. Given that cohesion impacts combat performance and norm enforcement, these findings are relevant for defense reform efforts and military cooperation