A synthesis of results from the savanna zone of West Africa suggests that cowpea rotation can be considered to be an effective resource management technology in cereal-based systems. Part of the N requirement of cereal crops can be satisfied by cowpea crop rotation. Furthermore, benefits of cowpea rotation are sometimes higher than expected based on the N content of the cowpea crop alone. Reasons for this include substantial root biomass and N, substantial N-sparing by the legume, and other benefits ...

Plant breeders face the difficult task of having to select for traits that are often under complex genetic control and subject to edapho-climatic influences. Electrophoresis of protein extracts from plant tissue, using different kinds ofsupport media and buffer systems, allows separation of the multiple forms ofenzymes (isozymes) on the basis of charge and/or molecular size. The resulting polymorphisms are useful as genetic markers. Isozyme analysis is a powerful technique for estimating genetic ...

A novel method for screening cowpea varieties for resistance to the postharvest insect pest Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) was compared to conventional screening techniques at the International Institute for Tropical Agriculture (IITA) laboratory in Ibadan, Nigeria. The new technique assesses seed resistance by measuring larval feeding activity via electronic sensors. Initial smallscale trials demonstrated that the method could be successfully applied in the laboratory with ...

Cowpea is grown mainly for its protein-rich grains, which is consumed in various forms in sub-Saharan Africa. Average grain yield in farmers' fields is generally low due to a number of biotic and abiotic stresses. The most important of the biotic stress factors causing extensive grain yield losses in cowpea are post flowering insect pests such as the legume pod borer and pod sucking bugs. Availability of varieties with resistance to these pests will be attractive to cowpea farmers as the crop could ...

World per capita food production is today estimated to be about 18% above what it was 30 years ago, but much of Africa is nutritionally worse off today than it was then. Since the vast majority of the poor in Africa depend on agriculture, increasing food production is among the principal means of combating poverty and malnutrition in Africa. The need to rapidly transform agriculture in Africa is understood by the fact that Africa's population growth rate of about 3% per year threatens to reduce ...

Transgenic plant studies have lead to the breakthrough discovery of RNA silencing as a conserved mechanism for gene regulation across kingdoms. Recent molecular genetic studies have revealed a major role for RNA silencing in the formation of silent chromatin, characterized by histone modifications and dense DNA methylation. These epigenetic marks ensure stable, yet potentially reversible, transmission of the silent state of genetic elements such as transgenes and transposable elements through ...