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Journal and Journal Articles: Recent submissions
Now showing items 2161-2180 of 5277
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Cassava: from poor farmers crop to pacesetter of African rural development
(2003)Cassava(Manihot esculenta), a root crop originating in Tropical America, has been called Africa’s food insurance but vital as that is, it has the potential to be much more. Already, cassava provides more than half of the dietary calories for over 200 million people in sub-Saharan Africa (about half of the total population). It also contributes substantial amounts of protein, minerals (iron and calcium) and vitamins (A and C) through leaf consumption (Table 1) though to a much smaller population ... -
Biotechnology, the gene revolution, and proprietary technology in agriculture: a strategic note for the World Bank
(2001)The world economy experienced significant growth and transformation, with increases in productivity, product quality, and export base diversification in the 1990s. These advances were mainly driven by the growth of traditional agricultural and industrial sectors, including the natural resource-based sectors. This article outlines how application that New Science offers an opportunity for equitable growth that will assist in further poverty alleviation throughout the world. New Science will impact ... -
Longterm soil organic carbon dynamics in a subhumid tropical climate: 13C data in mixed C3/C4 cropping and modeling with ROTHC
(2004)Scanty information on long-term soil organic carbon (SOC) dynamics hampers validation of SOC models in the tropics. We observed SOC content changes in a 16-year continuously cropped agroforestry experiment in Ibadan, south-western Nigeria. SOC levels declined in all treatments. The decline was most pronounced in the no-tree control treatments with continuous maize and cowpea cropping, where SOC levels dropped from the initial 15.4 to 7.3–8.0 Mg C ha−1 in the 0–12 cm topsoil in 16 years. In the two ... -
Replenishment of C, N, and P in a degraded alfisol under humid tropical conditions; effect of fallow species and litter polyphenols
(2001-09)The capacity of vegetation fallow to replenish carbon and nutrients in degraded soil is related largely to the nature of the fallow vegetation, particularly the chemical composition. Therefore, a study was conducted at Ibadan, southwestern Nigeria (humid tropics), to look into these relationships using fallow species with varying chemical compositions. The treatments include three woody species, Senna siamea, Acacia leptocarpa and Leucaena leucocephala, planted in 1989, and the natural shrub ... -
Assessment of phenotypic variation of winter barley in Scandinavia
(2001)Phenotypic diversity for agronomic characteristics was determined in an experiment without fertilizer in 1998 in 41 two-row and 21 six-row winter barley accessions, provided by the Nordic Gene Bank, at Højbakkegård (Denmark). There were significant differences among these 62 accessions for spring establishment, early flowering, covering, plant height, lodging, tillering, spike length, number of kernels per spike and thousand kernel weight. On average, two-row barley accessions had better establishment, ... -
First report of aflatoxin in dried yam chips in Benin
(2001-09)Dried yam (Dioscorea spp.) chips are widely consumed in Bénin but are often attacked by molds. Invasion of food by Aspergillus flavus may lead to aflatoxin contamination. We report here the result of a survey on the sanitary quality of dried yam chips in Bénin. During July and August 2000, 50 dried yam chips samples were collected from different points in the marketing chain; 10 samples were collected from each of 5 stages: producers, wholesalers, retailers, dried yam-based food sellers and ... -
Occurrence and distribution of cowpea damping-off and stem rot and associated fungi in Benin
(2004-10)Damping-off and stem rot of cowpea is an important soil-borne disease worldwide. Cowpea fields were randomly chosen in each agro-ecological zone in Benin and surveyed in 2001 and 2002 to determine the occurrence of the diseases throughout the country. Diseased plants, prevailing environmental conditions and cowpea grower cultural practices were recorded and causal agents associated with the disease identified. Results indicated that damping-off and stem rot were distributed throughout Benin. The ... -
Effect of texture modifiers on the physicochemical and sensory properties of dried fufu
(2005-10-01)Glycerol monostearate (GMS) and monoglyceride phosphate (MGP) were added to fufu flour at different levels (0.5%, 1.0% and 1.5%) in hydrated and powdered form. There were evaluated the effects of those additives on physicochemical and sensory properties of dried fufu. Addition of GMS and MGP had a significant effect on the swelling power, solubility, pasting properties and sensory quality of fufu flour. Results obtained were: Dispersibility (69%-70.33%), water absorption index (WAI, 47.7%-54.4%), ... -
Technology adoption and farmer efficiency in multiple crops production in eastern Ethiopia: a comparison of parametric and non-parametric distance functions
(2005-02)(PDF) and data envelopment analysis (DEA) with applications to adopters of improved cereal production technology in eastern Ethiopia. The results from both approaches revealed substantial technical inefficiencies of production among the sample farmers. Technical efficiency estimates obtained from the two approaches are positively and significantly correlated. However, the DEA approach is shown to be very sensitive to outliers as well as to the choice of orientation. The PDF results are relatively ... -
Evaluation of the suitability of cassava and sweetpotato flours for pasta production
(2005)The study was carried out to establish the proportions of cassava and sweetpotato flours that would produce good quality pasta, in composite with wheat flour. Up to 50% sweetpotato and cassava flour substitutions were made. Two varieties each of cassava (Abasafitaa and Afisiafi) and sweetpotato (Faara and Sauti) were used. The following parameters were investigated on the flours: starch yield, moisture, ash, fibre, protein, amylose content, water binding capacity, swelling power, solubility, ... -
