Adoption and impact of dryseason dualpurpose cowpea in the semiarid zone of Nigeria

In the semiarid region of West and Central Africa, farmers traditionally cultivate different cowpea varieties for grain and fodder. However, the grain yield potential and the availability of good quality fodder is limited by several factors: insects, pests and diseases, low and erratic rainfall, and the long dry season. In the early 1990s, the International Institute of Tropical Agriculture (IITA), in collaboration with the International Livestock Research Institute (ILRI), initiated a breeding program to develop improved cowpea varieties that produce both grain for human consumption and fodder for livestock in the dry season. This paper examines the patterns, levels, rate of adoption, and the impact of one of the most promising varieties (IT89KD-288) introduced to farmers in Kano State, Nigeria. The diffusion and uptake of this variety had been very impressive as it reached over 1500 farmers in 1997, only 4 years after its accidental release to one farmer. The results show that farmers derived substantial benefits from adopting dry-season dual-purpose cowpea. These include food security during a critical period of the year, cash income, crop diversification, fodder, and in situ grazing after harvesting, in periods when the prices of cowpea grain peak, and when good quality fodder is scarce. Dry-season dual-purpose cowpea is thus a profitable technology that will find economic and ecological niches in the mixed crop/livestock farming systems of the semiarid zones of West and Central Africa

Morphological discrimination of Aphis gossypii (Hemiptera : Aphididae) populations feeding on Compositae

Aphis gossypii Glover is a polyphagous aphid pest with a worldwide distribution. However, there is evidence that on a global scale the name A. gossypii is being applied to a number of forms with different life cycles and/or host-plant associations. Morphometric variation of A. gossypii samples from crops and non-cultivated plants in many parts of the world was examined, to determine whether this variation is correlated with the hosts from which the aphids originated. Samples of A. gossypii were collected from Cucurbitaceae and Malvaceae in Europe, and from Compositae in various parts of the world. Morphometric data for 13 parameters measured from 97 clonal lineages (728 specimens) and 27 field-collected samples (313 specimens) were analysed by a series of canonical variates analyses, using the field sample/clonal lineage as grouping factor. Clonal lineages were reared on a common host in controlled conditions to standardize the effect of host and environment on morphology. The analyses provided a clear morphometric separation of the aphids originating from Compositae and those collected on Cucurbitaceae and Malvaceae, regardless of the geographical origin of the aphids and the host plant on which they were reared. This indicates that within A. gossypii there are two widely distributed host races or subspecies with different plant family associations. The taxonomic implications are discussed

The effects of education on agricultural productivity under traditional and improved technology in northern Nigeria: an endogenous switching regression analysis

Cowpea, Schooling, Extension, Technology adoption, Nigeria,