Control of Helicotylenchus multicinctus and Meloidogyne javanica in established plantain and nematode survival as influenced by rainfall: Combate de helicotylenchus multicinctus y meloidogyne javanica en platano y el efecto de la lluvia sobre la supervivencia de nematodos
(1980-04)Soil treatment with oxamyl and carbofuran at 3 g followed by 1.2 g a.i./plant after 4 months reduced damage caused by Helicotylenchus multicinctus and Meloidogyne javanica to established plantain (Musa AAB). Treatment appreciably reduced nematode populations and significantly increased vigor and yield of plantain. Oxamyl gave the best response followed by carbofuran increasing yields by 98 and 61% respectively. One liquid formulation of oxamyl applied to foliage gave less nematode control and less ... -
The employment of a nonfumigant nematicide for control of the root-knot and lesion nematodes on yams and crop preservation in storage: Uso de un nematicida no fumigante para combatir los nematodos noduladores y lesionadores en name y para la preservacion de la cosecha en almacenaje
(1980-10)The nematicidal efficacy of oxamyl as a non-fumigant nematicide in controlling damage caused by the root-knot nematode (Meloidogyne javanica) and the lesion nematode (Pratylenchus brachyurus) to the white yam (Dioscorea rotundata) was investigated under field and storage conditions. Infection of yams by these nematodes in the field affects the survival of tubers in storage and threatens the maintenance of yams as vegetatively propagated clones. Populations of M. javanica and P. brachyurus in the ... -
Alley cropping in the moist savanna of West Africa II. Impact on soil productivity in a northtosouth transect in Togo
(1999)The moist savanna of West-Africa is characterized by a wide range of climates and soil types. The impact of the biophysical environment on hedgerow N uptake, wood production and maize grain yield was assessed for three years in three alley cropping trials with a selected number of hedgerow species in Glidji (Southern Togo), Amoutchou (Central Togo), and Sarakawa (Northern Togo). Senna siamea hedgerows accumulated significantly more N in the first pruning in Glidji (129−138 kg N ha−1) and Sarakawa ... -
An assessment of the impact of biological and chemical grasshopper control agents on grounddwelling arthropods in Niger, based on presence/absence sampling
(1999)Medium-scale experimental field applications of two grasshopper and locust control agents, the mycoinsecticide Metarhizium anisopliae (flavoviride) var. acridum (Deuteromycotina: Hyphomycetes) and the organophosphate fenitrothion, were carried out in August 1996 in Maı̈ne Soroa, Niger. The objective was to evaluate effects and side-effects on target grasshoppers and epigeal non-target arthropods, using simple binary (presence/absence) sampling techniques. Plots (≈50 ha, 3 replicates) were treated ... -
Reaction of cowpea (Vigna unguiculata L. Walp.) to six isolates of blackeye cowpea mosaic virus (BlCMV) and cowpea aphidborne mosaic virus (CAMV), two potyviruses infecting cowpea in Nigeria
(1998)Five potyvirus isolates from various cowpea-producing areas (Guinea and Sudan savannas and forest zones) in Nigeria were identified by serology and infectivity tests as BlCMV (Isolates IT15, IT16 and WC) or as CAMV (isolates IT11 and ZARIA) and compared with the standard isolate of blackeye cowpea mosaic virus (BlCMV) (isolate ONNE) used at the International Institute of Tropical Agriculture (IITA) for screening purposes. According to the type and severity of symptoms on Nicotiana benthamiana and ... -
Farmers' adoptability of Mucuna fallowing and agroforestry technologies in the coastal savanna of Benin
(1998)As technologies to counter soil fertility decline, alley farming with Leucaena leucocephala and Gliricidia sepium, annual short-season Mucuna pruriëns var. Utilis fallowing, and perennial Acacia auriculiformis fallowing have been tested. With alley farming, timely pruning is a critical element in farmers' capacity to match on-station yield levels: 55% of the farmers who delayed pruning suffered about 60% yield losses. Farmers are now comparing a new alley band concept, grouping trees in bands 20 ... -
Exploitation of a woody host plant and cerambycidassociated volatiles as hostfinding cues by the larger grain borer (Coleoptera: Bostrichidae)
(1998)We collected twigs of Lannea nigritiana (Sc. Elliot) Keay attacked by the girdling cerambycid Analeptes trifasciata F. in the Lama forest of central Benin, West Africa. Emergence data from A. trifasciata wood samples revealed a diverse insect fauna, which consisted of 27 primarily coleopteran species of 8 different families. More than 70% of the identified insects were bostrichids. We report an association of the exotic larger grain borer, Pmstephanits tnmcatiis (Horn), and its introduced natural ... -
Decentralised onfarm seed potato production from prebasic minitubers: a case study from Nepal
(1998)The on-farm performance of more than 150 000 pre-basic potato (Solanum tuberosum) minitubers of 1–10 g was monitored over two years in contrasting environments in Nepal. Average minituber productivity (grams of basic seed produced per minituber planted) was 171 g in the southern plains and 116 g in the hills. Although the performance of minitubers varied between environments, minituber sizes and potato varieties, the overall results clearly indicated that minitubers can be successfully multiplied ... -
Soil macroaggregate stability under different fallow management systems and cropping intensities in southwestern Nigeria
(1999)Evaluation of soil aggregate stability under managed fallow systems is very relevant in the assessment of their agricultural sustainability. It is also important to identify the parameters that are most responsive to the effects of these fallow systems on aggregate stability. This study was carried out in southwestern Nigeria to quantify the effects of various fallow management systems on the macroaggregate stability of surface soil (0–15-cm depth) using a long-term fallow management trial established ...
